Start an image tool

This is meant to provide a convenient way to produce images in
specific color states and memory formats.

gdk/gdk.h

@@ -30,6 +30,7 @@
 #include <gdk/gdkcairo.h>
 #include <gdk/gdkcairocontext.h>
 #include <gdk/gdkclipboard.h>
+#include <gdk/gdkcolorstate.h>
 #include <gdk/gdkconfig.h>
 #include <gdk/gdkcontentdeserializer.h>
 #include <gdk/gdkcontentformats.h>

gdk/gdkcolorstate.c

@@ -0,0 +1,355 @@
+/* gdkcolorstate.c
+ *
+ * Copyright 2024 Matthias Clasen
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gdkcolorstateprivate.h"
+
+#include <glib/gi18n-lib.h>
+
+/**
+ * GdkColorState:
+ *
+ * A `GdkColorState` object provides the information to interpret
+ * colors and pixels in a variety of ways.
+ *
+ * They are also known as
+ * [*color spaces*](https://en.wikipedia.org/wiki/Color_space).
+ *
+ * Crucially, GTK knows how to convert colors from one color
+ * state to another.
+ *
+ * `GdkColorState objects are immutable and therefore threadsafe.
+ *
+ * Since 4.16
+ */
+
+G_DEFINE_BOXED_TYPE (GdkColorState, gdk_color_state,
+                     gdk_color_state_ref, gdk_color_state_unref);
+
+/* {{{ Public API */
+
+/**
+ * gdk_color_state_ref:
+ * @self: a `GdkColorState`
+ *
+ * Increase the reference count of @self.
+ *
+ * Returns: the object that was passed in
+ * 
+ * Since: 4.16
+ */
+GdkColorState *
+(gdk_color_state_ref) (GdkColorState *self)
+{
+  return _gdk_color_state_ref (self);
+}
+
+/**
+ * gdk_color_state_unref:
+ * @self:a `GdkColorState`
+ *
+ * Decrease the reference count of @self.
+ *
+ * Unless @self is static, it will be freed
+ * when the reference count reaches zero.
+ *
+ * Since: 4.16
+ */
+void
+(gdk_color_state_unref) (GdkColorState *self)
+{
+  _gdk_color_state_unref (self);
+}
+
+/**
+ * gdk_color_state_get_srgb:
+ *
+ * Returns the color state object representing the sRGB color space.
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_color_state_get_srgb (void)
+{
+  return GDK_COLOR_STATE_SRGB;
+}
+
+/**
+ * gdk_color_state_get_srgb_linear:
+ *
+ * Returns the color state object representing the linearized sRGB color space.
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_color_state_get_srgb_linear (void)
+{
+  return GDK_COLOR_STATE_SRGB_LINEAR;
+}
+
+/**
+ * gdk_color_state_equal:
+ * @self: a `GdkColorState`
+ * @other: another `GdkColorStatee`
+ *
+ * Compares two `GdkColorStates` for equality.
+ *
+ * Note that this function is not guaranteed to be perfect and two objects
+ * describing the same color state may compare not equal. However, different
+ * color states will never compare equal.
+ *
+ * Returns: %TRUE if the two color states compare equal
+ *
+ * Since: 4.16
+ */
+gboolean
+(gdk_color_state_equal) (GdkColorState *self,
+                         GdkColorState *other)
+{
+  return _gdk_color_state_equal (self, other);
+}
+
+/*< private >
+ * gdk_color_state_new_from_icc_profile:
+ * @icc_profile: The ICC profiles given as a `GBytes`
+ * @error: Return location for an error
+ *
+ * Creates a new color state for the given ICC profile data.
+ *
+ * If the given ICC profile can not be represented as a
+ * [struct@Gdk.ColorState], `NULL` is returned and an error
+ * is raised.
+ *
+ * Returns: a new `GdkColorState` or %NULL on error
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_color_state_new_from_icc_profile (GBytes  *icc_profile,
+                                      GError **error)
+{
+  GBytes *bytes;
+
+  g_return_val_if_fail (icc_profile != NULL, NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+  bytes = g_resources_lookup_data ("/org/gtk/libgdk/icc/srgb.icc", 0, NULL);
+  if (g_bytes_equal (icc_profile, bytes))
+    {
+      g_bytes_unref (bytes);
+      return GDK_COLOR_STATE_SRGB;
+    }
+
+  bytes = g_resources_lookup_data ("/org/gtk/libgdk/icc/srgb-linear.icc", 0, NULL);
+  if (g_bytes_equal (icc_profile, bytes))
+    {
+      g_bytes_unref (bytes);
+      return GDK_COLOR_STATE_SRGB_LINEAR;
+    }
+
+  g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                       _("Failed to load ICC profile"));
+  return NULL;
+}
+
+/*< private >
+ * gdk_color_state_new_from_cicp_data:
+ * @color_primaries: the color primaries
+ * @transfer_characteristics: the transfer function
+ * @matrix_coefficients: the color matrix
+ * @full_range: whether the data is 'full-range'
+ * @error: Return location for an error
+ *
+ * Creates a new color state for the given CICP data.
+ *
+ * If the given CICP data can not be represented as a
+ * [struct@Gdk.ColorState], `NULL` is returned and an error
+ * is raised.
+ *
+ * See [CICP](https://en.wikipedia.org/wiki/Coding-independent_code_points)
+ * for more information about CICP.
+ *
+ * Returns: a new `GdkColorState` or %NULL on error
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_color_state_new_from_cicp_data (int      color_primaries,
+                                    int      transfer_characteristics,
+                                    int      matrix_coefficients,
+                                    gboolean full_range)
+{
+  if (color_primaries == 0 && transfer_characteristics == 13 &&
+      matrix_coefficients == 0 && full_range)
+    return GDK_COLOR_STATE_SRGB;
+  else if (color_primaries == 0 && transfer_characteristics == 8 &&
+           matrix_coefficients == 0 && full_range)
+    return GDK_COLOR_STATE_SRGB_LINEAR;
+
+  return NULL;
+}
+
+/*< private >
+ * gdk_color_state_save_to_icc_profile:
+ * @self: a `GdkColorState`
+ * @error: Return location for an error
+ *
+ * Saves the color state to an
+ * [ICC profile](https://en.wikipedia.org/wiki/ICC_profile).
+ *
+ * It may not be possible to represent a color state as ICC profile.
+ * In that case, @error will be set and %NULL will be returned.
+ *
+ * Returns: (nullable): A new `GBytes` containing the ICC profile
+ *
+ * Since: 4.16
+ */
+GBytes *
+gdk_color_state_save_to_icc_profile (GdkColorState  *self,
+                                     GError        **error)
+{
+  GBytes *bytes;
+
+  if (self == GDK_COLOR_STATE_SRGB)
+    {
+      bytes = g_resources_lookup_data ("/org/gtk/libgdk/icc/srgb.icc", 0, NULL);
+      g_assert (bytes != NULL);
+    }
+  else if (self == GDK_COLOR_STATE_SRGB_LINEAR)
+    {
+      bytes = g_resources_lookup_data ("/org/gtk/libgdk/icc/srgb-linear.icc", 0, NULL);
+      g_assert (bytes != NULL);
+    }
+  else
+    {
+      bytes = NULL;
+      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                           _("ICC profile not supported for this color state"));
+    }
+
+  return bytes;
+}
+
+/*< private >
+ * gdk_color_state_save_to_cicp_data:
+ * @self: a `GdkColorState`
+ * @color_primaries: return location for color primaries
+ * @transfer_characteristics: return location for transfer characteristics
+ * @matrix_coefficients: return location for matrix_coefficients
+ * @full_range: return location for the full range flag
+ * @error: Return location for an error
+ *
+ * Saves the color state as CICP data.
+ *
+ * It may not be possible to represent a color state as CICP data.
+ * In that case, @error will be set and `FALSE` will be returned.
+ *
+ * See [CICP](https://en.wikipedia.org/wiki/Coding-independent_code_points)
+ * for more information about CICP.
+ *
+ * Returns: (nullable): `TRUE` if the out arguments were set
+ *
+ * Since: 4.16
+ */
+gboolean
+gdk_color_state_save_to_cicp_data (GdkColorState  *self,
+                                   int            *color_primaries,
+                                   int            *transfer_characteristics,
+                                   int            *matrix_coefficients,
+                                   gboolean       *full_range,
+                                   GError        **error)
+{
+  if (self == GDK_COLOR_STATE_SRGB)
+    {
+      *color_primaries = 0;
+      *transfer_characteristics = 13;
+      *matrix_coefficients = 0;
+      *full_range = TRUE;
+      return TRUE;
+    }
+  else if (self == GDK_COLOR_STATE_SRGB_LINEAR)
+    {
+      *color_primaries = 0;
+      *transfer_characteristics = 8;
+      *matrix_coefficients = 0;
+      *full_range = TRUE;
+      return TRUE;
+    }
+
+  g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
+                       _("This color state does not support CICP data"));
+  return FALSE;
+}
+
+/* }}} */
+/* {{{ Default implementation */
+
+const char *
+gdk_color_state_get_name_from_id (GdkColorStateId id)
+{
+  const char *names[] = {
+    "srgb", "srgb-linear",
+  };
+
+  return names[id];
+}
+
+GdkColorState gdk_default_color_states[] = {
+  { NULL, 0 },
+  { NULL, 0 },
+};
+
+/* }}} */
+/* {{{ Private API */
+
+const char *
+gdk_color_state_get_name (GdkColorState *self)
+{
+  if (GDK_IS_DEFAULT_COLOR_STATE (self))
+    {
+      switch (GDK_DEFAULT_COLOR_STATE_ID (self))
+        {
+        case GDK_COLOR_STATE_ID_SRGB: return "srgb";
+        case GDK_COLOR_STATE_ID_SRGB_LINEAR: return "srgb-linear";
+        default: g_assert_not_reached ();
+        }
+    }
+
+  return self->klass->get_name (self);
+}
+
+void
+gdk_color_state_print (GdkColorState *self,
+                       GString       *string)
+{
+  g_string_append (string, gdk_color_state_get_name (self));
+}
+
+GdkMemoryDepth
+gdk_color_state_get_min_depth (GdkColorState *self)
+{
+  if (self == GDK_COLOR_STATE_SRGB || self == GDK_COLOR_STATE_SRGB_LINEAR)
+    return GDK_MEMORY_U8;
+
+  return GDK_MEMORY_FLOAT16;
+}
+
+/* }}} */
+
+/* vim:set foldmethod=marker expandtab: */

gdk/gdkcolorstate.h

@@ -0,0 +1,50 @@
+/* gdkcolorstate.h
+ *
+ * Copyright 2024 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#if !defined (__GDK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gdk/gdk.h> can be included directly."
+#endif
+
+#include <gdk/gdktypes.h>
+
+G_BEGIN_DECLS
+
+#define GDK_TYPE_COLOR_STATE (gdk_color_state_get_type ())
+
+GDK_AVAILABLE_IN_4_16
+GType           gdk_color_state_get_type                (void) G_GNUC_CONST;
+
+GDK_AVAILABLE_IN_4_16
+GdkColorState * gdk_color_state_ref                     (GdkColorState  *self);
+
+GDK_AVAILABLE_IN_4_16
+void            gdk_color_state_unref                   (GdkColorState  *self);
+
+GDK_AVAILABLE_IN_4_16
+GdkColorState * gdk_color_state_get_srgb                (void);
+
+GDK_AVAILABLE_IN_4_16
+GdkColorState * gdk_color_state_get_srgb_linear         (void);
+
+GDK_AVAILABLE_IN_4_16
+gboolean        gdk_color_state_equal                   (GdkColorState  *self,
+                                                         GdkColorState  *other);
+
+G_END_DECLS

gdk/gdkcolorstateprivate.h

@@ -0,0 +1,102 @@
+#pragma once
+
+#include "gdkcolorstate.h"
+#include "gdkmemoryformatprivate.h"
+
+typedef enum
+{
+  GDK_COLOR_STATE_ID_SRGB,
+  GDK_COLOR_STATE_ID_SRGB_LINEAR,
+} GdkColorStateId;
+
+typedef struct _GdkColorStateClass GdkColorStateClass;
+
+struct _GdkColorState
+{
+  GdkColorStateClass *klass;
+  int ref_count;
+};
+
+struct _GdkColorStateClass
+{
+  void                  (* free)                (GdkColorState  *self);
+  gboolean              (* equal)               (GdkColorState  *self,
+                                                 GdkColorState  *other);
+  const char *          (* get_name)            (GdkColorState  *self);
+};
+
+extern GdkColorState gdk_default_color_states[];
+
+#define GDK_COLOR_STATE_SRGB        (&gdk_default_color_states[GDK_COLOR_STATE_ID_SRGB])
+#define GDK_COLOR_STATE_SRGB_LINEAR (&gdk_default_color_states[GDK_COLOR_STATE_ID_SRGB_LINEAR])
+
+#define GDK_IS_DEFAULT_COLOR_STATE(c) (GDK_COLOR_STATE_SRGB <= (c) && (c) <= GDK_COLOR_STATE_SRGB_LINEAR)
+#define GDK_DEFAULT_COLOR_STATE_ID(c) ((GdkColorStateId) (c - gdk_default_color_states))
+
+const char *    gdk_color_state_get_name                (GdkColorState          *color_state);
+const char *    gdk_color_state_get_name_from_id        (GdkColorStateId         id);
+void            gdk_color_state_print                   (GdkColorState          *color_state,
+                                                         GString                *string);
+
+GdkMemoryDepth  gdk_color_state_get_min_depth           (GdkColorState          *color_state);
+
+#define gdk_color_state_ref(self) _gdk_color_state_ref (self)
+static inline GdkColorState *
+_gdk_color_state_ref (GdkColorState *self)
+{
+  if (GDK_IS_DEFAULT_COLOR_STATE (self))
+    return self;
+
+  self->ref_count++;
+
+  return self;
+}
+
+#define gdk_color_state_unref(self) _gdk_color_state_unref (self)
+static inline void
+_gdk_color_state_unref (GdkColorState *self)
+{
+  if (GDK_IS_DEFAULT_COLOR_STATE (self))
+    return;
+
+  self->ref_count--;
+
+  if (self->ref_count == 0)
+    self->klass->free (self);
+}
+
+#define gdk_color_state_equal(a,b) _gdk_color_state_equal ((a), (b))
+static inline gboolean
+_gdk_color_state_equal (GdkColorState *self,
+                        GdkColorState *other)
+{
+  if (self == other)
+    return TRUE;
+
+  if (GDK_IS_DEFAULT_COLOR_STATE (self) || GDK_IS_DEFAULT_COLOR_STATE (other))
+    return FALSE;
+
+  if (self->klass != other->klass)
+    return FALSE;
+
+  return self->klass->equal (self, other);
+}
+
+GdkColorState * gdk_color_state_new_from_icc_profile    (GBytes         *icc_profile,
+                                                         GError        **error);
+
+GdkColorState * gdk_color_state_new_from_cicp_data      (int             color_primaries,
+                                                         int             transfer_characteristics,
+                                                         int             matrix_coefficients,
+                                                         gboolean        full_range);
+
+GBytes *        gdk_color_state_save_to_icc_profile     (GdkColorState  *self,
+                                                         GError        **error);
+
+gboolean        gdk_color_state_save_to_cicp_data       (GdkColorState  *self,
+                                                         int            *color_primaries,
+                                                         int            *transfer_characteristic,
+                                                         int            *matrix_coefficients,
+                                                         gboolean       *full_range,
+                                                         GError        **error);
+

gdk/gdkdisplay.c

@@ -1874,6 +1874,8 @@ gdk_display_init_egl (GdkDisplay  *self,
     epoxy_has_egl_extension (priv->egl_display, "EGL_EXT_image_dma_buf_import_modifiers");
   self->have_egl_dma_buf_export =
     epoxy_has_egl_extension (priv->egl_display, "EGL_MESA_image_dma_buf_export");
+  self->have_egl_gl_colorspace =
+    epoxy_has_egl_extension (priv->egl_display, "EGL_KHR_gl_colorspace");
 
   if (self->have_egl_no_config_context)
     priv->egl_config_high_depth = gdk_display_create_egl_config (self,

gdk/gdkdisplayprivate.h

@@ -130,6 +130,7 @@ struct _GdkDisplay
   guint have_egl_pixel_format_float : 1;
   guint have_egl_dma_buf_import : 1;
   guint have_egl_dma_buf_export : 1;
+  guint have_egl_gl_colorspace : 1;
 
   GdkDmabufFormats *dmabuf_formats;
   GdkDmabufDownloader *dmabuf_downloaders[4];

gdk/gdkdmabuftexture.c

@@ -200,6 +200,7 @@ gdk_dmabuf_texture_new_from_builder (GdkDmabufTextureBuilder *builder,
   self = g_object_new (GDK_TYPE_DMABUF_TEXTURE,
                        "width", width,
                        "height", height,
+                       "color-state", gdk_dmabuf_texture_builder_get_color_state (builder),
                        NULL);
 
   g_set_object (&self->display, display);

gdk/gdkdmabuftexturebuilder.c

@@ -24,6 +24,7 @@
 #include "gdkdebugprivate.h"
 #include "gdkdisplay.h"
 #include "gdkenumtypes.h"
+#include "gdkcolorstate.h"
 #include "gdkdmabuftextureprivate.h"
 #include "gdkdmabuftexturebuilderprivate.h"
 
@@ -41,6 +42,8 @@ struct _GdkDmabufTextureBuilder
 
   GdkDmabuf dmabuf;
 
+  GdkColorState *color_state;
+
   GdkTexture *update_texture;
   cairo_region_t *update_region;
 };
@@ -124,6 +127,7 @@ enum
   PROP_MODIFIER,
   PROP_PREMULTIPLIED,
   PROP_N_PLANES,
+  PROP_COLOR_STATE,
   PROP_UPDATE_REGION,
   PROP_UPDATE_TEXTURE,
 
@@ -141,6 +145,7 @@ gdk_dmabuf_texture_builder_dispose (GObject *object)
 
   g_clear_object (&self->update_texture);
   g_clear_pointer (&self->update_region, cairo_region_destroy);
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
 
   G_OBJECT_CLASS (gdk_dmabuf_texture_builder_parent_class)->dispose (object);
 }
@@ -183,6 +188,10 @@ gdk_dmabuf_texture_builder_get_property (GObject    *object,
       g_value_set_uint (value, self->dmabuf.n_planes);
       break;
 
+    case PROP_COLOR_STATE:
+      g_value_set_boxed (value, self->color_state);
+      break;
+
     case PROP_UPDATE_REGION:
       g_value_set_boxed (value, self->update_region);
       break;
@@ -235,6 +244,10 @@ gdk_dmabuf_texture_builder_set_property (GObject      *object,
       gdk_dmabuf_texture_builder_set_n_planes (self, g_value_get_uint (value));
       break;
 
+    case PROP_COLOR_STATE:
+      gdk_dmabuf_texture_builder_set_color_state (self, g_value_get_boxed (value));
+      break;
+
     case PROP_UPDATE_REGION:
       gdk_dmabuf_texture_builder_set_update_region (self, g_value_get_boxed (value));
       break;
@@ -347,6 +360,18 @@ gdk_dmabuf_texture_builder_class_init (GdkDmabufTextureBuilderClass *klass)
                        1, GDK_DMABUF_MAX_PLANES, 1,
                        G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
 
+  /**
+   * GdkDmabufTextureBuilder:color-state: (attributes org.gtk.Property.get=gdk_dmabuf_texture_builder_get_color_state org.gtk.Property.set=gdk_dmabuf_texture_builder_set_color_state)
+   *
+   * The color state of the texture.
+   *
+   * Since: 4.16
+   */
+  properties[PROP_COLOR_STATE] =
+    g_param_spec_boxed ("color-state", NULL, NULL,
+                        GDK_TYPE_COLOR_STATE,
+                        G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
   /**
    * GdkDmabufTextureBuilder:update-region: (attributes org.gtk.Property.get=gdk_dmabuf_texture_builder_get_update_region org.gtk.Property.set=gdk_dmabuf_texture_builder_set_update_region)
    *
@@ -383,6 +408,8 @@ gdk_dmabuf_texture_builder_init (GdkDmabufTextureBuilder *self)
 
   for (int i = 0; i < GDK_DMABUF_MAX_PLANES; i++)
     self->dmabuf.planes[i].fd = -1;
+
+  self->color_state = gdk_color_state_get_srgb ();
 }
 
 /**
@@ -843,6 +870,48 @@ gdk_dmabuf_texture_builder_set_offset (GdkDmabufTextureBuilder *self,
   self->dmabuf.planes[plane].offset = offset;
 }
 
+/**
+ * gdk_dmabuf_texture_builder_get_color_state: (attributes org.gtk.Method.get_property=color-state)
+ * @self: a `GdkDmabufTextureBuilder`
+ *
+ * Gets the color state previously set via gdk_dmabuf_texture_builder_set_color_state().
+ *
+ * Returns: the color state
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_dmabuf_texture_builder_get_color_state (GdkDmabufTextureBuilder *self)
+{
+  g_return_val_if_fail (GDK_IS_DMABUF_TEXTURE_BUILDER (self), NULL);
+
+  return self->color_state;
+}
+
+/**
+ * gdk_dmabuf_texture_builder_set_color_state: (attributes org.gtk.Method.set_property=color-state)
+ * @self: a `GdkDmabufTextureBuilder`
+ * @color_state: a `GdkColorState`
+ *
+ * Sets the color state for the texture. The default is SRGB.
+ *
+ * Since: 4.16
+ */
+void
+gdk_dmabuf_texture_builder_set_color_state (GdkDmabufTextureBuilder *self,
+                                            GdkColorState           *color_state)
+{
+  g_return_if_fail (GDK_IS_DMABUF_TEXTURE_BUILDER (self));
+  g_return_if_fail (color_state != NULL);
+
+  if (self->color_state != color_state)
+    {
+      g_clear_pointer (&self->color_state, gdk_color_state_unref);
+      self->color_state = gdk_color_state_ref (color_state);
+      g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_COLOR_STATE]);
+    }
+}
+
 /**
  * gdk_dmabuf_texture_builder_get_update_texture: (attributes org.gtk.Method.get_property=update-texture)
  * @self: a `GdkDmabufTextureBuilder`

gdk/gdkdmabuftexturebuilder.h

@@ -100,6 +100,12 @@ void                     gdk_dmabuf_texture_builder_set_offset       (GdkDmabufT
                                                                       unsigned int                plane,
                                                                       unsigned int                offset);
 
+GDK_AVAILABLE_IN_4_16
+GdkColorState *          gdk_dmabuf_texture_builder_get_color_state    (GdkDmabufTextureBuilder  *self);
+GDK_AVAILABLE_IN_4_16
+void                     gdk_dmabuf_texture_builder_set_color_state    (GdkDmabufTextureBuilder  *self,
+                                                                        GdkColorState            *color_state);
+
 GDK_AVAILABLE_IN_4_14
 GdkTexture *             gdk_dmabuf_texture_builder_get_update_texture (GdkDmabufTextureBuilder  *self) G_GNUC_PURE;
 GDK_AVAILABLE_IN_4_14

gdk/gdkglcontext.c

@@ -1758,6 +1758,8 @@ gdk_gl_context_check_extensions (GdkGLContext *context)
 
   priv->features = supported_features & ~disabled_features;
 
+  glEnable (GL_FRAMEBUFFER_SRGB);
+
   gdk_gl_context_init_memory_flags (context);
 
   if ((priv->features & GDK_GL_FEATURE_DEBUG) && gl_debug)

gdk/gdkgltexture.c

@@ -151,7 +151,7 @@ gdk_gl_texture_find_format (GdkGLContext    *context,
 
   for (format = 0; format < GDK_MEMORY_N_FORMATS; format++)
     {
-      GLint q_internal_format;
+      GLint q_internal_format, q_internal_srgb_format;
       GLenum q_format, q_type;
       GLint q_swizzle[4];
 
@@ -164,6 +164,7 @@ gdk_gl_texture_find_format (GdkGLContext    *context,
       gdk_memory_format_gl_format (format,
                                    gdk_gl_context_get_use_es (context),
                                    &q_internal_format,
+                                   &q_internal_srgb_format,
                                    &q_format,
                                    &q_type,
                                    q_swizzle);
@@ -187,7 +188,7 @@ gdk_gl_texture_do_download (GdkGLTexture *self,
   GdkMemoryFormat format;
   gsize expected_stride;
   Download *download = download_;
-  GLint gl_internal_format;
+  GLint gl_internal_format, gl_internal_srgb_format;
   GLenum gl_format, gl_type;
   GLint gl_swizzle[4];
 
@@ -199,7 +200,7 @@ gdk_gl_texture_do_download (GdkGLTexture *self,
     {
       gdk_memory_format_gl_format (format,
                                    gdk_gl_context_get_use_es (context),
-                                   &gl_internal_format,
+                                   &gl_internal_format, &gl_internal_srgb_format,
                                    &gl_format, &gl_type, gl_swizzle);
       if (download->stride == expected_stride &&
           download->format == format)
@@ -262,7 +263,7 @@ gdk_gl_texture_do_download (GdkGLTexture *self,
 
               gdk_memory_format_gl_format (actual_format,
                                            gdk_gl_context_get_use_es (context),
-                                           &gl_internal_format,
+                                           &gl_internal_format, &gl_internal_srgb_format,
                                            &gl_read_format, &gl_read_type, gl_swizzle);
             }
         }
@@ -274,7 +275,7 @@ gdk_gl_texture_do_download (GdkGLTexture *self,
 
           gdk_memory_format_gl_format (actual_format,
                                        gdk_gl_context_get_use_es (context),
-                                       &gl_internal_format,
+                                       &gl_internal_format, &gl_internal_srgb_format,
                                        &gl_read_format, &gl_read_type, gl_swizzle);
         }
 
@@ -487,6 +488,7 @@ gdk_gl_texture_new_from_builder (GdkGLTextureBuilder *builder,
   self = g_object_new (GDK_TYPE_GL_TEXTURE,
                        "width", gdk_gl_texture_builder_get_width (builder),
                        "height", gdk_gl_texture_builder_get_height (builder),
+                       "color-state", gdk_gl_texture_builder_get_color_state (builder),
                        NULL);
 
   self->context = g_object_ref (gdk_gl_texture_builder_get_context (builder));

gdk/gdkgltexturebuilder.c

@@ -23,6 +23,7 @@
 
 #include "gdkenumtypes.h"
 #include "gdkglcontext.h"
+#include "gdkcolorstate.h"
 #include "gdkgltextureprivate.h"
 
 #include <cairo-gobject.h>
@@ -38,6 +39,7 @@ struct _GdkGLTextureBuilder
   GdkMemoryFormat format;
   gboolean has_mipmap;
   gpointer sync;
+  GdkColorState *color_state;
 
   GdkTexture *update_texture;
   cairo_region_t *update_region;
@@ -75,6 +77,7 @@ enum
   PROP_HEIGHT,
   PROP_ID,
   PROP_SYNC,
+  PROP_COLOR_STATE,
   PROP_UPDATE_REGION,
   PROP_UPDATE_TEXTURE,
   PROP_WIDTH,
@@ -95,6 +98,7 @@ gdk_gl_texture_builder_dispose (GObject *object)
 
   g_clear_object (&self->update_texture);
   g_clear_pointer (&self->update_region, cairo_region_destroy);
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
 
   G_OBJECT_CLASS (gdk_gl_texture_builder_parent_class)->dispose (object);
 }
@@ -133,6 +137,10 @@ gdk_gl_texture_builder_get_property (GObject    *object,
       g_value_set_pointer (value, self->sync);
       break;
 
+    case PROP_COLOR_STATE:
+      g_value_set_object (value, self->color_state);
+      break;
+
     case PROP_UPDATE_REGION:
       g_value_set_boxed (value, self->update_region);
       break;
@@ -185,6 +193,10 @@ gdk_gl_texture_builder_set_property (GObject      *object,
       gdk_gl_texture_builder_set_sync (self, g_value_get_pointer (value));
       break;
 
+    case PROP_COLOR_STATE:
+      gdk_gl_texture_builder_set_color_state (self, g_value_get_object (value));
+      break;
+
     case PROP_UPDATE_REGION:
       gdk_gl_texture_builder_set_update_region (self, g_value_get_boxed (value));
       break;
@@ -286,6 +298,18 @@ gdk_gl_texture_builder_class_init (GdkGLTextureBuilderClass *klass)
     g_param_spec_pointer ("sync", NULL, NULL,
                           G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
 
+  /**
+   * GdkGLTextureBuilder:color-state: (attributes org.gtk.Property.get=gdk_gl_texture_builder_get_color_state org.gtk.Property.set=gdk_gl_texture_builder_set_color_state)
+   *
+   * The color state of the texture.
+   *
+   * Since: 4.16
+   */
+  properties[PROP_COLOR_STATE] =
+    g_param_spec_boxed ("color-state", NULL, NULL,
+                        GDK_TYPE_COLOR_STATE,
+                        G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
   /**
    * GdkGLTextureBuilder:update-region: (attributes org.gtk.Property.get=gdk_gl_texture_builder_get_update_region org.gtk.Property.set=gdk_gl_texture_builder_set_update_region)
    *
@@ -329,6 +353,7 @@ static void
 gdk_gl_texture_builder_init (GdkGLTextureBuilder *self)
 {
   self->format = GDK_MEMORY_R8G8B8A8_PREMULTIPLIED;
+  self->color_state = gdk_color_state_get_srgb ();
 }
 
 /**
@@ -672,6 +697,49 @@ gdk_gl_texture_builder_set_format (GdkGLTextureBuilder *self,
   g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_FORMAT]);
 }
 
+/**
+ * gdk_gl_texture_builder_get_color_state: (attributes org.gtk.Method.get_property=color-state)
+ * @self: a `GdkGLTextureBuilder`
+ *
+ * Gets the color state previously set via gdk_gl_texture_builder_set_color_state().
+ *
+ * Returns: the color state
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_gl_texture_builder_get_color_state (GdkGLTextureBuilder *self)
+{
+  g_return_val_if_fail (GDK_IS_GL_TEXTURE_BUILDER (self), NULL);
+
+  return self->color_state;
+}
+
+/**
+ * gdk_gl_texture_builder_set_color_state: (attributes org.gtk.Method.set_property=color-state)
+ * @self: a `GdkGLTextureBuilder`
+ * @color_state: a `GdkColorState`
+ *
+ * Sets the color state for the texture.
+ * Sets the color state of the texture. The default is SRGB.
+ *
+ * Since: 4.16
+ */
+void
+gdk_gl_texture_builder_set_color_state (GdkGLTextureBuilder *self,
+                                        GdkColorState       *color_state)
+{
+  g_return_if_fail (GDK_IS_GL_TEXTURE_BUILDER (self));
+  g_return_if_fail (color_state != NULL);
+
+  if (self->color_state != color_state)
+    {
+      g_clear_pointer (&self->color_state, gdk_color_state_unref);
+      self->color_state = gdk_color_state_ref (color_state);
+      g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_COLOR_STATE]);
+    }
+}
+
 /**
  * gdk_gl_texture_builder_get_update_texture: (attributes org.gtk.Method.get_property=update-texture)
  * @self: a `GdkGLTextureBuilder`

gdk/gdkgltexturebuilder.h

@@ -64,6 +64,12 @@ GDK_AVAILABLE_IN_4_12
 void                    gdk_gl_texture_builder_set_format       (GdkGLTextureBuilder    *self,
                                                                  GdkMemoryFormat         format);
 
+GDK_AVAILABLE_IN_4_16
+GdkColorState *         gdk_gl_texture_builder_get_color_state  (GdkGLTextureBuilder    *self);
+GDK_AVAILABLE_IN_4_16
+void                    gdk_gl_texture_builder_set_color_state  (GdkGLTextureBuilder    *self,
+                                                                 GdkColorState          *color_state);
+
 GDK_AVAILABLE_IN_4_12
 gboolean                gdk_gl_texture_builder_get_has_mipmap   (GdkGLTextureBuilder    *self) G_GNUC_PURE;
 GDK_AVAILABLE_IN_4_12

gdk/gdkmemoryformat.c

@@ -23,6 +23,8 @@
 
 #include "gdkdmabuffourccprivate.h"
 #include "gdkglcontextprivate.h"
+#include "gdkcolorstateprivate.h"
+#include "gtk/gtkcolorutilsprivate.h"
 
 #include "gsk/gl/fp16private.h"
 
@@ -338,7 +340,9 @@ struct _GdkMemoryFormatDescription
   struct {
     GLint internal_gl_format;
     GLint internal_gles_format;
+    GLint internal_srgb_format;
     GLenum format;
+    GLenum srgb_format;
     GLenum type;
     GLint swizzle[4];
     /* -1 if none exists, ie the format is already RGBA
@@ -348,6 +352,7 @@ struct _GdkMemoryFormatDescription
   } gl;
 #ifdef GDK_RENDERING_VULKAN
   VkFormat vk_format;
+  VkFormat vk_srgb_format;
 #endif
 #ifdef HAVE_DMABUF
   guint32 dmabuf_fourcc;
@@ -380,6 +385,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_BGRA,
+        .internal_srgb_format = -1,
         .format = GL_BGRA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -388,6 +394,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_B8G8R8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_B8G8R8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ARGB8888,
@@ -409,6 +416,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_BGRA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -417,6 +425,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_BGRA8888,
@@ -438,6 +447,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -445,6 +455,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8B8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_R8G8B8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR8888,
@@ -466,6 +477,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -474,6 +486,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_RGBA8888,
@@ -495,6 +508,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_BGRA,
+        .internal_srgb_format = -1,
         .format = GL_BGRA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -503,6 +517,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_B8G8R8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_B8G8R8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ARGB8888,
@@ -524,6 +539,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_BGRA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -532,6 +548,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_BGRA8888,
@@ -553,6 +570,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -560,6 +578,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8B8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_R8G8B8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR8888,
@@ -581,6 +600,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -589,6 +609,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_RGBA8888,
@@ -611,6 +632,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_BGRA,
+        .internal_srgb_format = -1,
         .format = GL_BGRA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ONE },
@@ -619,6 +641,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_B8G8R8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_B8G8R8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_XRGB8888,
@@ -641,6 +664,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_BGRA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ONE },
@@ -649,6 +673,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_BGRX8888,
@@ -671,6 +696,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ONE },
@@ -678,6 +704,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8B8A8_UNORM,
+    .vk_srgb_format = VK_FORMAT_R8G8B8A8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_XBGR8888,
@@ -700,6 +727,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA8,
         .internal_gles_format = GL_RGBA8,
+        .internal_srgb_format = GL_SRGB8_ALPHA8,
         .format = GL_RGBA,
         .type = GDK_GL_UNSIGNED_BYTE_FLIPPED,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ONE },
@@ -708,6 +736,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_UNDEFINED,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_RGBX8888,
@@ -730,6 +759,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGB8,
         .internal_gles_format = GL_RGB8,
+        .internal_srgb_format = GL_SRGB8,
         .format = GL_RGB,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -737,6 +767,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8B8_UNORM,
+    .vk_srgb_format = VK_FORMAT_R8G8B8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_BGR888,
@@ -759,6 +790,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGB8,
         .internal_gles_format = GL_RGB8,
+        .internal_srgb_format = GL_SRGB8,
         .format = GL_BGR,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -767,6 +799,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_B8G8R8_UNORM,
+    .vk_srgb_format = VK_FORMAT_B8G8R8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_RGB888,
@@ -792,6 +825,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGB16,
         .internal_gles_format = GL_RGB16,
+        .internal_srgb_format = -1,
         .format = GL_RGB,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -799,6 +833,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -823,6 +858,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA16,
         .internal_gles_format = GL_RGBA16,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -830,6 +866,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16A16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR16161616,
@@ -854,6 +891,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA16,
         .internal_gles_format = GL_RGBA16,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -861,6 +899,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16A16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR16161616,
@@ -885,6 +924,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGB16F,
         .internal_gles_format = GL_RGB16F,
+        .internal_srgb_format = -1,
         .format = GL_RGB,
         .type = GL_HALF_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -892,6 +932,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -915,6 +956,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA16F,
         .internal_gles_format = GL_RGBA16F,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_HALF_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -922,6 +964,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16A16_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR16161616F,
@@ -945,6 +988,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA16F,
         .internal_gles_format = GL_RGBA16F,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_HALF_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -952,6 +996,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16B16A16_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_ABGR16161616F,
@@ -976,6 +1021,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGB32F,
         .internal_gles_format = GL_RGB32F,
+        .internal_srgb_format = -1,
         .format = GL_RGB,
         .type = GL_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -983,6 +1029,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R32G32B32_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1006,6 +1053,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA32F,
         .internal_gles_format = GL_RGBA32F,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -1013,6 +1061,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R32G32B32A32_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1036,6 +1085,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RGBA32F,
         .internal_gles_format = GL_RGBA32F,
+        .internal_srgb_format = -1,
         .format = GL_RGBA,
         .type = GL_FLOAT,
         .swizzle = { GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA },
@@ -1043,6 +1093,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R32G32B32A32_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1065,6 +1116,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RG8,
         .internal_gles_format = GL_RG8,
+        .internal_srgb_format = -1,
         .format = GL_RG,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_GREEN },
@@ -1072,6 +1124,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1094,6 +1147,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RG8,
         .internal_gles_format = GL_RG8,
+        .internal_srgb_format = -1,
         .format = GL_RG,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_GREEN },
@@ -1101,6 +1155,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8G8_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1123,6 +1178,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R8,
         .internal_gles_format = GL_R8,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_ONE },
@@ -1130,6 +1186,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8_UNORM,
+    .vk_srgb_format = VK_FORMAT_R8_SRGB,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_R8,
@@ -1155,6 +1212,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RG16,
         .internal_gles_format = GL_RG16,
+        .internal_srgb_format = -1,
         .format = GL_RG,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_GREEN },
@@ -1162,6 +1220,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1187,6 +1246,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_RG16,
         .internal_gles_format = GL_RG16,
+        .internal_srgb_format = -1,
         .format = GL_RG,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_GREEN },
@@ -1194,6 +1254,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16G16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1219,6 +1280,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R16,
         .internal_gles_format = GL_R16,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_ONE },
@@ -1226,6 +1288,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = DRM_FORMAT_R16,
@@ -1248,6 +1311,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R8,
         .internal_gles_format = GL_R8,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_UNSIGNED_BYTE,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_RED },
@@ -1255,6 +1319,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R8_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1280,6 +1345,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R16,
         .internal_gles_format = GL_R16,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_UNSIGNED_SHORT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_RED },
@@ -1287,6 +1353,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16_UNORM,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1311,6 +1378,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R16F,
         .internal_gles_format = GL_R16F,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_HALF_FLOAT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_RED },
@@ -1318,6 +1386,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R16_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1342,6 +1411,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     .gl = {
         .internal_gl_format = GL_R32F,
         .internal_gles_format = GL_R32F,
+        .internal_srgb_format = -1,
         .format = GL_RED,
         .type = GL_FLOAT,
         .swizzle = { GL_RED, GL_RED, GL_RED, GL_RED },
@@ -1349,6 +1419,7 @@ static const GdkMemoryFormatDescription memory_formats[] = {
     },
 #ifdef GDK_RENDERING_VULKAN
     .vk_format = VK_FORMAT_R32_SFLOAT,
+    .vk_srgb_format = VK_FORMAT_UNDEFINED,
 #endif
 #ifdef HAVE_DMABUF
     .dmabuf_fourcc = 0,
@@ -1543,6 +1614,7 @@ void
 gdk_memory_format_gl_format (GdkMemoryFormat  format,
                              gboolean         gles,
                              GLint           *out_internal_format,
+                             GLint           *out_internal_srgb_format,
                              GLenum          *out_format,
                              GLenum          *out_type,
                              GLint            out_swizzle[4])
@@ -1551,6 +1623,7 @@ gdk_memory_format_gl_format (GdkMemoryFormat  format,
     *out_internal_format = memory_formats[format].gl.internal_gles_format;
   else
     *out_internal_format = memory_formats[format].gl.internal_gl_format;
+  *out_internal_srgb_format = memory_formats[format].gl.internal_srgb_format;
   *out_format = memory_formats[format].gl.format;
   *out_type = memory_formats[format].gl.type;
   memcpy (out_swizzle, memory_formats[format].gl.swizzle, sizeof(GLint) * 4);
@@ -1562,6 +1635,8 @@ gdk_memory_format_gl_format (GdkMemoryFormat  format,
  * @gles: TRUE for GLES, FALSE for GL
  * @out_actual_format: The actual RGBA format
  * @out_internal_format: the GL internal format
+ * @out_internal_srgb_format: the GL internal format to use for automatic
+ *   sRGB<=>linear conversion
  * @out_format: the GL format
  * @out_type: the GL type
  * @out_swizzle: The swizzle to use 
@@ -1580,6 +1655,7 @@ gdk_memory_format_gl_rgba_format (GdkMemoryFormat  format,
                                   gboolean         gles,
                                   GdkMemoryFormat *out_actual_format,
                                   GLint           *out_internal_format,
+                                  GLint           *out_internal_srgb_format,
                                   GLenum          *out_format,
                                   GLenum          *out_type,
                                   GLint            out_swizzle[4])
@@ -1594,6 +1670,7 @@ gdk_memory_format_gl_rgba_format (GdkMemoryFormat  format,
     *out_internal_format = memory_formats[actual].gl.internal_gles_format;
   else
     *out_internal_format = memory_formats[actual].gl.internal_gl_format;
+  *out_internal_srgb_format = memory_formats[actual].gl.internal_srgb_format;
   *out_format = memory_formats[actual].gl.format;
   *out_type = memory_formats[actual].gl.type;
   memcpy (out_swizzle, memory_formats[format].gl.rgba_swizzle, sizeof(GLint) * 4);
@@ -1647,6 +1724,14 @@ gdk_memory_format_vk_format (GdkMemoryFormat     format,
   return memory_formats[format].vk_format;
 }
 
+/* Gets the matching SRGB version of a VkFormat
+ * Returns VK_FORMAT_UNDEFINED if none exists */
+VkFormat
+gdk_memory_format_vk_srgb_format (GdkMemoryFormat format)
+{
+  return memory_formats[format].vk_srgb_format;
+}
+
 /* Vulkan version of gdk_memory_format_gl_rgba_format()
  * Returns VK_FORMAT_UNDEFINED on failure */
 VkFormat
@@ -1748,6 +1833,10 @@ gdk_memory_convert (guchar              *dest_data,
 
   g_assert (dest_format < GDK_MEMORY_N_FORMATS);
   g_assert (src_format < GDK_MEMORY_N_FORMATS);
+  /* We don't allow overlap here. If you want to do in-place color state conversions,
+   * use gdk_memory_convert_color_state.
+   */
+  g_assert (dest_data + height * dest_stride < src_data || src_data + height * src_stride < dest_data);
 
   if (src_format == dest_format)
     {
@@ -1833,3 +1922,201 @@ gdk_memory_convert (guchar              *dest_data,
 
   g_free (tmp);
 }
+
+static const guchar srgb_lookup[] = {
+  0, 12, 21, 28, 33, 38, 42, 46, 49, 52, 55, 58, 61, 63, 66, 68,
+  70, 73, 75, 77, 79, 81, 82, 84, 86, 88, 89, 91, 93, 94, 96, 97,
+  99, 100, 102, 103, 104, 106, 107, 109, 110, 111, 112, 114, 115, 116, 117, 118,
+  120, 121, 122, 123, 124, 125, 126, 127, 129, 130, 131, 132, 133, 134, 135, 136,
+  137, 138, 139, 140, 141, 142, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151,
+  151, 152, 153, 154, 155, 156, 157, 157, 158, 159, 160, 161, 161, 162, 163, 164,
+  165, 165, 166, 167, 168, 168, 169, 170, 171, 171, 172, 173, 174, 174, 175, 176,
+  176, 177, 178, 179, 179, 180, 181, 181, 182, 183, 183, 184, 185, 185, 186, 187,
+  187, 188, 189, 189, 190, 191, 191, 192, 193, 193, 194, 194, 195, 196, 196, 197,
+  197, 198, 199, 199, 200, 201, 201, 202, 202, 203, 204, 204, 205, 205, 206, 206,
+  207, 208, 208, 209, 209, 210, 210, 211, 212, 212, 213, 213, 214, 214, 215, 215,
+  216, 217, 217, 218, 218, 219, 219, 220, 220, 221, 221, 222, 222, 223, 223, 224,
+  224, 225, 226, 226, 227, 227, 228, 228, 229, 229, 230, 230, 231, 231, 232, 232,
+  233, 233, 234, 234, 235, 235, 236, 236, 237, 237, 237, 238, 238, 239, 239, 240,
+  240, 241, 241, 242, 242, 243, 243, 244, 244, 245, 245, 245, 246, 246, 247, 247,
+  248, 248, 249, 249, 250, 250, 251, 251, 251, 252, 252, 253, 253, 254, 254, 255
+};
+
+static const guchar srgb_inverse_lookup[] = {
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3,
+  3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7,
+  7, 7, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12,
+  13, 13, 13, 14, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 19, 19,
+  20, 20, 21, 22, 22, 23, 23, 24, 24, 25, 26, 26, 27, 27, 28, 29,
+  29, 30, 31, 31, 32, 33, 33, 34, 35, 36, 36, 37, 38, 38, 39, 40,
+  41, 42, 42, 43, 44, 45, 46, 47, 47, 48, 49, 50, 51, 52, 53, 54,
+  55, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70,
+  71, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84, 85, 87, 88,
+  89, 90, 92, 93, 94, 95, 97, 98, 99, 101, 102, 103, 105, 106, 107, 109,
+  110, 112, 113, 114, 116, 117, 119, 120, 122, 123, 125, 126, 128, 129, 131, 132,
+  134, 135, 137, 139, 140, 142, 144, 145, 147, 148, 150, 152, 153, 155, 157, 159,
+  160, 162, 164, 166, 167, 169, 171, 173, 175, 176, 178, 180, 182, 184, 186, 188,
+  190, 192, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 218, 220,
+  222, 224, 226, 228, 230, 232, 235, 237, 239, 241, 243, 245, 248, 250, 252, 255
+};
+
+static void
+convert_srgb_to_srgb_linear (guchar *data,
+                             gsize   n)
+{
+  for (gsize i = 0; i < n; i++)
+    {
+      guint8 r = data[0];
+      guint8 g = data[1];
+      guint8 b = data[2];
+      guchar a = data[3];
+      float f = a / 255.0;
+      if (a < 255)
+        {
+          r = r / f;
+          g = g / f;
+          b = b / f;
+        }
+      r = srgb_inverse_lookup[r];
+      g = srgb_inverse_lookup[g];
+      b = srgb_inverse_lookup[b];
+
+      data[0] = r * f;
+      data[1] = g * f;
+      data[2] = b * f;
+      data += 4;
+    }
+}
+
+static void
+convert_srgb_linear_to_srgb (guchar *data,
+                             gsize   n)
+{
+  for (gsize i = 0; i < n; i++)
+    {
+      guint8 r = data[0];
+      guint8 g = data[1];
+      guint8 b = data[2];
+      guchar a = data[3];
+      float f = a / 255.0;
+      if (a < 255)
+        {
+          r = r / f;
+          g = g / f;
+          b = b / f;
+        }
+      r = srgb_lookup[r];
+      g = srgb_lookup[g];
+      b = srgb_lookup[b];
+
+      data[0] = r * f;
+      data[1] = g * f;
+      data[2] = b * f;
+      data += 4;
+    }
+}
+
+static void
+convert_srgb_to_srgb_linear_in_place (guchar *data,
+                                      gsize   stride,
+                                      gsize   width,
+                                      gsize   height)
+{
+  if (stride == width * 4)
+    {
+      convert_srgb_to_srgb_linear (data, height * width);
+    }
+  else
+    {
+      for (gsize y = 0; y < height; y++)
+        {
+          convert_srgb_to_srgb_linear (data, width);
+          data += stride;
+        }
+    }
+}
+
+static void
+convert_srgb_linear_to_srgb_in_place (guchar *data,
+                                      gsize   stride,
+                                      gsize   width,
+                                      gsize   height)
+{
+  if (stride == width * 4)
+    {
+      convert_srgb_linear_to_srgb (data, height * width);
+    }
+  else
+    {
+      for (gsize y = 0; y < height; y++)
+        {
+          convert_srgb_linear_to_srgb (data, width);
+          data += stride;
+        }
+    }
+}
+
+typedef void (* StepFunc) (float  s0, float  s1, float  s2,
+                           float *d0, float *d1, float *d2);
+
+void
+gdk_memory_convert_color_state (guchar          *data,
+                                gsize            stride,
+                                GdkMemoryFormat  format,
+                                GdkColorState   *src_color_state,
+                                GdkColorState   *dest_color_state,
+                                gsize            width,
+                                gsize            height)
+{
+  if (format == GDK_MEMORY_B8G8R8A8_PREMULTIPLIED &&
+      src_color_state == GDK_COLOR_STATE_SRGB &&
+      dest_color_state == GDK_COLOR_STATE_SRGB_LINEAR)
+    {
+      convert_srgb_to_srgb_linear_in_place (data, stride, width, height);
+    }
+  else if (format == GDK_MEMORY_B8G8R8A8_PREMULTIPLIED &&
+           src_color_state == GDK_COLOR_STATE_SRGB_LINEAR &&
+           dest_color_state == GDK_COLOR_STATE_SRGB)
+    {
+      convert_srgb_linear_to_srgb_in_place (data, stride, width, height);
+    }
+  else
+    {
+      /* General case, treat it just like gdk_memory_convert */
+
+      const GdkMemoryFormatDescription *desc = &memory_formats[format];
+      StepFunc func;
+      float *tmp;
+
+      if (src_color_state == GDK_COLOR_STATE_SRGB &&
+          dest_color_state == GDK_COLOR_STATE_SRGB_LINEAR)
+        func = gtk_rgb_to_linear_srgb;
+      else if (src_color_state == GDK_COLOR_STATE_SRGB_LINEAR &&
+               dest_color_state == GDK_COLOR_STATE_SRGB)
+        func = gtk_linear_srgb_to_rgb;
+      else
+        return;
+
+      tmp = g_new (float, width * 4);
+
+      for (gsize y = 0; y < height; y++)
+        {
+          desc->to_float (tmp, data, width);
+
+          if (desc->alpha == GDK_MEMORY_ALPHA_PREMULTIPLIED)
+            unpremultiply (tmp, width);
+
+          for (gsize x = 0; x < 4 * width; x += 4)
+            func (tmp[x], tmp[x+1], tmp[x+2], &tmp[x], &tmp[x+1], &tmp[x+2]);
+
+          if (desc->alpha != GDK_MEMORY_ALPHA_STRAIGHT)
+            premultiply (tmp, width);
+
+          desc->from_float (data, tmp, width);
+          data += stride;
+        }
+
+      g_free (tmp);
+    }
+}

gdk/gdkmemoryformatprivate.h

@@ -57,6 +57,7 @@ GdkMemoryFormat         gdk_memory_depth_get_alpha_format   (GdkMemoryDepth
 void                    gdk_memory_format_gl_format         (GdkMemoryFormat             format,
                                                              gboolean                    gles,
                                                              GLint                      *out_internal_format,
+                                                             GLint                      *out_internal_srgb_format,
                                                              GLenum                     *out_format,
                                                              GLenum                     *out_type,
                                                              GLint                       out_swizzle[4]);
@@ -64,12 +65,14 @@ gboolean                gdk_memory_format_gl_rgba_format    (GdkMemoryFormat
                                                              gboolean                    gles,
                                                              GdkMemoryFormat            *out_actual_format,
                                                              GLint                      *out_internal_format,
+                                                             GLint                      *out_internal_srgb_format,
                                                              GLenum                     *out_format,
                                                              GLenum                     *out_type,
                                                              GLint                       out_swizzle[4]);
 #ifdef GDK_RENDERING_VULKAN
 VkFormat                gdk_memory_format_vk_format         (GdkMemoryFormat             format,
                                                              VkComponentMapping         *out_swizzle);
+VkFormat                gdk_memory_format_vk_srgb_format    (GdkMemoryFormat             format);
 VkFormat                gdk_memory_format_vk_rgba_format    (GdkMemoryFormat             format,
                                                              GdkMemoryFormat            *out_rgba_format,
                                                              VkComponentMapping         *out_swizzle);
@@ -85,6 +88,13 @@ void                    gdk_memory_convert                  (guchar
                                                              GdkMemoryFormat             src_format,
                                                              gsize                       width,
                                                              gsize                       height);
+void                    gdk_memory_convert_color_state      (guchar                     *data,
+                                                             gsize                       stride,
+                                                             GdkMemoryFormat             format,
+                                                             GdkColorState              *src_color_state,
+                                                             GdkColorState              *dest_color_state,
+                                                             gsize                       width,
+                                                             gsize                       height);
 
 
 G_END_DECLS

gdk/gdkmemorytexture.c

@@ -22,6 +22,7 @@
 #include "gdkmemorytextureprivate.h"
 
 #include "gdkmemoryformatprivate.h"
+#include "gdkcolorstateprivate.h"
 #include "gsk/gl/fp16private.h"
 
 /**
@@ -131,11 +132,15 @@ gdk_memory_sanitize (GBytes          *bytes,
  * @bytes: the `GBytes` containing the pixel data
  * @stride: rowstride for the data
  *
- * Creates a new texture for a blob of image data.
+ * Creates a new texture for a blob of sRGB image data.
  *
  * The `GBytes` must contain @stride × @height pixels
  * in the given format.
  *
+ * The data is assumed to be in SRGB. See
+ * [constructor@Gdk.MemoryTexutre.new_with_color_state]
+ * for data in other color states.
+ *
  * Returns: (type GdkMemoryTexture): A newly-created `GdkTexture`
  */
 GdkTexture *
@@ -144,11 +149,43 @@ gdk_memory_texture_new (int              width,
                         GdkMemoryFormat  format,
                         GBytes          *bytes,
                         gsize            stride)
+{
+  return  gdk_memory_texture_new_with_color_state (width, height, format,
+                                                   GDK_COLOR_STATE_SRGB,
+                                                   bytes, stride);
+}
+
+/**
+ * gdk_memory_texture_new_with_color_state:
+ * @width: the width of the texture
+ * @height: the height of the texture
+ * @format: the format of the data
+ * @color_state: the `GdkColorState` of the data
+ * @bytes: the `GBytes` containing the pixel data
+ * @stride: rowstride for the data
+ *
+ * Creates a new texture for a blob of image data.
+ *
+ * The `GBytes` must contain @stride x @height pixels
+ * in the given format and color state.
+ *
+ * Returns: A newly-created `GdkTexture`
+ *
+ * Since: 4.16
+ */
+GdkTexture *
+gdk_memory_texture_new_with_color_state (int              width,
+                                         int              height,
+                                         GdkMemoryFormat  format,
+                                         GdkColorState   *color_state,
+                                         GBytes          *bytes,
+                                         gsize            stride)
 {
   GdkMemoryTexture *self;
 
   g_return_val_if_fail (width > 0, NULL);
   g_return_val_if_fail (height > 0, NULL);
+  g_return_val_if_fail (color_state != NULL, NULL);
   g_return_val_if_fail (bytes != NULL, NULL);
   g_return_val_if_fail (stride >= width * gdk_memory_format_bytes_per_pixel (format), NULL);
   /* needs to be this complex to support subtexture of the bottom right part */
@@ -159,6 +196,7 @@ gdk_memory_texture_new (int              width,
   self = g_object_new (GDK_TYPE_MEMORY_TEXTURE,
                        "width", width,
                        "height", height,
+                       "color-state", color_state,
                        NULL);
 
   GDK_TEXTURE (self)->format = format;
@@ -191,11 +229,12 @@ gdk_memory_texture_new_subtexture (GdkMemoryTexture  *source,
   size = source->stride * (height - 1) + width * bpp;
   bytes = g_bytes_new_from_bytes (source->bytes, offset, size);
 
-  result = gdk_memory_texture_new (width,
-                                   height,
-                                   texture->format,
-                                   bytes,
-                                   source->stride);
+  result = gdk_memory_texture_new_with_color_state (width,
+                                                    height,
+                                                    texture->format,
+                                                    texture->color_state,
+                                                    bytes,
+                                                    source->stride);
   g_bytes_unref (bytes);
 
   return result;
@@ -219,11 +258,12 @@ gdk_memory_texture_from_texture (GdkTexture *texture)
 
   gdk_texture_do_download (texture, texture->format, data, stride);
   bytes = g_bytes_new_take (data, stride * texture->height);
-  result = gdk_memory_texture_new (texture->width,
-                                   texture->height,
-                                   texture->format,
-                                   bytes,
-                                   stride);
+  result = gdk_memory_texture_new_with_color_state (texture->width,
+                                                    texture->height,
+                                                    texture->format,
+                                                    texture->color_state,
+                                                    bytes,
+                                                    stride);
   g_bytes_unref (bytes);
 
   return GDK_MEMORY_TEXTURE (result);

gdk/gdkmemorytexture.h

@@ -68,6 +68,14 @@ GdkTexture *            gdk_memory_texture_new              (int
                                                              GBytes            *bytes,
                                                              gsize              stride);
 
+GDK_AVAILABLE_IN_4_16
+GdkTexture *            gdk_memory_texture_new_with_color_state (int              width,
+                                                                 int              height,
+                                                                 GdkMemoryFormat  format,
+                                                                 GdkColorState   *color_state,
+                                                                 GBytes          *bytes,
+                                                                 gsize            stride);
+
 
 G_END_DECLS
 

gdk/gdksurface.c

@@ -1148,9 +1148,11 @@ gdk_surface_ensure_egl_surface (GdkSurface *self,
 
   g_return_if_fail (priv->egl_native_window != NULL);
 
+  if (gdk_display_get_egl_config_high_depth (display) == gdk_display_get_egl_config (display))
+    high_depth = FALSE;
+
   if (priv->egl_surface_high_depth != high_depth &&
-      priv->egl_surface != NULL &&
-      gdk_display_get_egl_config_high_depth (display) != gdk_display_get_egl_config (display))
+      priv->egl_surface != NULL)
     {
       gdk_gl_context_clear_current_if_surface (self);
       eglDestroySurface (gdk_display_get_egl_display (display), priv->egl_surface);
@@ -1159,16 +1161,35 @@ gdk_surface_ensure_egl_surface (GdkSurface *self,
 
   if (priv->egl_surface == NULL)
     {
+      EGLint attribs[4];
+      int i;
+
+      i = 0;
+      if (!high_depth && display->have_egl_gl_colorspace)
+        {
+          attribs[i++] = EGL_GL_COLORSPACE_KHR;
+          attribs[i++] = EGL_GL_COLORSPACE_SRGB_KHR;
+        }
+      g_assert (i < G_N_ELEMENTS (attribs));
+      attribs[i++] = EGL_NONE;
+
       priv->egl_surface = eglCreateWindowSurface (gdk_display_get_egl_display (display),
                                                   high_depth ? gdk_display_get_egl_config_high_depth (display)
                                                              : gdk_display_get_egl_config (display),
                                                   (EGLNativeWindowType) priv->egl_native_window,
-                                                  NULL);
+                                                  attribs);
       priv->egl_surface_high_depth = high_depth;
+      self->is_srgb = !high_depth && display->have_egl_gl_colorspace;
     }
 #endif
 }
 
+gboolean
+gdk_surface_get_gl_is_srgb (GdkSurface *self)
+{
+  return self->is_srgb;
+}
+
 GdkGLContext *
 gdk_surface_get_paint_gl_context (GdkSurface  *surface,
                                   GError     **error)

gdk/gdksurfaceprivate.h

@@ -70,6 +70,7 @@ struct _GdkSurface
   guint shortcuts_inhibited : 1;
   guint request_motion : 1;
   guint has_pointer : 1;
+  guint is_srgb : 1;
 
   guint request_motion_id;
 
@@ -302,6 +303,8 @@ void                    gdk_surface_ensure_egl_surface          (GdkSurface
                                                                  gboolean                hdr);
 gpointer /*EGLSurface*/ gdk_surface_get_egl_surface             (GdkSurface             *self);
 
+gboolean                gdk_surface_get_gl_is_srgb              (GdkSurface             *self);
+
 void                    gdk_surface_set_widget                  (GdkSurface             *self,
                                                                  gpointer                widget);
 gpointer                gdk_surface_get_widget                  (GdkSurface             *self);

gdk/gdktexture.c

@@ -44,6 +44,7 @@
 #include "gdkmemorytextureprivate.h"
 #include "gdkpaintable.h"
 #include "gdksnapshot.h"
+#include "gdkcolorstateprivate.h"
 
 #include <graphene.h>
 #include "loaders/gdkpngprivate.h"
@@ -69,6 +70,7 @@ enum {
   PROP_0,
   PROP_WIDTH,
   PROP_HEIGHT,
+  PROP_COLOR_STATE,
 
   N_PROPS
 };
@@ -282,6 +284,12 @@ gdk_texture_set_property (GObject      *gobject,
       self->height = g_value_get_int (value);
       break;
 
+    case PROP_COLOR_STATE:
+      if (self->color_state)
+        gdk_color_state_unref (self->color_state);
+      self->color_state = gdk_color_state_ref (g_value_get_boxed (value));
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
       break;
@@ -306,6 +314,10 @@ gdk_texture_get_property (GObject    *gobject,
       g_value_set_int (value, self->height);
       break;
 
+    case PROP_COLOR_STATE:
+      g_value_set_boxed (value, self->color_state);
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
       break;
@@ -344,6 +356,8 @@ gdk_texture_dispose (GObject *object)
 
   gdk_texture_clear_render_data (self);
 
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
+
   G_OBJECT_CLASS (gdk_texture_parent_class)->dispose (object);
 }
 
@@ -388,12 +402,28 @@ gdk_texture_class_init (GdkTextureClass *klass)
                       G_PARAM_STATIC_STRINGS |
                       G_PARAM_EXPLICIT_NOTIFY);
 
+  /**
+   * GdkTexture:color-state: (attributes org.gtk.Property.get=gdk_texture_get_color_state)
+   *
+   * The color state of the texture.
+   *
+   * Since: 4.16
+   */
+  properties[PROP_COLOR_STATE] =
+    g_param_spec_boxed ("color-state", NULL, NULL,
+                        GDK_TYPE_COLOR_STATE,
+                        G_PARAM_READWRITE |
+                        G_PARAM_CONSTRUCT_ONLY |
+                        G_PARAM_STATIC_STRINGS |
+                        G_PARAM_EXPLICIT_NOTIFY);
+
   g_object_class_install_properties (gobject_class, N_PROPS, properties);
 }
 
 static void
 gdk_texture_init (GdkTexture *self)
 {
+  self->color_state = GDK_COLOR_STATE_SRGB;
 }
 
 /**
@@ -435,6 +465,30 @@ gdk_texture_new_for_surface (cairo_surface_t *surface)
   return texture;
 }
 
+static GdkColorState *
+gdk_color_state_from_pixbuf (GdkPixbuf *pixbuf)
+{
+  const char *icc_profile_base64;
+  GdkColorState *color_state = NULL;
+
+  icc_profile_base64 = gdk_pixbuf_get_option (pixbuf, "icc-profile");
+  if (icc_profile_base64)
+    {
+      guchar *icc_data;
+      gsize icc_len;
+      GBytes *bytes;
+
+      icc_data = g_base64_decode (icc_profile_base64, &icc_len);
+      bytes = g_bytes_new_take (icc_data, icc_len);
+      color_state = gdk_color_state_new_from_icc_profile (bytes, NULL);
+      g_bytes_unref (bytes);
+    }
+  if (!color_state)
+    color_state = GDK_COLOR_STATE_SRGB;
+
+  return color_state;
+}
+
 /**
  * gdk_texture_new_for_pixbuf:
  * @pixbuf: a `GdkPixbuf`
@@ -452,24 +506,31 @@ gdk_texture_new_for_pixbuf (GdkPixbuf *pixbuf)
 {
   GdkTexture *texture;
   GBytes *bytes;
+  GdkColorState *color_state;
 
   g_return_val_if_fail (GDK_IS_PIXBUF (pixbuf), NULL);
 
+  color_state = gdk_color_state_from_pixbuf (pixbuf);
+
   bytes = g_bytes_new_with_free_func (gdk_pixbuf_get_pixels (pixbuf),
                                       gdk_pixbuf_get_height (pixbuf)
                                       * (gsize) gdk_pixbuf_get_rowstride (pixbuf),
                                       g_object_unref,
                                       g_object_ref (pixbuf));
-  texture = gdk_memory_texture_new (gdk_pixbuf_get_width (pixbuf),
-                                    gdk_pixbuf_get_height (pixbuf),
-                                    gdk_pixbuf_get_has_alpha (pixbuf)
-                                    ? GDK_MEMORY_GDK_PIXBUF_ALPHA
-                                    : GDK_MEMORY_GDK_PIXBUF_OPAQUE,
-                                    bytes,
-                                    gdk_pixbuf_get_rowstride (pixbuf));
+
+  texture = gdk_memory_texture_new_with_color_state (gdk_pixbuf_get_width (pixbuf),
+                                                     gdk_pixbuf_get_height (pixbuf),
+                                                     gdk_pixbuf_get_has_alpha (pixbuf)
+                                                     ? GDK_MEMORY_GDK_PIXBUF_ALPHA
+                                                     : GDK_MEMORY_GDK_PIXBUF_OPAQUE,
+                                                     color_state,
+                                                     bytes,
+                                                     gdk_pixbuf_get_rowstride (pixbuf));
 
   g_bytes_unref (bytes);
 
+  gdk_color_state_unref (color_state);
+
   return texture;
 }
 
@@ -727,6 +788,23 @@ gdk_texture_get_height (GdkTexture *texture)
   return texture->height;
 }
 
+/**
+ * gdk_texture_get_color_state: (attributes org.gtk.Method.get_property=color-state)
+ * @texture: a `GdkTexture`
+ *
+ * Returns the color state associsated with @texture.
+ *
+ * Returns: (transfer none): the color state of the `GdkTexture`
+ *
+ * Since: 4.16
+ */
+GdkColorState *
+gdk_texture_get_color_state (GdkTexture *texture)
+{
+  g_return_val_if_fail (GDK_IS_TEXTURE (texture), NULL);
+
+  return texture->color_state;
+}
 void
 gdk_texture_do_download (GdkTexture      *texture,
                          GdkMemoryFormat  format,

gdk/gdktexture.h

@@ -83,6 +83,9 @@ int                     gdk_texture_get_height                 (GdkTexture
 GDK_AVAILABLE_IN_4_10
 GdkMemoryFormat         gdk_texture_get_format                 (GdkTexture      *self) G_GNUC_PURE;
 
+GDK_AVAILABLE_IN_4_16
+GdkColorState *         gdk_texture_get_color_state            (GdkTexture      *self);
+
 GDK_AVAILABLE_IN_ALL
 void                    gdk_texture_download                   (GdkTexture      *texture,
                                                                 guchar          *data,

gdk/gdktextureprivate.h

@@ -26,6 +26,8 @@ struct _GdkTexture
   int width;
   int height;
 
+  GdkColorState *color_state;
+
   gpointer render_key;
   gpointer render_data;
   GDestroyNotify render_notify;

gdk/gdktypes.h

@@ -74,6 +74,7 @@ typedef cairo_rectangle_int_t         GdkRectangle;
 
 /* Forward declarations of commonly used types */
 typedef struct _GdkRGBA               GdkRGBA;
+typedef struct _GdkColorState         GdkColorState;
 typedef struct _GdkContentFormats     GdkContentFormats;
 typedef struct _GdkContentProvider    GdkContentProvider;
 typedef struct _GdkCursor             GdkCursor;

gdk/gdkvulkancontext.c

@@ -884,7 +884,9 @@ gdk_vulkan_context_real_init (GInitable     *initable,
           switch ((int) formats[i].format)
             {
               case VK_FORMAT_B8G8R8A8_UNORM:
-                if (priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_UNDEFINED)
+              case VK_FORMAT_B8G8R8A8_SRGB:
+                if (priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_UNDEFINED ||
+                    priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_B8G8R8A8_UNORM)
                   {
                     priv->formats[GDK_MEMORY_U8].vk_format = formats[i];
                     priv->formats[GDK_MEMORY_U8].gdk_format = GDK_MEMORY_B8G8R8A8_PREMULTIPLIED;
@@ -893,7 +895,9 @@ gdk_vulkan_context_real_init (GInitable     *initable,
                 break;
 
               case VK_FORMAT_R8G8B8A8_UNORM:
-                if (priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_UNDEFINED)
+              case VK_FORMAT_R8G8B8A8_SRGB:
+                if (priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_UNDEFINED ||
+                    priv->formats[GDK_MEMORY_U8].vk_format.format == VK_FORMAT_R8G8B8A8_UNORM)
                   {
                     priv->formats[GDK_MEMORY_U8].vk_format = formats[i];
                     priv->formats[GDK_MEMORY_U8].gdk_format = GDK_MEMORY_R8G8B8A8_PREMULTIPLIED;

gdk/gen-gdk-gresources-xml.py

@@ -26,6 +26,8 @@ xml = '''<?xml version='1.0' encoding='UTF-8'?>
 <gresources>
   <gresource prefix='/org/gtk/libgdk'>
     <file alias='cursor/default'>default_cursor.png</file>
+    <file alias='icc/srgb.icc'>srgb.icc</file>
+    <file alias='icc/srgb-linear.icc'>srgb-linear.icc</file>
 '''
 
 def get_files(subdir,extension):

gdk/loaders/gdkjpeg.c

@@ -24,6 +24,8 @@
 #include <glib/gi18n-lib.h>
 #include "gdktexture.h"
 #include "gdktexturedownloaderprivate.h"
+#include "gdkcolorstateprivate.h"
+#include "gdkmemorytextureprivate.h"
 
 #include "gdkprofilerprivate.h"
 
@@ -74,7 +76,51 @@ output_message_handler (j_common_ptr cinfo)
 }
 
 /* }}} */
-/* {{{ Format conversion */
+/* {{{ Color profile handling */
+
+static GdkColorState *
+gdk_jpeg_get_color_state (struct jpeg_decompress_struct *info)
+{
+  GdkColorState *color_state;
+  JOCTET *icc_data;
+  unsigned int icc_len;
+
+  if (jpeg_read_icc_profile (info, &icc_data, &icc_len))
+    {
+      GBytes *icc_bytes = g_bytes_new_with_free_func (icc_data, icc_len, free, icc_data);
+      color_state = gdk_color_state_new_from_icc_profile (icc_bytes, NULL);
+      g_bytes_unref (icc_bytes);
+      if (!color_state)
+        {
+          g_debug ("Failed to load icc profile, assuming SRGB");
+          color_state = GDK_COLOR_STATE_SRGB;
+        }
+    }
+  else
+    color_state = GDK_COLOR_STATE_SRGB;
+
+  return color_state;
+}
+
+static void
+gdk_jpeg_set_color_state (struct jpeg_compress_struct *info,
+                          GdkColorState               *color_state)
+{
+  GBytes *bytes;
+
+  bytes = gdk_color_state_save_to_icc_profile (color_state, NULL);
+
+  if (bytes)
+    {
+      jpeg_write_icc_profile (info,
+                              g_bytes_get_data (bytes, NULL),
+                              g_bytes_get_size (bytes));
+      g_bytes_unref (bytes);
+    }
+}
+
+/* }}} */
+ /* {{{ Format conversion */
 
 static void
 convert_grayscale_to_rgb (guchar *data,
@@ -131,7 +177,7 @@ convert_cmyk_to_rgba (guchar *data,
     }
 }
 
- /* }}} */
+/* }}} */
 /* {{{ Public API */
 
 GdkTexture *
@@ -146,6 +192,7 @@ gdk_load_jpeg (GBytes  *input_bytes,
   GBytes *bytes;
   GdkTexture *texture;
   GdkMemoryFormat format;
+  GdkColorState *color_state;
   G_GNUC_UNUSED guint64 before = GDK_PROFILER_CURRENT_TIME;
 
   info.err = jpeg_std_error (&jerr.pub);
@@ -169,6 +216,9 @@ gdk_load_jpeg (GBytes  *input_bytes,
                 g_bytes_get_data (input_bytes, NULL),
                 g_bytes_get_size (input_bytes));
 
+  /* save color space */
+  jpeg_save_markers (&info, JPEG_APP0 + 2, 0xFFFF);
+
   jpeg_read_header (&info, TRUE);
   jpeg_start_decompress (&info);
 
@@ -226,19 +276,23 @@ gdk_load_jpeg (GBytes  *input_bytes,
       g_assert_not_reached ();
     }
 
+  color_state = gdk_jpeg_get_color_state (&info);
+
   jpeg_finish_decompress (&info);
   jpeg_destroy_decompress (&info);
 
   bytes = g_bytes_new_take (data, stride * height);
 
-  texture = gdk_memory_texture_new (width, height,
-                                    format,
-                                    bytes, stride);
+  texture = gdk_memory_texture_new_with_color_state (width, height,
+                                                     format,
+                                                     color_state,
+                                                     bytes, stride);
 
+  gdk_color_state_unref (color_state);
   g_bytes_unref (bytes);
 
   gdk_profiler_end_mark (before, "Load jpeg", NULL);
- 
+
   return texture;
 }
 
@@ -257,9 +311,11 @@ gdk_save_jpeg (GdkTexture *texture)
   gsize texstride;
   guchar *row;
   int width, height;
+  GdkColorState *color_state;
 
   width = gdk_texture_get_width (texture);
   height = gdk_texture_get_height (texture);
+  color_state = gdk_texture_get_color_state (texture);
 
   info.err = jpeg_std_error (&jerr.pub);
   jerr.pub.error_exit = fatal_error_handler;
@@ -298,6 +354,8 @@ gdk_save_jpeg (GdkTexture *texture)
 
   jpeg_start_compress (&info, TRUE);
 
+  gdk_jpeg_set_color_state (&info, color_state);
+
   while (info.next_scanline < info.image_height)
     {
       row = (guchar *) texdata + info.next_scanline * texstride;

gdk/loaders/gdkpng.c

@@ -20,11 +20,14 @@
 #include "gdkpngprivate.h"
 
 #include <glib/gi18n-lib.h>
+#include "gdkcolorstateprivate.h"
+#include "gdkcolorstateprivate.h"
 #include "gdkmemoryformatprivate.h"
 #include "gdkmemorytexture.h"
 #include "gdkprofilerprivate.h"
 #include "gdktexturedownloaderprivate.h"
 #include "gsk/gl/fp16private.h"
+
 #include <png.h>
 #include <stdio.h>
 
@@ -126,6 +129,143 @@ png_simple_warning_callback (png_structp     png,
 {
 }
 
+/* }}} */
+/* {{{ Color profile handling */
+
+typedef struct
+{
+  gboolean cicp_chunk_read;
+  int color_primaries;
+  int transfer_function;
+  int matrix_coefficients;
+  int full_range;
+} CICPData;
+
+static int
+png_read_chunk_func (png_structp        png,
+                     png_unknown_chunkp chunk)
+{
+  if (strcmp ((char *) chunk->name, "cICP") == 0 &&
+      chunk->size == 4)
+    {
+      CICPData *cicp = png_get_user_chunk_ptr (png);
+
+      cicp->cicp_chunk_read = TRUE;
+
+      cicp->color_primaries = chunk->data[0];
+      cicp->transfer_function = chunk->data[1];
+      cicp->matrix_coefficients = chunk->data[2];
+      cicp->full_range = chunk->data[3];
+
+      return 1;
+    }
+
+  return 0;
+}
+
+static GdkColorState *
+gdk_png_get_color_state (png_struct *png,
+                         png_info   *info)
+{
+  GdkColorState *color_state;
+  guchar *icc_data;
+  png_uint_32 icc_len;
+  char *name;
+  CICPData *cicp;
+  int intent;
+
+  cicp = png_get_user_chunk_ptr (png);
+
+  if (cicp->cicp_chunk_read)
+    {
+      color_state = gdk_color_state_new_from_cicp_data (cicp->color_primaries,
+                                                        cicp->transfer_function,
+                                                        cicp->matrix_coefficients,
+                                                        cicp->full_range);
+      if (color_state)
+        {
+          g_debug ("Color state from cICP data: %s", gdk_color_state_get_name (color_state));
+          return color_state;
+        }
+      else
+        {
+          g_debug ("Failed to create color state from cICP data: %d/%d/%d %d",
+                   cicp->color_primaries,
+                   cicp->transfer_function,
+                   cicp->matrix_coefficients,
+                   cicp->full_range);
+        }
+    }
+
+  if (png_get_iCCP (png, info, &name, NULL, &icc_data, &icc_len))
+    {
+      GBytes *bytes = g_bytes_new (icc_data, icc_len);
+
+      color_state = gdk_color_state_new_from_icc_profile (bytes, NULL);
+
+      g_bytes_unref (bytes);
+
+      if (color_state)
+        return color_state;
+    }
+
+  if (png_get_sRGB (png, info, &intent))
+    return GDK_COLOR_STATE_SRGB;
+
+  /* If neither of those is valid, the result is sRGB */
+  if (!png_get_valid (png, info, PNG_INFO_gAMA) &&
+      !png_get_valid (png, info, PNG_INFO_cHRM))
+    return GDK_COLOR_STATE_SRGB;
+
+  g_debug ("Failed to find color state, assuming SRGB");
+
+  return GDK_COLOR_STATE_SRGB;
+}
+
+static void
+gdk_png_set_color_state (png_struct    *png,
+                         png_info      *info,
+                         GdkColorState *color_state,
+                         png_byte      *chunk_data)
+{
+  int cp, tc, mc;
+  gboolean fr;
+  GBytes *bytes;
+
+  if (gdk_color_state_save_to_cicp_data (color_state, &cp, &tc, &mc, &fr, NULL))
+    {
+      png_unknown_chunk chunk = {
+        .name = { 'c', 'I', 'C', 'P', '\0' },
+        .data = chunk_data,
+        .size = 4,
+        .location = PNG_HAVE_IHDR,
+      };
+
+      chunk_data[0] = (png_byte)cp;
+      chunk_data[1] = (png_byte)tc;
+      chunk_data[2] = (png_byte)mc;
+      chunk_data[3] = (png_byte)fr;
+
+      png_set_unknown_chunks (png, info, &chunk, 1);
+    }
+
+  /* Since most tools don't understand cicp, we save an icc profile as well */
+  bytes = gdk_color_state_save_to_icc_profile (color_state, NULL);
+  if (bytes)
+    {
+      png_set_iCCP (png, info,
+                    "ICC profile",
+                    0,
+                    g_bytes_get_data (bytes, NULL),
+                    g_bytes_get_size (bytes));
+      g_bytes_unref (bytes);
+    }
+
+  /* For good measure, we add an sRGB chunk too */
+  if (color_state == GDK_COLOR_STATE_SRGB)
+    png_set_sRGB (png, info, PNG_sRGB_INTENT_PERCEPTUAL);
+}
+
 /* }}} */
 /* {{{ Public API */
 
@@ -147,8 +287,11 @@ gdk_load_png (GBytes      *bytes,
   guchar *buffer = NULL;
   guchar **row_pointers = NULL;
   GBytes *out_bytes;
+  GdkColorState *color_state;
   GdkTexture *texture;
   int bpp;
+  CICPData cicp = { FALSE, };
+
   G_GNUC_UNUSED gint64 before = GDK_PROFILER_CURRENT_TIME;
 
   io.data = (guchar *)g_bytes_get_data (bytes, &io.size);
@@ -169,6 +312,7 @@ gdk_load_png (GBytes      *bytes,
     g_error ("Out of memory");
 
   png_set_read_fn (png, &io, png_read_func);
+  png_set_read_user_chunk_fn (png, &cicp, png_read_chunk_func);
 
   if (sigsetjmp (png_jmpbuf (png), 1))
     {
@@ -266,6 +410,8 @@ gdk_load_png (GBytes      *bytes,
       return NULL;
     }
 
+  color_state = gdk_png_get_color_state (png, info);
+
   bpp = gdk_memory_format_bytes_per_pixel (format);
   if (!g_size_checked_mul (&stride, width, bpp) ||
       !g_size_checked_add (&stride, stride, (8 - stride % 8) % 8))
@@ -281,6 +427,7 @@ gdk_load_png (GBytes      *bytes,
 
   if (!buffer || !row_pointers)
     {
+      gdk_color_state_unref (color_state);
       g_free (buffer);
       g_free (row_pointers);
       png_destroy_read_struct (&png, &info, NULL);
@@ -297,8 +444,11 @@ gdk_load_png (GBytes      *bytes,
   png_read_end (png, info);
 
   out_bytes = g_bytes_new_take (buffer, height * stride);
-  texture = gdk_memory_texture_new (width, height, format, out_bytes, stride);
+  texture = gdk_memory_texture_new_with_color_state (width, height,
+                                                     format, color_state,
+                                                     out_bytes, stride);
   g_bytes_unref (out_bytes);
+  gdk_color_state_unref (color_state);
 
   if (options && png_get_text (png, info, &text, &num_texts))
     {
@@ -337,11 +487,14 @@ gdk_save_png (GdkTexture *texture)
   GBytes *bytes;
   gsize stride;
   const guchar *data;
+  GdkColorState *color_state;
   int png_format;
   int depth;
+  png_byte chunk_data[4];
 
   width = gdk_texture_get_width (texture);
   height = gdk_texture_get_height (texture);
+  color_state = gdk_texture_get_color_state (texture);
   format = gdk_texture_get_format (texture);
 
   switch (format)
@@ -436,6 +589,10 @@ gdk_save_png (GdkTexture *texture)
   /* 2^31-1 is the maximum size for PNG files */
   png_set_user_limits (png, (1u << 31) - 1, (1u << 31) - 1);
 
+  png_set_keep_unknown_chunks (png, PNG_HANDLE_CHUNK_ALWAYS, NULL, 0);
+
+  png_set_option (png, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
+
   info = png_create_info_struct (png);
   if (!info)
     {
@@ -465,6 +622,8 @@ gdk_save_png (GdkTexture *texture)
                 PNG_COMPRESSION_TYPE_DEFAULT,
                 PNG_FILTER_TYPE_DEFAULT);
 
+  gdk_png_set_color_state (png, info, color_state, chunk_data);
+
   png_write_info (png, info);
 
 #if G_BYTE_ORDER == G_LITTLE_ENDIAN

gdk/loaders/gdktiff.c

@@ -24,6 +24,7 @@
 #include "gdkmemorytexture.h"
 #include "gdkprofilerprivate.h"
 #include "gdktexturedownloaderprivate.h"
+#include "gdkcolorstateprivate.h"
 
 #include <tiffio.h>
 
@@ -219,6 +220,53 @@ tiff_open_write (GBytes **result)
                          NULL, NULL);
 }
 
+/* }}} */
+/* {{{ Color profile handling */
+
+static GdkColorState *
+gdk_tiff_get_color_state (TIFF *tiff)
+{
+  GdkColorState *color_state;
+  const char *icc_data;
+  guint icc_len;
+
+  if (TIFFGetField (tiff, TIFFTAG_ICCPROFILE, &icc_len, &icc_data))
+    {
+      GBytes *icc_bytes;
+
+      icc_bytes = g_bytes_new (icc_data, icc_len);
+      color_state = gdk_color_state_new_from_icc_profile (icc_bytes, NULL);
+      g_bytes_unref (icc_bytes);
+      if (!color_state)
+        {
+          g_debug ("Failed to load icc profile, assuming SRGB");
+          color_state = GDK_COLOR_STATE_SRGB;
+        }
+    }
+  else
+    color_state = GDK_COLOR_STATE_SRGB;
+
+  return color_state;
+}
+
+static void
+gdk_tiff_set_color_state (TIFF          *tiff,
+                          GdkColorState *color_state)
+{
+  GBytes *bytes;
+
+  bytes = gdk_color_state_save_to_icc_profile (color_state, NULL);
+
+  if (bytes)
+    {
+      TIFFSetField (tiff, TIFFTAG_ICCPROFILE,
+                    g_bytes_get_size (bytes),
+                    g_bytes_get_data (bytes, NULL));
+
+      g_bytes_unref (bytes);
+    }
+}
+
 /* }}} */
 /* {{{ Public API */
 
@@ -282,6 +330,7 @@ gdk_save_tiff (GdkTexture *texture)
   GBytes *bytes, *result = NULL;
   GdkTextureDownloader downloader;
   GdkMemoryFormat format;
+  GdkColorState *color_state;
   const FormatData *fdata = NULL;
 
   tif = tiff_open_write (&result);
@@ -289,6 +338,7 @@ gdk_save_tiff (GdkTexture *texture)
   width = gdk_texture_get_width (texture);
   height = gdk_texture_get_height (texture);
   format = gdk_texture_get_format (texture);
+  color_state = gdk_texture_get_color_state (texture);
   fdata = &format_data[format];
 
   if (fdata == NULL)
@@ -308,6 +358,8 @@ gdk_save_tiff (GdkTexture *texture)
   TIFFSetField (tif, TIFFTAG_PHOTOMETRIC, fdata->photometric);
   TIFFSetField (tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
 
+  gdk_tiff_set_color_state (tif, color_state);
+
   gdk_texture_downloader_init (&downloader, texture);
   gdk_texture_downloader_set_format (&downloader, fdata->format);
   bytes = gdk_texture_downloader_download_bytes (&downloader, &stride);
@@ -344,6 +396,7 @@ load_fallback (TIFF    *tif,
   int width, height;
   guchar *data;
   GBytes *bytes;
+  GdkColorState *color_state;
   GdkTexture *texture;
 
   TIFFGetField (tif, TIFFTAG_IMAGEWIDTH, &width);
@@ -360,14 +413,18 @@ load_fallback (TIFF    *tif,
       return NULL;
     }
 
+  color_state = gdk_tiff_get_color_state (tif);
+
   bytes = g_bytes_new_take (data, width * height * 4);
 
-  texture = gdk_memory_texture_new (width, height,
-                                    GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
-                                    bytes,
-                                    width * 4);
+  texture = gdk_memory_texture_new_with_color_state (width, height,
+                                                     GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
+                                                     color_state,
+                                                     bytes,
+                                                     width * 4);
 
   g_bytes_unref (bytes);
+  gdk_color_state_unref (color_state);
 
   return texture;
 }
@@ -390,6 +447,7 @@ gdk_load_tiff (GBytes  *input_bytes,
   gsize stride;
   int bpp;
   GBytes *bytes;
+  GdkColorState *color_state;
   GdkTexture *texture;
   G_GNUC_UNUSED gint64 before = GDK_PROFILER_CURRENT_TIME;
 
@@ -490,13 +548,16 @@ gdk_load_tiff (GBytes  *input_bytes,
       line += stride;
     }
 
+  color_state = gdk_tiff_get_color_state (tif);
+
   bpp = gdk_memory_format_bytes_per_pixel (format);
   bytes = g_bytes_new_take (data, width * height * bpp);
 
-  texture = gdk_memory_texture_new (width, height,
-                                    format,
-                                    bytes, width * bpp);
+  texture = gdk_memory_texture_new_with_color_state (width, height,
+                                                     format, color_state,
+                                                     bytes, width * bpp);
   g_bytes_unref (bytes);
+  gdk_color_state_unref (color_state);
 
   TIFFClose (tif);
 

gdk/meson.build

@@ -6,6 +6,7 @@ gdk_public_sources = files([
   'gdkcairo.c',
   'gdkcairocontext.c',
   'gdkclipboard.c',
+  'gdkcolorstate.c',
   'gdkcontentdeserializer.c',
   'gdkcontentformats.c',
   'gdkcontentprovider.c',
@@ -75,6 +76,7 @@ gdk_public_headers = files([
   'gdkcairo.h',
   'gdkcairocontext.h',
   'gdkclipboard.h',
+  'gdkcolorstate.h',
   'gdkcontentdeserializer.h',
   'gdkcontentformats.h',
   'gdkcontentprovider.h',

gdk/x11/gdkglcontext-glx.c

@@ -24,6 +24,7 @@
 
 #include "gdkprofilerprivate.h"
 #include <glib/gi18n-lib.h>
+#include "gdksurfaceprivate.h"
 
 #include <cairo-xlib.h>
 
@@ -53,6 +54,9 @@ gdk_x11_surface_get_glx_drawable (GdkSurface *surface)
   GdkX11Surface *self = GDK_X11_SURFACE (surface);
   GdkDisplay *display = gdk_surface_get_display (GDK_SURFACE (self));
   GdkX11Display *display_x11 = GDK_X11_DISPLAY (display);
+  Display *dpy = gdk_x11_display_get_xdisplay (display);
+  XVisualInfo *visinfo;
+  int value;
 
   if (self->glx_drawable)
     return self->glx_drawable;
@@ -62,6 +66,11 @@ gdk_x11_surface_get_glx_drawable (GdkSurface *surface)
                                         gdk_x11_surface_get_xid (surface),
                                         NULL);
 
+  visinfo = glXGetVisualFromFBConfig (dpy, display_x11->glx_config);
+  glXGetConfig (dpy, visinfo, GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB, &value);
+  surface->is_srgb = value != 0;
+  XFree (visinfo);
+
   return self->glx_drawable;
 }
 
@@ -758,6 +767,17 @@ visual_is_rgba (XVisualInfo *visinfo)
     visinfo->visual->blue_mask  == 0x0000ff;
 }
 
+static gboolean
+visual_is_srgb (Display     *display,
+                XVisualInfo *visinfo)
+{
+  int value;
+
+  glXGetConfig (display, visinfo, GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB, &value);
+
+  return value != 0;
+}
+
 #define MAX_GLX_ATTRS   30
 
 static gboolean
@@ -777,6 +797,7 @@ gdk_x11_display_create_glx_config (GdkX11Display  *self,
     WITH_STENCIL_AND_DEPTH_BUFFER,
     NO_ALPHA,
     NO_ALPHA_VISUAL,
+    NO_SRGB,
     PERFECT
   } best_features;
   int i = 0;
@@ -865,6 +886,20 @@ gdk_x11_display_create_glx_config (GdkX11Display  *self,
           continue;
         }
 
+      if (!visual_is_srgb (dpy, visinfo))
+        {
+          if (best_features < NO_SRGB)
+            {
+              GDK_DISPLAY_DEBUG (display, OPENGL, "Best GLX config is %u for visual 0x%lX with no SRGB", i, visinfo->visualid);
+              best_features = NO_SRGB;
+              *out_visual = visinfo->visual;
+              *out_depth = visinfo->depth;
+              self->glx_config = configs[i];
+            }
+          XFree (visinfo);
+          continue;
+        }
+
       GDK_DISPLAY_DEBUG (display, OPENGL, "GLX config %u for visual 0x%lX is the perfect choice", i, visinfo->visualid);
       best_features = PERFECT;
       *out_visual = visinfo->visual;

gsk/gl/gskglcommandqueue.c

@@ -1483,6 +1483,7 @@ memory_format_gl_format (GskGLCommandQueue *self,
                          gboolean           ensure_mipmap,
                          gboolean          *out_can_mipmap,
                          GLint             *gl_internalformat,
+                         GLint             *gl_internalsrgbformat,
                          GLenum            *gl_format,
                          GLenum            *gl_type,
                          GLint              gl_swizzle[4])
@@ -1507,6 +1508,7 @@ memory_format_gl_format (GskGLCommandQueue *self,
       gdk_memory_format_gl_format (data_format,
                                    gdk_gl_context_get_use_es (self->context),
                                    gl_internalformat,
+                                   gl_internalsrgbformat,
                                    gl_format,
                                    gl_type,
                                    gl_swizzle);
@@ -1519,6 +1521,7 @@ memory_format_gl_format (GskGLCommandQueue *self,
                                         gdk_gl_context_get_use_es (self->context),
                                         &alt_format,
                                         gl_internalformat,
+                                        gl_internalsrgbformat,
                                         gl_format,
                                         gl_type,
                                         gl_swizzle))
@@ -1534,6 +1537,7 @@ memory_format_gl_format (GskGLCommandQueue *self,
           gdk_memory_format_gl_format (alt_format,
                                        gdk_gl_context_get_use_es (self->context),
                                        gl_internalformat,
+                                       gl_internalsrgbformat,
                                        gl_format,
                                        gl_type,
                                        gl_swizzle);
@@ -1552,6 +1556,7 @@ memory_format_gl_format (GskGLCommandQueue *self,
           gdk_memory_format_gl_format (fallbacks[i],
                                        gdk_gl_context_get_use_es (self->context),
                                        gl_internalformat,
+                                       gl_internalsrgbformat,
                                        gl_format,
                                        gl_type,
                                        gl_swizzle);
@@ -1670,7 +1675,7 @@ gsk_gl_command_queue_upload_texture_chunks (GskGLCommandQueue    *self,
   G_GNUC_UNUSED gint64 start_time = GDK_PROFILER_CURRENT_TIME;
   int width, height;
   GdkMemoryFormat data_format;
-  GLint gl_internalformat;
+  GLint gl_internalformat, gl_internalsrgbformat;
   GLenum gl_format;
   GLenum gl_type;
   GLint gl_swizzle[4];
@@ -1713,6 +1718,7 @@ gsk_gl_command_queue_upload_texture_chunks (GskGLCommandQueue    *self,
                                          ensure_mipmap,
                                          out_can_mipmap,
                                          &gl_internalformat,
+                                         &gl_internalsrgbformat,
                                          &gl_format,
                                          &gl_type,
                                          gl_swizzle);

gsk/gl/gskglglyphlibrary.c

@@ -30,6 +30,13 @@
 
 #include "gskdebugprivate.h"
 
+#ifdef HAVE_PANGOFT
+#include <pango/pangofc-font.h>
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_PARAMETER_TAGS_H
+#endif
+
 #define MAX_GLYPH_SIZE 128
 
 G_DEFINE_TYPE (GskGLGlyphLibrary, gsk_gl_glyph_library, GSK_TYPE_GL_TEXTURE_LIBRARY)
@@ -218,6 +225,16 @@ render_glyph (cairo_surface_t           *surface,
   cairo_t *cr;
   PangoGlyphString glyph_string;
   PangoGlyphInfo glyph_info;
+#ifdef HAVE_PANGOFT
+  FT_Face face;
+  FT_Bool darken = 1;
+  FT_Parameter property = { FT_PARAM_TAG_STEM_DARKENING, &darken };
+
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  face = pango_fc_font_lock_face (PANGO_FC_FONT (key->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+  FT_Face_Properties (face, 1, &property);
+#endif
 
   g_assert (surface != NULL);
 
@@ -236,6 +253,12 @@ render_glyph (cairo_surface_t           *surface,
   cairo_destroy (cr);
 
   cairo_surface_flush (surface);
+
+#ifdef HAVE_PANGOFT
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  pango_fc_font_unlock_face (PANGO_FC_FONT (key->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+#endif
 }
 
 static void

gsk/gl/gskglprograms.defs

@@ -102,3 +102,8 @@ GSK_GL_DEFINE_PROGRAM_NO_CLIP (external,
 GSK_GL_DEFINE_PROGRAM_NO_CLIP (premultiply,
                                GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("premultiply.glsl")),
                                GSK_GL_NO_UNIFORMS)
+
+GSK_GL_DEFINE_PROGRAM (colorconvert,
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("colorconvert.glsl")),
+                       GSK_GL_ADD_UNIFORM (1, TO_LINEAR, u_to_linear))
+

gsk/gl/gskglrenderer.c

@@ -34,6 +34,7 @@
 #include <gdk/gdkglcontextprivate.h>
 #include <gdk/gdksurfaceprivate.h>
 #include <gdk/gdksubsurfaceprivate.h>
+#include <gdk/gdkcolorstateprivate.h>
 #include <glib/gi18n-lib.h>
 #include <gsk/gskdebugprivate.h>
 #include <gsk/gskrendererprivate.h>
@@ -362,6 +363,7 @@ gsk_gl_renderer_render (GskRenderer          *renderer,
   GdkSurface *surface;
   gboolean clear_framebuffer;
   float scale;
+  GdkColorState *target_color_state;
 
   g_assert (GSK_IS_GL_RENDERER (renderer));
   g_assert (root != NULL);
@@ -384,6 +386,17 @@ gsk_gl_renderer_render (GskRenderer          *renderer,
                                      gsk_render_node_get_preferred_depth (root),
                                      update_area);
 
+  if (gdk_surface_get_gl_is_srgb (surface))
+    {
+      g_debug ("Relying on GL to do srgb-linear->srgb conversion");
+      target_color_state = GDK_COLOR_STATE_SRGB_LINEAR;
+    }
+  else
+    {
+      g_debug ("Using an offscreen for srgb-linear->srgb conversion");
+      target_color_state = GDK_COLOR_STATE_SRGB;
+    }
+
   gdk_gl_context_make_current (self->context);
 
   /* Must be called *AFTER* gdk_draw_context_begin_frame() */
@@ -392,7 +405,7 @@ gsk_gl_renderer_render (GskRenderer          *renderer,
 
   gsk_gl_driver_begin_frame (self->driver, self->command_queue);
   job = gsk_gl_render_job_new (self->driver, &viewport, scale, render_region, 0, clear_framebuffer);
-  gsk_gl_render_job_render (job, root);
+  gsk_gl_render_job_render (job, root, target_color_state);
   gsk_gl_driver_end_frame (self->driver);
   gsk_gl_render_job_free (job);
 
@@ -476,7 +489,7 @@ gsk_gl_renderer_render_texture (GskRenderer           *renderer,
     {
       gsk_gl_driver_begin_frame (self->driver, self->command_queue);
       job = gsk_gl_render_job_new (self->driver, viewport, 1, NULL, render_target->framebuffer_id, TRUE);
-      gsk_gl_render_job_render_flipped (job, root);
+      gsk_gl_render_job_render_flipped (job, root, GDK_COLOR_STATE_SRGB);
       texture_id = gsk_gl_driver_release_render_target (self->driver, render_target, FALSE);
       texture = gsk_gl_driver_create_gdk_texture (self->driver, texture_id, gdk_format);
       gsk_gl_driver_end_frame (self->driver);

gsk/gl/gskglrenderjob.c

@@ -33,6 +33,7 @@
 #include <gdk/gdkdmabuftexture.h>
 #include <gdk/gdksurfaceprivate.h>
 #include <gdk/gdksubsurfaceprivate.h>
+#include <gdk/gdkcolorstateprivate.h>
 #include <gsk/gsktransformprivate.h>
 #include <gsk/gskroundedrectprivate.h>
 #include <gsk/gskrectprivate.h>
@@ -972,11 +973,28 @@ gsk_gl_render_job_update_clip (GskGLRenderJob        *job,
   return TRUE;
 }
 
+
+static inline float
+srgb_inverse_transfer_function (float v)
+{
+  if (v >= 0.04045)
+    return powf (((v + 0.055)/(1 + 0.055)), 2.4);
+  else
+    return v / 12.92;
+}
+
 static inline void
 rgba_to_half (const GdkRGBA *rgba,
               guint16        h[4])
 {
-  float_to_half4 ((const float *)rgba, h);
+  float v[4];
+
+  v[0] = srgb_inverse_transfer_function (rgba->red);
+  v[1] = srgb_inverse_transfer_function (rgba->green);
+  v[2] = srgb_inverse_transfer_function (rgba->blue);
+  v[3] = rgba->alpha;
+
+  float_to_half4 (v, h);
 }
 
 /* fill_vertex_data */
@@ -3677,8 +3695,11 @@ gsk_gl_render_job_visit_texture (GskGLRenderJob        *job,
       g_assert (offscreen.texture_id);
       g_assert (offscreen.was_offscreen == FALSE);
 
-      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
         {
+          gsk_gl_program_set_uniform1i (job->current_program,
+                                        UNIFORM_TO_LINEAR, 0,
+                                        1);
           gsk_gl_program_set_uniform_texture_with_sync (job->current_program,
                                                         UNIFORM_SHARED_SOURCE, 0,
                                                         GL_TEXTURE_2D,
@@ -3704,7 +3725,7 @@ gsk_gl_render_job_visit_texture (GskGLRenderJob        *job,
       g_assert (slices != NULL);
       g_assert (n_slices > 0);
 
-      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
         {
           for (unsigned int i = 0; i < n_slices; i++)
             {
@@ -3718,6 +3739,9 @@ gsk_gl_render_job_visit_texture (GskGLRenderJob        *job,
 
               if (i > 0)
                 gsk_gl_render_job_split_draw (job);
+              gsk_gl_program_set_uniform1i (job->current_program,
+                                            UNIFORM_TO_LINEAR, 0,
+                                            1);
               gsk_gl_program_set_uniform_texture_with_filter (job->current_program,
                                                               UNIFORM_SHARED_SOURCE, 0,
                                                               GL_TEXTURE_2D,
@@ -3832,8 +3856,11 @@ gsk_gl_render_job_visit_texture_scale_node (GskGLRenderJob      *job,
       u1 = (clip_rect.origin.x + clip_rect.size.width - bounds->origin.x) / bounds->size.width;
       v1 = (clip_rect.origin.y + clip_rect.size.height - bounds->origin.y) / bounds->size.height;
 
-      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
         {
+          gsk_gl_program_set_uniform1i (job->current_program,
+                                        UNIFORM_TO_LINEAR, 0,
+                                        1);
           gsk_gl_program_set_uniform_texture_with_sync (job->current_program,
                                                         UNIFORM_SHARED_SOURCE, 0,
                                                         GL_TEXTURE_2D,
@@ -3859,7 +3886,7 @@ gsk_gl_render_job_visit_texture_scale_node (GskGLRenderJob      *job,
 
       gsk_gl_driver_slice_texture (job->driver, texture, need_mipmap, &slices, &n_slices);
 
-      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
         {
           for (guint i = 0; i < n_slices; i++)
             {
@@ -3877,6 +3904,9 @@ gsk_gl_render_job_visit_texture_scale_node (GskGLRenderJob      *job,
               if (i > 0)
                 gsk_gl_render_job_split_draw (job);
 
+              gsk_gl_program_set_uniform1i (job->current_program,
+                                            UNIFORM_TO_LINEAR, 0,
+                                            1);
               gsk_gl_program_set_uniform_texture_with_filter (job->current_program,
                                                               UNIFORM_SHARED_SOURCE, 0,
                                                               GL_TEXTURE_2D,
@@ -3910,8 +3940,11 @@ gsk_gl_render_job_visit_texture_scale_node (GskGLRenderJob      *job,
   gsk_gl_driver_cache_texture (job->driver, &key, texture_id);
 
 render_texture:
-  if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+  if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
     {
+      gsk_gl_program_set_uniform1i (job->current_program,
+                                    UNIFORM_TO_LINEAR, 0,
+                                    1);
       gsk_gl_program_set_uniform_texture (job->current_program,
                                           UNIFORM_SHARED_SOURCE, 0,
                                           GL_TEXTURE_2D,
@@ -4464,7 +4497,8 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
 
 void
 gsk_gl_render_job_render_flipped (GskGLRenderJob *job,
-                                  GskRenderNode  *root)
+                                  GskRenderNode  *root,
+                                  GdkColorState  *target_color_state)
 {
   graphene_matrix_t proj;
   guint framebuffer_id;
@@ -4506,8 +4540,17 @@ gsk_gl_render_job_render_flipped (GskGLRenderJob *job,
   gsk_gl_render_job_set_alpha (job, 1.0f);
   gsk_gl_command_queue_bind_framebuffer (job->command_queue, job->framebuffer);
   gsk_gl_command_queue_clear (job->command_queue, 0, &job->viewport);
-  if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, blit)))
+
+  GskGLProgram *program;
+  if (target_color_state == GDK_COLOR_STATE_SRGB)
+    program = CHOOSE_PROGRAM (job, colorconvert);
+  else
+    program = CHOOSE_PROGRAM (job, blit);
+
+  if (gsk_gl_render_job_begin_draw (job, program))
     {
+      if (target_color_state == GDK_COLOR_STATE_SRGB)
+        gsk_gl_program_set_uniform1i (job->current_program, UNIFORM_TO_LINEAR, 0, 0);
       gsk_gl_program_set_uniform_texture (job->current_program,
                                           UNIFORM_SHARED_SOURCE, 0,
                                           GL_TEXTURE_2D,
@@ -4528,7 +4571,8 @@ gsk_gl_render_job_render_flipped (GskGLRenderJob *job,
 
 void
 gsk_gl_render_job_render (GskGLRenderJob *job,
-                          GskRenderNode  *root)
+                          GskRenderNode  *root,
+                          GdkColorState  *target_color_state)
 {
   G_GNUC_UNUSED gint64 start_time;
   float scale;
@@ -4551,7 +4595,38 @@ gsk_gl_render_job_render (GskGLRenderJob *job,
   gsk_gl_command_queue_bind_framebuffer (job->command_queue, job->framebuffer);
   if (job->clear_framebuffer)
     gsk_gl_command_queue_clear (job->command_queue, 0, &job->viewport);
-  gsk_gl_render_job_visit_node (job, root);
+
+  if (target_color_state == GDK_COLOR_STATE_SRGB_LINEAR)
+    {
+      gsk_gl_render_job_visit_node (job, root);
+    }
+  else
+    {
+      GskGLRenderOffscreen offscreen = {0};
+
+      offscreen.bounds = &root->bounds;
+      offscreen.force_offscreen = TRUE;
+      offscreen.reset_clip = TRUE;
+      offscreen.do_not_cache = TRUE;
+
+      gsk_gl_render_job_visit_node_with_offscreen (job, root, &offscreen);
+
+      g_assert (offscreen.texture_id);
+
+      if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, colorconvert)))
+        {
+          gsk_gl_program_set_uniform1i (job->current_program, UNIFORM_TO_LINEAR, 0, 0);
+          gsk_gl_program_set_uniform_texture (job->current_program,
+                                              UNIFORM_SHARED_SOURCE, 0,
+                                              GL_TEXTURE_2D,
+                                              GL_TEXTURE0,
+                                              offscreen.texture_id);
+          job->source_is_glyph_atlas = FALSE;
+          gsk_gl_render_job_draw_offscreen_rect (job, &root->bounds);
+          gsk_gl_render_job_end_draw (job);
+        }
+    }
+
   gdk_gl_context_pop_debug_group (job->command_queue->context);
 
   gdk_profiler_end_mark (start_time, "Build GL command queue", "");

gsk/gl/gskglrenderjobprivate.h

@@ -30,7 +30,9 @@ GskGLRenderJob *gsk_gl_render_job_new                (GskGLDriver           *dri
                                                       gboolean               clear_framebuffer);
 void            gsk_gl_render_job_free               (GskGLRenderJob        *job);
 void            gsk_gl_render_job_render             (GskGLRenderJob        *job,
-                                                      GskRenderNode         *root);
+                                                      GskRenderNode         *root,
+                                                      GdkColorState         *color_state);
 void            gsk_gl_render_job_render_flipped     (GskGLRenderJob        *job,
-                                                      GskRenderNode         *root);
+                                                      GskRenderNode         *root,
+                                                      GdkColorState         *color_state);
 

gsk/gl/resources/colorconvert.glsl

@@ -0,0 +1,63 @@
+// VERTEX_SHADER:
+// colorconvert.glsl
+
+void main() {
+  gl_Position = u_projection * u_modelview * vec4(aPosition, 0.0, 1.0);
+
+  vUv = vec2(aUv.x, aUv.y);
+}
+
+// FRAGMENT_SHADER:
+// colorconvert.glsl
+
+uniform int u_to_linear;
+
+float
+srgb_transfer_function (float v)
+{
+  if (v >= 0.04045)
+    return pow (((v + 0.055)/(1.0 + 0.055)), 2.4);
+  else
+    return v / 12.92;
+}
+
+float
+srgb_inverse_transfer_function (float v)
+{
+  if (v > 0.0031308)
+    return 1.055 * pow (v, 1.0/2.4) - 0.055;
+  else
+    return 12.92 * v;
+}
+
+vec4
+srgb_to_linear_srgb (vec4 color)
+{
+  return vec4 (srgb_transfer_function (color.r),
+               srgb_transfer_function (color.g),
+               srgb_transfer_function (color.b),
+               color.a);
+}
+
+vec4
+linear_srgb_to_srgb (vec4 color)
+{
+  return vec4 (srgb_inverse_transfer_function (color.r),
+               srgb_inverse_transfer_function (color.g),
+               srgb_inverse_transfer_function (color.b),
+               color.a);
+}
+
+void main() {
+  vec4 color = GskTexture(u_source, vUv);
+
+  if (color.a != 0.0)
+    color.rgb /= color.a;
+
+  if (u_to_linear != 0)
+    color = srgb_to_linear_srgb (color);
+  else
+    color = linear_srgb_to_srgb (color);
+
+  gskSetOutputColor(gsk_scaled_premultiply(color, u_alpha));
+}

gsk/gpu/gskgldevice.c

@@ -10,6 +10,7 @@
 #include "gdk/gdkdisplayprivate.h"
 #include "gdk/gdkglcontextprivate.h"
 #include "gdk/gdkprofilerprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #include <glib/gi18n-lib.h>
 
@@ -76,6 +77,7 @@ gsk_gl_device_create_offscreen_image (GskGpuDevice   *device,
 
   return gsk_gl_image_new (self,
                            gdk_memory_depth_get_format (depth),
+                           GDK_COLOR_STATE_SRGB_LINEAR,
                            GSK_GPU_IMAGE_RENDERABLE | GSK_GPU_IMAGE_FILTERABLE,
                            width,
                            height);
@@ -85,6 +87,7 @@ static GskGpuImage *
 gsk_gl_device_create_upload_image (GskGpuDevice    *device,
                                    gboolean         with_mipmap,
                                    GdkMemoryFormat  format,
+                                   GdkColorState   *color_state,
                                    gsize            width,
                                    gsize            height)
 {
@@ -92,6 +95,7 @@ gsk_gl_device_create_upload_image (GskGpuDevice    *device,
 
   return gsk_gl_image_new (self,
                            format,
+                           color_state,
                            0,
                            width,
                            height);
@@ -107,6 +111,7 @@ gsk_gl_device_create_download_image (GskGpuDevice   *device,
 
   return gsk_gl_image_new (self,
                            gdk_memory_depth_get_format (depth),
+                           GDK_COLOR_STATE_SRGB_LINEAR,
                            GSK_GPU_IMAGE_RENDERABLE,
                            width,
                            height);
@@ -121,6 +126,7 @@ gsk_gl_device_create_atlas_image (GskGpuDevice *device,
 
   return gsk_gl_image_new (self,
                            GDK_MEMORY_DEFAULT,
+                           GDK_COLOR_STATE_SRGB_LINEAR,
                            GSK_GPU_IMAGE_RENDERABLE,
                            width,
                            height);
@@ -635,6 +641,7 @@ gsk_gl_device_find_gl_format (GskGLDevice      *self,
                               GdkMemoryFormat  *out_format,
                               GskGpuImageFlags *out_flags,
                               GLint            *out_gl_internal_format,
+                              GLint            *out_gl_internal_srgb_format,
                               GLenum           *out_gl_format,
                               GLenum           *out_gl_type,
                               GLint             out_swizzle[4])
@@ -654,6 +661,7 @@ gsk_gl_device_find_gl_format (GskGLDevice      *self,
       gdk_memory_format_gl_format (format,
                                    gdk_gl_context_get_use_es (context),
                                    out_gl_internal_format,
+                                   out_gl_internal_srgb_format,
                                    out_gl_format,
                                    out_gl_type,
                                    out_swizzle);
@@ -665,6 +673,7 @@ gsk_gl_device_find_gl_format (GskGLDevice      *self,
                                         gdk_gl_context_get_use_es (context),
                                         &alt_format,
                                         out_gl_internal_format,
+                                        out_gl_internal_srgb_format,
                                         out_gl_format,
                                         out_gl_type,
                                         out_swizzle) &&
@@ -688,6 +697,7 @@ gsk_gl_device_find_gl_format (GskGLDevice      *self,
           gdk_memory_format_gl_format (fallbacks[i],
                                        gdk_gl_context_get_use_es (context),
                                        out_gl_internal_format,
+                                       out_gl_internal_srgb_format,
                                        out_gl_format,
                                        out_gl_type,
                                        out_swizzle);

gsk/gpu/gskgldeviceprivate.h

@@ -26,6 +26,7 @@ void                    gsk_gl_device_find_gl_format                    (GskGLDe
                                                                          GdkMemoryFormat        *out_format,
                                                                          GskGpuImageFlags       *out_flags,
                                                                          GLint                  *out_gl_internal_format,
+                                                                         GLint                  *out_gl_internal_srgb_format,
                                                                          GLenum                 *out_gl_format,
                                                                          GLenum                 *out_gl_type,
                                                                          GLint                   out_swizzle[4]);

gsk/gpu/gskglimage.c

@@ -1,9 +1,10 @@
-#include "config.h"
+        #include "config.h"
 
 #include "gskglimageprivate.h"
 
 #include "gdk/gdkdisplayprivate.h"
 #include "gdk/gdkglcontextprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 struct _GskGLImage
 {
@@ -73,11 +74,13 @@ gsk_gl_image_new_backbuffer (GskGLDevice    *device,
                              GdkGLContext   *context,
                              GdkMemoryFormat format,
                              gsize           width,
-                             gsize           height)
+                             gsize           height,
+                             gboolean        is_srgb)
 {
   GskGLImage *self;
   GskGpuImageFlags flags;
   GLint swizzle[4];
+  GLint gl_internal_format, gl_internal_srgb_format;
 
   self = g_object_new (GSK_TYPE_GL_IMAGE, NULL);
 
@@ -87,11 +90,25 @@ gsk_gl_image_new_backbuffer (GskGLDevice    *device,
                                 0,
                                 &format,
                                 &flags,
-                                &self->gl_internal_format,
+                                &gl_internal_format,
+                                &gl_internal_srgb_format,
                                 &self->gl_format,
                                 &self->gl_type,
                                 swizzle);
-  
+
+  if (is_srgb)
+    {
+      if (gl_internal_srgb_format != -1)
+        self->gl_internal_format = gl_internal_srgb_format;
+      else /* FIXME: not really correct */
+        self->gl_internal_format = gl_internal_format;
+      flags |= GSK_GPU_IMAGE_SRGB;
+    }
+  else
+    {
+      self->gl_internal_format = gl_internal_format;
+    }
+
   gsk_gpu_image_setup (GSK_GPU_IMAGE (self), flags, format, width, height);
 
   /* texture_id == 0 means backbuffer */
@@ -109,6 +126,7 @@ gsk_gl_image_new_backbuffer (GskGLDevice    *device,
 GskGpuImage *
 gsk_gl_image_new (GskGLDevice      *device,
                   GdkMemoryFormat   format,
+                  GdkColorState    *color_state,
                   GskGpuImageFlags  required_flags,
                   gsize             width,
                   gsize             height)
@@ -116,6 +134,7 @@ gsk_gl_image_new (GskGLDevice      *device,
   GskGLImage *self;
   GLint swizzle[4];
   GskGpuImageFlags flags;
+  GLint gl_internal_format, gl_internal_srgb_format;
   gsize max_size;
 
   max_size = gsk_gpu_device_get_max_image_size (GSK_GPU_DEVICE (device));
@@ -129,11 +148,23 @@ gsk_gl_image_new (GskGLDevice      *device,
                                 required_flags,
                                 &format,
                                 &flags,
-                                &self->gl_internal_format,
+                                &gl_internal_format,
+                                &gl_internal_srgb_format,
                                 &self->gl_format,
                                 &self->gl_type,
                                 swizzle);
-  
+
+  if (gl_internal_srgb_format != -1 &&
+      gdk_color_state_equal (color_state, GDK_COLOR_STATE_SRGB))
+    {
+      self->gl_internal_format = gl_internal_srgb_format;
+      flags |= GSK_GPU_IMAGE_SRGB;
+    }
+  else
+    {
+      self->gl_internal_format = gl_internal_format;
+    }
+
   gsk_gpu_image_setup (GSK_GPU_IMAGE (self),
                        flags,
                        format,
@@ -177,6 +208,7 @@ gsk_gl_image_new_for_texture (GskGLDevice      *device,
   GdkMemoryFormat format, real_format;
   GskGpuImageFlags flags;
   GskGLImage *self;
+  GLint gl_internal_format, gl_internal_srgb_format;
   GLint swizzle[4];
 
   format = gdk_texture_get_format (owner);
@@ -188,10 +220,14 @@ gsk_gl_image_new_for_texture (GskGLDevice      *device,
                                 0,
                                 &real_format,
                                 &flags,
-                                &self->gl_internal_format,
+                                &gl_internal_format,
+                                &gl_internal_srgb_format,
                                 &self->gl_format,
                                 &self->gl_type,
                                 swizzle);
+  
+  self->gl_internal_format = gl_internal_format;
+
   if (format != real_format)
     flags = GSK_GPU_IMAGE_NO_BLIT | 
             (gdk_memory_format_alpha (format) == GDK_MEMORY_ALPHA_STRAIGHT ? GSK_GPU_IMAGE_STRAIGHT_ALPHA : 0);

gsk/gpu/gskglimageprivate.h

@@ -14,9 +14,11 @@ GskGpuImage *           gsk_gl_image_new_backbuffer                     (GskGLDe
                                                                          GdkGLContext           *context,
                                                                          GdkMemoryFormat         format,
                                                                          gsize                   width,
-                                                                         gsize                   height);
+                                                                         gsize                   height,
+                                                                         gboolean                converts_srgb);
 GskGpuImage *           gsk_gl_image_new                                (GskGLDevice            *device,
                                                                          GdkMemoryFormat         format,
+                                                                         GdkColorState          *color_state,
                                                                          GskGpuImageFlags        required_flags,
                                                                          gsize                   width,
                                                                          gsize                   height);

gsk/gpu/gskgpuclearop.c

@@ -14,7 +14,7 @@ struct _GskGpuClearOp
   GskGpuOp op;
 
   cairo_rectangle_int_t rect;
-  GdkRGBA color;
+  float color[4];
 };
 
 static void
@@ -29,23 +29,14 @@ gsk_gpu_clear_op_print (GskGpuOp    *op,
                         guint        indent)
 {
   GskGpuClearOp *self = (GskGpuClearOp *) op;
-  float rgba[4];
 
   gsk_gpu_print_op (string, indent, "clear");
   gsk_gpu_print_int_rect (string, &self->rect);
-  gsk_gpu_rgba_to_float (&self->color, rgba);
-  gsk_gpu_print_rgba (string, rgba);
+  gsk_gpu_print_rgba (string, self->color);
   gsk_gpu_print_newline (string);
 }
 
 #ifdef GDK_RENDERING_VULKAN
-static void
-gsk_gpu_init_clear_value (VkClearValue  *value,
-                          const GdkRGBA *rgba)
-{
-  gsk_gpu_rgba_to_float (rgba, value->color.float32);
-}
-
 static GskGpuOp *
 gsk_gpu_clear_op_vk_command (GskGpuOp              *op,
                              GskGpuFrame           *frame,
@@ -54,7 +45,7 @@ gsk_gpu_clear_op_vk_command (GskGpuOp              *op,
   GskGpuClearOp *self = (GskGpuClearOp *) op;
   VkClearValue clear_value;
 
-  gsk_gpu_init_clear_value (&clear_value, &self->color);
+  memcpy (clear_value.color.float32, self->color, sizeof (float) * 4);
 
   vkCmdClearAttachments (state->vk_command_buffer,
                          1,
@@ -92,7 +83,7 @@ gsk_gpu_clear_op_gl_command (GskGpuOp          *op,
   else
     glScissor (self->rect.x, self->rect.y, self->rect.width, self->rect.height);
 
-  glClearColor (self->color.red, self->color.green, self->color.blue, self->color.alpha);
+  glClearColor (self->color[0], self->color[1], self->color[2], self->color[3]);
   glClear (GL_COLOR_BUFFER_BIT);
 
   glScissor (scissor[0], scissor[1], scissor[2], scissor[3]);
@@ -121,5 +112,5 @@ gsk_gpu_clear_op (GskGpuFrame                 *frame,
   self = (GskGpuClearOp *) gsk_gpu_op_alloc (frame, &GSK_GPU_CLEAR_OP_CLASS);
 
   self->rect = *rect;
-  self->color = *color;
+  gsk_gpu_rgba_to_float (color, self->color);
 }

gsk/gpu/gskgpucolorconvertop.c

@@ -0,0 +1,86 @@
+#include "config.h"
+
+#include "gskgpucolorconvertopprivate.h"
+
+#include "gskgpuframeprivate.h"
+#include "gskgpuprintprivate.h"
+#include "gskrectprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
+
+#include "gpu/shaders/gskgpucolorconvertinstance.h"
+
+typedef struct _GskGpuColorConvertOp GskGpuColorConvertOp;
+
+struct _GskGpuColorConvertOp
+{
+  GskGpuShaderOp op;
+};
+
+static guint
+gsk_gpu_color_conversion (GdkColorState *from,
+                          GdkColorState *to)
+{
+  if (from == to)
+    return 0;
+
+  return GDK_DEFAULT_COLOR_STATE_ID (from) | (GDK_DEFAULT_COLOR_STATE_ID (to) << 16);
+}
+
+static void
+gsk_gpu_color_convert_op_print_instance (GskGpuShaderOp *shader,
+                                         gpointer        instance_,
+                                         GString        *string)
+{
+  GskGpuColorconvertInstance *instance = (GskGpuColorconvertInstance *) instance_;
+
+  gsk_gpu_print_rect (string, instance->rect);
+  gsk_gpu_print_image_descriptor (string, shader->desc, instance->tex_id);
+  gsk_gpu_print_color_conversion (string, shader->variation);
+}
+
+static const GskGpuShaderOpClass GSK_GPU_COLOR_CONVERT_OP_CLASS = {
+  {
+    GSK_GPU_OP_SIZE (GskGpuColorConvertOp),
+    GSK_GPU_STAGE_SHADER,
+    gsk_gpu_shader_op_finish,
+    gsk_gpu_shader_op_print,
+#ifdef GDK_RENDERING_VULKAN
+    gsk_gpu_shader_op_vk_command,
+#endif
+    gsk_gpu_shader_op_gl_command
+  },
+  "gskgpucolorconvert",
+  sizeof (GskGpuColorconvertInstance),
+#ifdef GDK_RENDERING_VULKAN
+  &gsk_gpu_colorconvert_info,
+#endif
+  gsk_gpu_color_convert_op_print_instance,
+  gsk_gpu_colorconvert_setup_attrib_locations,
+  gsk_gpu_colorconvert_setup_vao
+};
+
+void
+gsk_gpu_color_convert_op (GskGpuFrame            *frame,
+                          GskGpuShaderClip        clip,
+                          GdkColorState          *from,
+                          GdkColorState          *to,
+                          GskGpuDescriptors      *desc,
+                          guint32                 descriptor,
+                          const graphene_rect_t  *rect,
+                          const graphene_point_t *offset,
+                          const graphene_rect_t  *tex_rect)
+{
+  GskGpuColorconvertInstance *instance;
+
+  gsk_gpu_shader_op_alloc (frame,
+                           &GSK_GPU_COLOR_CONVERT_OP_CLASS,
+                           gsk_gpu_color_conversion (from, to),
+                           clip,
+                           desc,
+                           &instance);
+
+  gsk_gpu_rect_to_float (rect, offset, instance->rect);
+  gsk_gpu_rect_to_float (tex_rect, offset, instance->tex_rect);
+  instance->tex_id = descriptor;
+}
+

gsk/gpu/gskgpucolorconvertopprivate.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include "gskgpushaderopprivate.h"
+
+#include <graphene.h>
+
+G_BEGIN_DECLS
+
+void                    gsk_gpu_color_convert_op                        (GskGpuFrame                    *frame,
+                                                                         GskGpuShaderClip                clip,
+                                                                         GdkColorState                  *from,
+                                                                         GdkColorState                  *to,
+                                                                         GskGpuDescriptors              *desc,
+                                                                         guint32                         descriptor,
+                                                                         const graphene_rect_t          *rect,
+                                                                         const graphene_point_t         *offset,
+                                                                         const graphene_rect_t          *tex_rect);
+
+
+G_END_DECLS
+

gsk/gpu/gskgpudevice.c

@@ -12,6 +12,7 @@
 
 #include "gsk/gskdebugprivate.h"
 #include "gsk/gskprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #define MAX_SLICES_PER_ATLAS 64
 
@@ -252,6 +253,9 @@ struct _GskGpuCachedTexture
 
   GdkTexture *texture;
   GskGpuImage *image;
+  GdkColorState *color_state;
+  GskGpuImage *image2;
+  GdkColorState *color_state2;
 };
 
 static void
@@ -263,6 +267,9 @@ gsk_gpu_cached_texture_free (GskGpuDevice *device,
   gpointer key, value;
 
   g_clear_object (&self->image);
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
+  g_clear_object (&self->image2);
+  g_clear_pointer (&self->color_state2, gdk_color_state_unref);
 
   if (g_hash_table_steal_extended (priv->texture_cache, self->texture, &key, &value))
     {
@@ -325,9 +332,10 @@ gsk_gpu_cached_texture_destroy_cb (gpointer data)
 }
 
 static GskGpuCachedTexture *
-gsk_gpu_cached_texture_new (GskGpuDevice *device,
-                            GdkTexture   *texture,
-                            GskGpuImage  *image)
+gsk_gpu_cached_texture_new (GskGpuDevice  *device,
+                            GdkTexture    *texture,
+                            GskGpuImage   *image,
+                            GdkColorState *color_state)
 {
   GskGpuDevicePrivate *priv = gsk_gpu_device_get_instance_private (device);
   GskGpuCachedTexture *self;
@@ -340,6 +348,9 @@ gsk_gpu_cached_texture_new (GskGpuDevice *device,
   self = gsk_gpu_cached_new (device, &GSK_GPU_CACHED_TEXTURE_CLASS, NULL);
   self->texture = texture;
   self->image = g_object_ref (image);
+  self->color_state = gdk_color_state_ref (color_state);
+  self->image2 = NULL;
+  self->color_state2 = NULL;
   ((GskGpuCached *)self)->pixels = gsk_gpu_image_get_width (image) * gsk_gpu_image_get_height (image);
   self->dead_pixels_counter = &priv->dead_texture_pixels;
   self->use_count = 2;
@@ -696,13 +707,14 @@ gsk_gpu_device_create_offscreen_image (GskGpuDevice   *self,
 }
 
 GskGpuImage *
-gsk_gpu_device_create_upload_image (GskGpuDevice   *self,
-                                    gboolean        with_mipmap,
-                                    GdkMemoryFormat format,
-                                    gsize           width,
-                                    gsize           height)
+gsk_gpu_device_create_upload_image (GskGpuDevice    *self,
+                                    gboolean         with_mipmap,
+                                    GdkMemoryFormat  format,
+                                    GdkColorState   *color_state,
+                                    gsize            width,
+                                    gsize            height)
 {
-  return GSK_GPU_DEVICE_GET_CLASS (self)->create_upload_image (self, with_mipmap, format, width, height);
+  return GSK_GPU_DEVICE_GET_CLASS (self)->create_upload_image (self, with_mipmap, format, color_state, width, height);
 }
 
 void
@@ -850,34 +862,65 @@ gsk_gpu_device_add_atlas_image (GskGpuDevice      *self,
 }
 
 GskGpuImage *
-gsk_gpu_device_lookup_texture_image (GskGpuDevice *self,
-                                     GdkTexture   *texture,
-                                     gint64        timestamp)
+gsk_gpu_device_lookup_texture_image (GskGpuDevice   *self,
+                                     GdkTexture     *texture,
+                                     GdkColorState  *color_state,
+                                     gint64          timestamp)
 {
   GskGpuDevicePrivate *priv = gsk_gpu_device_get_instance_private (self);
   GskGpuCachedTexture *cache;
+  GskGpuImage *image;
 
   cache = gdk_texture_get_render_data (texture, self);
   if (cache == NULL)
     cache = g_hash_table_lookup (priv->texture_cache, texture);
 
-  if (!cache || !cache->image || gsk_gpu_cached_texture_is_invalid (cache))
+  if (!cache || gsk_gpu_cached_texture_is_invalid (cache))
+    return NULL;
+
+  if (gdk_color_state_equal (color_state, cache->color_state))
+    image = cache->image;
+  else if (cache->color_state2 && gdk_color_state_equal (color_state, cache->color_state2))
+    image = cache->image2;
+  else
     return NULL;
 
   gsk_gpu_cached_use (self, (GskGpuCached *) cache, timestamp);
 
-  return g_object_ref (cache->image);
+  return g_object_ref (image);
 }
 
 void
-gsk_gpu_device_cache_texture_image (GskGpuDevice *self,
-                                    GdkTexture   *texture,
-                                    gint64        timestamp,
-                                    GskGpuImage  *image)
+gsk_gpu_device_cache_texture_image (GskGpuDevice  *self,
+                                    GdkTexture    *texture,
+                                    gint64         timestamp,
+                                    GskGpuImage   *image,
+                                    GdkColorState *color_state)
 {
   GskGpuCachedTexture *cache;
 
-  cache = gsk_gpu_cached_texture_new (self, texture, image);
+  cache = gdk_texture_get_render_data (texture, self);
+  if (cache)
+    {
+      if (gdk_color_state_equal (color_state, gdk_texture_get_color_state (texture)))
+        {
+          g_clear_pointer (&cache->color_state, gdk_color_state_unref);
+          g_clear_object (&cache->image);
+          cache->color_state = gdk_color_state_ref (color_state);
+          cache->image = g_object_ref (image);
+        }
+      else
+        {
+          g_clear_pointer (&cache->color_state2, gdk_color_state_unref);
+          g_clear_object (&cache->image2);
+          cache->color_state2 = gdk_color_state_ref (color_state);
+          cache->image2 = g_object_ref (image);
+        }
+    }
+  else
+    {
+      cache = gsk_gpu_cached_texture_new (self, texture, image, color_state);
+    }
 
   gsk_gpu_cached_use (self, (GskGpuCached *) cache, timestamp);
 }
@@ -950,7 +993,7 @@ gsk_gpu_device_lookup_glyph_image (GskGpuDevice           *self,
     }
   else
     {
-      image = gsk_gpu_device_create_upload_image (self, FALSE, GDK_MEMORY_DEFAULT, rect.size.width, rect.size.height),
+      image = gsk_gpu_device_create_upload_image (self, FALSE, GDK_MEMORY_DEFAULT, GDK_COLOR_STATE_SRGB, rect.size.width, rect.size.height),
       rect.origin.x = 0;
       rect.origin.y = 0;
       padding = 0;

gsk/gpu/gskgpudeviceprivate.h

@@ -35,6 +35,7 @@ struct _GskGpuDeviceClass
   GskGpuImage *         (* create_upload_image)                         (GskGpuDevice           *self,
                                                                          gboolean                with_mipmap,
                                                                          GdkMemoryFormat         format,
+                                                                         GdkColorState          *color_state,
                                                                          gsize                   width,
                                                                          gsize                   height);
   GskGpuImage *         (* create_download_image)                       (GskGpuDevice           *self,
@@ -64,6 +65,7 @@ GskGpuImage *           gsk_gpu_device_create_offscreen_image           (GskGpuD
 GskGpuImage *           gsk_gpu_device_create_upload_image              (GskGpuDevice           *self,
                                                                          gboolean                with_mipmap,
                                                                          GdkMemoryFormat         format,
+                                                                         GdkColorState          *color_state,
                                                                          gsize                   width,
                                                                          gsize                   height);
 GskGpuImage *           gsk_gpu_device_create_download_image            (GskGpuDevice           *self,
@@ -73,11 +75,13 @@ GskGpuImage *           gsk_gpu_device_create_download_image            (GskGpuD
 void                    gsk_gpu_device_make_current                     (GskGpuDevice           *self);
 GskGpuImage *           gsk_gpu_device_lookup_texture_image             (GskGpuDevice           *self,
                                                                          GdkTexture             *texture,
+                                                                         GdkColorState          *color_state,
                                                                          gint64                  timestamp);
 void                    gsk_gpu_device_cache_texture_image              (GskGpuDevice           *self,
                                                                          GdkTexture             *texture,
                                                                          gint64                  timestamp,
-                                                                         GskGpuImage            *image);
+                                                                         GskGpuImage            *image,
+                                                                         GdkColorState          *color_state);
 
 typedef enum
 {

gsk/gpu/gskgpudownloadop.c

@@ -146,7 +146,7 @@ gsk_gpu_download_op_vk_command (GskGpuOp              *op,
       GskVulkanDevice *device = GSK_VULKAN_DEVICE (gsk_gpu_frame_get_device (frame));
       VkDevice vk_device = gsk_vulkan_device_get_vk_device (device);
 
-      gsk_gpu_device_cache_texture_image (GSK_GPU_DEVICE (device), self->texture, gsk_gpu_frame_get_timestamp (frame), self->image);
+      gsk_gpu_device_cache_texture_image (GSK_GPU_DEVICE (device), self->texture, gsk_gpu_frame_get_timestamp (frame), self->image, gdk_texture_get_color_state (self->texture));
 
       if (gsk_vulkan_device_has_feature (device, GDK_VULKAN_FEATURE_SEMAPHORE_EXPORT))
         {

gsk/gpu/gskgpuframe.c

@@ -17,6 +17,7 @@
 
 #include "gdk/gdkdmabufdownloaderprivate.h"
 #include "gdk/gdktexturedownloaderprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #define DEFAULT_VERTEX_BUFFER_SIZE 128 * 1024
 
@@ -402,17 +403,26 @@ gsk_gpu_frame_get_last_op (GskGpuFrame *self)
 }
 
 GskGpuImage *
-gsk_gpu_frame_upload_texture (GskGpuFrame  *self,
-                              gboolean      with_mipmap,
-                              GdkTexture   *texture)
+gsk_gpu_frame_upload_texture (GskGpuFrame    *self,
+                              gboolean        with_mipmap,
+                              GdkTexture     *texture,
+                              GdkColorState **out_color_state)
 {
   GskGpuFramePrivate *priv = gsk_gpu_frame_get_instance_private (self);
   GskGpuImage *image;
+  GdkColorState *color_state;
 
   image = GSK_GPU_FRAME_GET_CLASS (self)->upload_texture (self, with_mipmap, texture);
 
+  if (gsk_gpu_image_get_flags (image) & GSK_GPU_IMAGE_SRGB)
+    color_state = GDK_COLOR_STATE_SRGB_LINEAR;
+  else
+    color_state = gdk_texture_get_color_state (texture);
+
   if (image)
-    gsk_gpu_device_cache_texture_image (priv->device, texture, priv->timestamp, image);
+    gsk_gpu_device_cache_texture_image (priv->device, texture, priv->timestamp, image, color_state);
+
+  *out_color_state = color_state;
 
   return image;
 }
@@ -561,6 +571,7 @@ copy_texture (gpointer    user_data,
 static void
 gsk_gpu_frame_record_rect (GskGpuFrame                 *self,
                            GskGpuImage                 *target,
+                           GdkColorState               *target_color_state,
                            const cairo_rectangle_int_t *clip,
                            GskRenderNode               *node,
                            const graphene_rect_t       *viewport)
@@ -572,6 +583,7 @@ gsk_gpu_frame_record_rect (GskGpuFrame                 *self,
 
   gsk_gpu_node_processor_process (self,
                                   target,
+                                  target_color_state,
                                   clip,
                                   node,
                                   viewport);
@@ -585,6 +597,7 @@ static void
 gsk_gpu_frame_record (GskGpuFrame            *self,
                       gint64                  timestamp,
                       GskGpuImage            *target,
+                      GdkColorState          *target_color_state,
                       const cairo_region_t   *clip,
                       GskRenderNode          *node,
                       const graphene_rect_t  *viewport,
@@ -603,13 +616,14 @@ gsk_gpu_frame_record (GskGpuFrame            *self,
           cairo_rectangle_int_t rect;
 
           cairo_region_get_rectangle (clip, i, &rect);
-          gsk_gpu_frame_record_rect (self, target, &rect, node, viewport);
+          gsk_gpu_frame_record_rect (self, target, target_color_state, &rect, node, viewport);
         }
     }
   else
     {
       gsk_gpu_frame_record_rect (self,
                                  target,
+                                 target_color_state,
                                  &(cairo_rectangle_int_t) {
                                      0, 0,
                                      gsk_gpu_image_get_width (target),
@@ -656,6 +670,7 @@ void
 gsk_gpu_frame_render (GskGpuFrame            *self,
                       gint64                  timestamp,
                       GskGpuImage            *target,
+                      GdkColorState          *target_color_state,
                       const cairo_region_t   *region,
                       GskRenderNode          *node,
                       const graphene_rect_t  *viewport,
@@ -663,7 +678,7 @@ gsk_gpu_frame_render (GskGpuFrame            *self,
 {
   gsk_gpu_frame_cleanup (self);
 
-  gsk_gpu_frame_record (self, timestamp, target, region, node, viewport, texture);
+  gsk_gpu_frame_record (self, timestamp, target, target_color_state, region, node, viewport, texture);
 
   gsk_gpu_frame_submit (self);
 }
@@ -702,10 +717,11 @@ gsk_gpu_frame_download_texture (GskGpuFrame     *self,
 {
   GskGpuFramePrivate *priv = gsk_gpu_frame_get_instance_private (self);
   GskGpuImage *image;
+  GdkColorState *color_state;
 
-  image = gsk_gpu_device_lookup_texture_image (priv->device, texture, timestamp);
+  image = gsk_gpu_device_lookup_texture_image (priv->device, texture, GDK_COLOR_STATE_SRGB, timestamp);
   if (image == NULL)
-    image = gsk_gpu_frame_upload_texture (self, FALSE, texture);
+    image = gsk_gpu_frame_upload_texture (self, FALSE, texture, &color_state);
   if (image == NULL)
     {
       g_critical ("Could not upload texture");

gsk/gpu/gskgpuframeprivate.h

@@ -58,7 +58,8 @@ gpointer                gsk_gpu_frame_alloc_op                          (GskGpuF
                                                                          gsize                   size);
 GskGpuImage *           gsk_gpu_frame_upload_texture                    (GskGpuFrame            *self,
                                                                          gboolean                with_mipmap,
-                                                                         GdkTexture             *texture);
+                                                                         GdkTexture             *texture,
+                                                                         GdkColorState         **out_color_state);
 GskGpuDescriptors *     gsk_gpu_frame_create_descriptors                (GskGpuFrame            *self);
 gsize                   gsk_gpu_frame_reserve_vertex_data               (GskGpuFrame            *self,
                                                                          gsize                   size);
@@ -75,6 +76,7 @@ void                    gsk_gpu_frame_wait                              (GskGpuF
 void                    gsk_gpu_frame_render                            (GskGpuFrame            *self,
                                                                          gint64                  timestamp,
                                                                          GskGpuImage            *target,
+                                                                         GdkColorState          *target_color_state,
                                                                          const cairo_region_t   *region,
                                                                          GskRenderNode          *node,
                                                                          const graphene_rect_t  *viewport,

gsk/gpu/gskgpuimage.c

@@ -114,7 +114,7 @@ gsk_gpu_image_toggle_ref_texture (GskGpuImage *self,
   g_object_add_toggle_ref (G_OBJECT (self), gsk_gpu_image_texture_toggle_ref_cb, texture);
   g_object_unref (self);
 }
-                     
+
 GdkMemoryFormat
 gsk_gpu_image_get_format (GskGpuImage *self)
 {

gsk/gpu/gskgpunodeprocessor.c

@@ -10,6 +10,7 @@
 #include "gskgpubluropprivate.h"
 #include "gskgpuclearopprivate.h"
 #include "gskgpuclipprivate.h"
+#include "gskgpucolorconvertopprivate.h"
 #include "gskgpucolorizeopprivate.h"
 #include "gskgpucolormatrixopprivate.h"
 #include "gskgpucoloropprivate.h"
@@ -44,6 +45,7 @@
 
 #include "gdk/gdkrgbaprivate.h"
 #include "gdk/gdksubsurfaceprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 /* the epsilon we allow pixels to be off due to rounding errors.
  * Chosen rather randomly.
@@ -120,6 +122,7 @@ struct _GskGpuNodeProcessor
   float                          opacity;
 
   GskGpuGlobals                  pending_globals;
+  GdkColorState                 *color_state;
 };
 
 #define GDK_ARRAY_NAME pattern_buffer
@@ -141,6 +144,7 @@ struct _GskGpuPatternWriter
   guint                          stack;
 
   PatternBuffer                  buffer;
+  GdkColorState                 *color_state;
 };
 
 static void             gsk_gpu_node_processor_add_node                 (GskGpuNodeProcessor            *self,
@@ -153,6 +157,7 @@ gsk_gpu_node_processor_finish (GskGpuNodeProcessor *self)
 {
   g_clear_pointer (&self->modelview, gsk_transform_unref);
   g_clear_object (&self->desc);
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
 }
 
 static void
@@ -160,6 +165,7 @@ gsk_gpu_node_processor_init (GskGpuNodeProcessor         *self,
                              GskGpuFrame                 *frame,
                              GskGpuDescriptors           *desc,
                              GskGpuImage                 *target,
+                             GdkColorState               *color_state,
                              const cairo_rectangle_int_t *clip,
                              const graphene_rect_t       *viewport)
 {
@@ -202,6 +208,8 @@ gsk_gpu_node_processor_init (GskGpuNodeProcessor         *self,
                                       -viewport->origin.y);
   self->opacity = 1.0;
   self->pending_globals = GSK_GPU_GLOBAL_MATRIX | GSK_GPU_GLOBAL_SCALE | GSK_GPU_GLOBAL_CLIP | GSK_GPU_GLOBAL_SCISSOR | GSK_GPU_GLOBAL_BLEND;
+
+  self->color_state = gdk_color_state_ref (color_state);
 }
 
 static void
@@ -338,6 +346,7 @@ gsk_gpu_node_processor_init_draw (GskGpuNodeProcessor   *self,
                                   GskGpuFrame           *frame,
                                   GdkMemoryDepth         depth,
                                   const graphene_vec2_t *scale,
+                                  GdkColorState         *color_state,
                                   const graphene_rect_t *viewport)
 {
   GskGpuImage *image;
@@ -359,6 +368,7 @@ gsk_gpu_node_processor_init_draw (GskGpuNodeProcessor   *self,
                                frame,
                                NULL,
                                image,
+                               color_state,
                                &area,
                                viewport);
 
@@ -381,9 +391,97 @@ gsk_gpu_node_processor_finish_draw (GskGpuNodeProcessor *self,
   gsk_gpu_node_processor_finish (self);
 }
 
+static GskGpuImage *
+gsk_gpu_color_convert (GskGpuFrame   *frame,
+                       GskGpuImage   *image,
+                       GdkColorState *from,
+                       GdkColorState *to)
+{
+  GskGpuNodeProcessor other;
+  int width, height;
+  GdkMemoryDepth depth;
+  GskGpuImage *copy;
+  guint32 descriptor;
+  graphene_rect_t rect;
+
+  if (gdk_color_state_equal (from, to))
+    return image;
+
+  width = gsk_gpu_image_get_width (image);
+  height = gsk_gpu_image_get_height (image);
+  depth = gdk_memory_format_get_depth (gsk_gpu_image_get_format (image));
+  depth = gdk_memory_depth_merge (depth, gdk_color_state_get_min_depth (from));
+  depth = gdk_memory_depth_merge (depth, gdk_color_state_get_min_depth (to));
+  rect = GRAPHENE_RECT_INIT (0, 0, width, height);
+
+  copy = gsk_gpu_device_create_offscreen_image (gsk_gpu_frame_get_device (frame),
+                                                FALSE,
+                                                depth,
+                                                width, height);
+
+  gsk_gpu_node_processor_init (&other,
+                               frame,
+                               NULL,
+                               copy,
+                               to,
+                               &(cairo_rectangle_int_t) { 0, 0, width, height },
+                               &rect);
+
+  gsk_gpu_render_pass_begin_op (other.frame,
+                                copy,
+                                &(cairo_rectangle_int_t) { 0, 0, width, height },
+                                GSK_RENDER_PASS_OFFSCREEN);
+
+  descriptor = gsk_gpu_node_processor_add_image (&other, image, GSK_GPU_SAMPLER_DEFAULT);
+
+  gsk_gpu_node_processor_sync_globals (&other, 0);
+
+  gsk_gpu_color_convert_op (frame,
+                            GSK_GPU_SHADER_CLIP_NONE,
+                            from,
+                            to,
+                            other.desc,
+                            descriptor,
+                            &rect,
+                            &other.offset,
+                            &rect);
+
+  gsk_gpu_render_pass_end_op (other.frame,
+                              copy,
+                              GSK_RENDER_PASS_OFFSCREEN);
+
+  gsk_gpu_node_processor_finish (&other);
+
+  g_object_unref (image);
+
+  return copy;
+}
+
+static void
+gsk_gpu_node_processor_get_clip_bounds (GskGpuNodeProcessor *self,
+                                        graphene_rect_t     *out_bounds)
+{
+  graphene_rect_offset_r (&self->clip.rect.bounds,
+                          - self->offset.x,
+                          - self->offset.y,
+                          out_bounds);
+
+  /* FIXME: We could try the scissor rect here.
+   * But how often is that smaller than the clip bounds?
+   */
+}
+
+static GskGpuImage * gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
+                                                const graphene_rect_t  *clip_bounds,
+                                                const graphene_vec2_t  *scale,
+                                                GdkColorState          *color_state,
+                                                GskRenderNode          *node,
+                                                graphene_rect_t        *out_bounds);
+
 void
 gsk_gpu_node_processor_process (GskGpuFrame                 *frame,
                                 GskGpuImage                 *target,
+                                GdkColorState               *target_color_state,
                                 const cairo_rectangle_int_t *clip,
                                 GskRenderNode               *node,
                                 const graphene_rect_t       *viewport)
@@ -394,10 +492,46 @@ gsk_gpu_node_processor_process (GskGpuFrame                 *frame,
                                frame,
                                NULL,
                                target,
+                               GDK_COLOR_STATE_SRGB_LINEAR,
                                clip,
                                viewport);
 
-  gsk_gpu_node_processor_add_node (&self, node);
+  if (gdk_color_state_equal (target_color_state, GDK_COLOR_STATE_SRGB_LINEAR))
+    {
+      gsk_gpu_node_processor_add_node (&self, node);
+    }
+  else
+    {
+      GskGpuImage *image;
+      graphene_rect_t clip_bounds;
+      graphene_rect_t bounds;
+      guint32 descriptor;
+
+      gsk_gpu_node_processor_sync_globals (&self, 0);
+
+      gsk_gpu_node_processor_get_clip_bounds (&self, &clip_bounds);
+
+      image = gsk_gpu_get_node_as_image (frame,
+                                         &clip_bounds,
+                                         &self.scale,
+                                         GDK_COLOR_STATE_SRGB_LINEAR,
+                                         node,
+                                         &bounds);
+
+      descriptor = gsk_gpu_node_processor_add_image (&self, image, GSK_GPU_SAMPLER_DEFAULT);
+
+      gsk_gpu_color_convert_op (frame,
+                                GSK_GPU_SHADER_CLIP_NONE,
+                                GDK_COLOR_STATE_SRGB_LINEAR,
+                                target_color_state,
+                                self.desc,
+                                descriptor,
+                                &bounds,
+                                &self.offset,
+                                &bounds);
+
+      g_object_unref (image);
+    }
 
   gsk_gpu_node_processor_finish (&self);
 }
@@ -406,6 +540,7 @@ static void
 gsk_gpu_pattern_writer_init (GskGpuPatternWriter    *self,
                              GskGpuFrame            *frame,
                              const graphene_vec2_t  *scale,
+                             GdkColorState          *color_state,
                              const graphene_point_t *offset,
                              const graphene_rect_t  *bounds)
 {
@@ -419,6 +554,8 @@ gsk_gpu_pattern_writer_init (GskGpuPatternWriter    *self,
   self->scale = *scale;
   self->stack = 0;
 
+  self->color_state = gdk_color_state_ref (color_state);
+
   pattern_buffer_init (&self->buffer);
 }
 
@@ -546,6 +683,7 @@ gsk_gpu_pattern_writer_finish (GskGpuPatternWriter *self)
   pattern_buffer_clear (&self->buffer);
   g_assert (self->stack == 0);
   g_clear_object (&self->desc);
+  g_clear_pointer (&self->color_state, gdk_color_state_unref);
 }
 
 static gboolean
@@ -664,20 +802,6 @@ gsk_gpu_node_processor_rect_is_integer (GskGpuNodeProcessor   *self,
       && int_rect->height == rect->size.height * scale_y;
 }
 
-static void
-gsk_gpu_node_processor_get_clip_bounds (GskGpuNodeProcessor *self,
-                                        graphene_rect_t     *out_bounds)
-{
-  graphene_rect_offset_r (&self->clip.rect.bounds,
-                          - self->offset.x,
-                          - self->offset.y,
-                          out_bounds);
- 
-  /* FIXME: We could try the scissor rect here.
-   * But how often is that smaller than the clip bounds?
-   */
-}
- 
 static gboolean G_GNUC_WARN_UNUSED_RESULT
 gsk_gpu_node_processor_clip_node_bounds (GskGpuNodeProcessor *self,
                                          GskRenderNode       *node,
@@ -742,6 +866,7 @@ gsk_gpu_node_processor_image_op (GskGpuNodeProcessor   *self,
 static GskGpuImage *
 gsk_gpu_node_processor_create_offscreen (GskGpuFrame           *frame,
                                          const graphene_vec2_t *scale,
+                                         GdkColorState         *color_state,
                                          const graphene_rect_t *viewport,
                                          GskRenderNode         *node)
 {
@@ -752,6 +877,7 @@ gsk_gpu_node_processor_create_offscreen (GskGpuFrame           *frame,
                                             frame,
                                             gsk_render_node_get_preferred_depth (node),
                                             scale,
+                                            color_state,
                                             viewport);
   if (image == NULL)
     return NULL;
@@ -768,6 +894,7 @@ gsk_gpu_node_processor_create_offscreen (GskGpuFrame           *frame,
  * @frame: frame to render in
  * @clip_bounds: region of node that must be included in image
  * @scale: scale factor to use for the image
+ * @color_state: the color state to composite in
  * @node: the node to render
  * @out_bounds: the actual bounds of the result
  *
@@ -789,10 +916,12 @@ static GskGpuImage *
 gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
                            const graphene_rect_t  *clip_bounds,
                            const graphene_vec2_t  *scale,
+                           GdkColorState          *color_state,
                            GskRenderNode          *node,
                            graphene_rect_t        *out_bounds)
 {
   GskGpuImage *result;
+  GdkColorState *image_color_state;
 
   switch ((guint) gsk_render_node_get_node_type (node))
     {
@@ -801,9 +930,19 @@ gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
         GdkTexture *texture = gsk_texture_node_get_texture (node);
         GskGpuDevice *device = gsk_gpu_frame_get_device (frame);
         gint64 timestamp = gsk_gpu_frame_get_timestamp (frame);
-        result = gsk_gpu_device_lookup_texture_image (device, texture, timestamp);
+
+        result = gsk_gpu_device_lookup_texture_image (device, texture, color_state, timestamp);
         if (result == NULL)
-          result = gsk_gpu_frame_upload_texture (frame, FALSE, texture);
+          {
+            result = gsk_gpu_frame_upload_texture (frame, FALSE, texture, &image_color_state);
+
+            if (result &&
+                !gdk_color_state_equal (image_color_state, color_state))
+              {
+                result = gsk_gpu_color_convert (frame, result, image_color_state, color_state);
+                gsk_gpu_device_cache_texture_image (device, texture, timestamp, result, color_state);
+              }
+          }
 
         if (result)
           {
@@ -821,6 +960,8 @@ gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
                                         gsk_render_node_ref (node),
                                         (GDestroyNotify) gsk_render_node_unref);
 
+      result = gsk_gpu_color_convert (frame, result, GDK_COLOR_STATE_SRGB, color_state);
+
       g_object_ref (result);
 
       *out_bounds = *clip_bounds;
@@ -833,6 +974,7 @@ gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
   GSK_DEBUG (FALLBACK, "Offscreening node '%s'", g_type_name_from_instance ((GTypeInstance *) node));
   result = gsk_gpu_node_processor_create_offscreen (frame,
                                                     scale,
+                                                    color_state,
                                                     clip_bounds,
                                                     node);
 
@@ -843,6 +985,7 @@ gsk_gpu_get_node_as_image (GskGpuFrame            *frame,
 static GskGpuImage *
 gsk_gpu_node_processor_ensure_image (GskGpuFrame      *frame,
                                      GskGpuImage      *image,
+                                     GdkColorState    *color_state,
                                      GskGpuImageFlags  required_flags,
                                      GskGpuImageFlags  disallowed_flags)
 {
@@ -895,6 +1038,7 @@ gsk_gpu_node_processor_ensure_image (GskGpuFrame      *frame,
                                    frame,
                                    NULL,
                                    copy,
+                                   color_state,
                                    &(cairo_rectangle_int_t) { 0, 0, width, height },
                                    &rect);
 
@@ -968,6 +1112,7 @@ gsk_gpu_node_processor_get_node_as_image (GskGpuNodeProcessor   *self,
   image = gsk_gpu_get_node_as_image (self->frame,
                                      &clip,
                                      &self->scale,
+                                     self->color_state,
                                      node,
                                      out_bounds);
   if (image == NULL)
@@ -975,6 +1120,7 @@ gsk_gpu_node_processor_get_node_as_image (GskGpuNodeProcessor   *self,
 
   ensure = gsk_gpu_node_processor_ensure_image (self->frame,
                                                 image,
+                                                self->color_state,
                                                 required_flags,
                                                 disallowed_flags);
 
@@ -985,7 +1131,8 @@ gsk_gpu_node_processor_get_node_as_image (GskGpuNodeProcessor   *self,
       gsk_gpu_device_cache_texture_image (gsk_gpu_frame_get_device (self->frame),
                                           gsk_texture_node_get_texture (node),
                                           gsk_gpu_frame_get_timestamp (self->frame),
-                                          ensure);
+                                          ensure,
+                                          self->color_state);
     }
 
   return ensure;
@@ -1026,6 +1173,7 @@ gsk_gpu_node_processor_blur_op (GskGpuNodeProcessor       *self,
                                                    self->frame,
                                                    source_depth,
                                                    &self->scale,
+                                                   self->color_state,
                                                    &intermediate_rect);
 
   gsk_gpu_node_processor_sync_globals (&other, 0);
@@ -1205,6 +1353,7 @@ gsk_gpu_node_processor_try_node_as_pattern (GskGpuNodeProcessor *self,
   gsk_gpu_pattern_writer_init (&writer,
                                self->frame,
                                &self->scale,
+                               self->color_state,
                                &self->offset,
                                &clipped);
  
@@ -1454,6 +1603,7 @@ gsk_gpu_node_processor_add_rounded_clip_node_with_mask (GskGpuNodeProcessor *sel
                                                  self->frame,
                                                  gsk_render_node_get_preferred_depth (node),
                                                  &self->scale,
+                                                 self->color_state,
                                                  &clip_bounds);
   gsk_gpu_node_processor_sync_globals (&other, 0);
   gsk_gpu_rounded_color_op (other.frame,
@@ -1927,15 +2077,16 @@ gsk_gpu_node_processor_add_texture_node (GskGpuNodeProcessor *self,
   GskGpuImage *image;
   GdkTexture *texture;
   gint64 timestamp;
+  GdkColorState *image_color_state;
 
   device = gsk_gpu_frame_get_device (self->frame);
   texture = gsk_texture_node_get_texture (node);
   timestamp = gsk_gpu_frame_get_timestamp (self->frame);
 
-  image = gsk_gpu_device_lookup_texture_image (device, texture, timestamp);
+  image = gsk_gpu_device_lookup_texture_image (device, texture, self->color_state, timestamp);
   if (image == NULL)
     {
-      image = gsk_gpu_frame_upload_texture (self->frame, FALSE, texture);
+      image = gsk_gpu_frame_upload_texture (self->frame, FALSE, texture, &image_color_state);
       if (image == NULL)
         {
           GSK_DEBUG (FALLBACK, "Unsupported texture format %u for size %dx%d",
@@ -1945,6 +2096,12 @@ gsk_gpu_node_processor_add_texture_node (GskGpuNodeProcessor *self,
           gsk_gpu_node_processor_add_fallback_node (self, node);
           return;
         }
+
+      if (!gdk_color_state_equal (image_color_state, self->color_state))
+        {
+          image = gsk_gpu_color_convert (self->frame, image, image_color_state, self->color_state);
+          gsk_gpu_device_cache_texture_image (device, texture, timestamp, image, self->color_state);
+        }
     }
 
   if (gsk_gpu_frame_should_optimize (self->frame, GSK_GPU_OPTIMIZE_MIPMAP) &&
@@ -1955,6 +2112,7 @@ gsk_gpu_node_processor_add_texture_node (GskGpuNodeProcessor *self,
 
       image = gsk_gpu_node_processor_ensure_image (self->frame,
                                                    image,
+                                                   self->color_state,
                                                    GSK_GPU_IMAGE_MIPMAP,
                                                    GSK_GPU_IMAGE_STRAIGHT_ALPHA);
       descriptor = gsk_gpu_node_processor_add_image (self, image, GSK_GPU_SAMPLER_MIPMAP_DEFAULT);
@@ -2001,17 +2159,24 @@ gsk_gpu_node_processor_create_texture_pattern (GskGpuPatternWriter *self,
   guint32 descriptor;
   GskGpuImage *image;
   GskGpuSampler sampler;
+  GdkColorState *image_color_state;
 
   device = gsk_gpu_frame_get_device (self->frame);
   texture = gsk_texture_node_get_texture (node);
   timestamp = gsk_gpu_frame_get_timestamp (self->frame);
 
-  image = gsk_gpu_device_lookup_texture_image (device, texture, timestamp);
+  image = gsk_gpu_device_lookup_texture_image (device, texture, self->color_state, timestamp);
   if (image == NULL)
     {
-      image = gsk_gpu_frame_upload_texture (self->frame, FALSE, texture);
+      image = gsk_gpu_frame_upload_texture (self->frame, FALSE, texture, &image_color_state);
       if (image == NULL)
         return FALSE;
+
+      if (!gdk_color_state_equal (image_color_state, self->color_state))
+        {
+          image = gsk_gpu_color_convert (self->frame, image, image_color_state, self->color_state);
+          gsk_gpu_device_cache_texture_image (device, texture, timestamp, image, self->color_state);
+        }
     }
 
   if (gsk_gpu_frame_should_optimize (self->frame, GSK_GPU_OPTIMIZE_MIPMAP) &&
@@ -2020,6 +2185,7 @@ gsk_gpu_node_processor_create_texture_pattern (GskGpuPatternWriter *self,
     {
       image = gsk_gpu_node_processor_ensure_image (self->frame,
                                                    image,
+                                                   self->color_state,
                                                    GSK_GPU_IMAGE_MIPMAP,
                                                    GSK_GPU_IMAGE_STRAIGHT_ALPHA);
       sampler = GSK_GPU_SAMPLER_MIPMAP_DEFAULT;
@@ -2058,6 +2224,7 @@ gsk_gpu_node_processor_add_texture_scale_node (GskGpuNodeProcessor *self,
   gint64 timestamp;
   guint32 descriptor;
   gboolean need_mipmap, need_offscreen;
+  GdkColorState *image_color_state;
 
   need_offscreen = self->modelview != NULL ||
             !graphene_vec2_equal (&self->scale, graphene_vec2_one ());
@@ -2081,6 +2248,7 @@ gsk_gpu_node_processor_add_texture_scale_node (GskGpuNodeProcessor *self,
       clip_bounds.size.height = ceilf (clip_bounds.size.height);
       offscreen = gsk_gpu_node_processor_create_offscreen (self->frame,
                                                            graphene_vec2_one (),
+                                                           self->color_state,
                                                            &clip_bounds,
                                                            node);
       descriptor = gsk_gpu_node_processor_add_image (self, offscreen, GSK_GPU_SAMPLER_DEFAULT);
@@ -2101,10 +2269,10 @@ gsk_gpu_node_processor_add_texture_scale_node (GskGpuNodeProcessor *self,
   timestamp = gsk_gpu_frame_get_timestamp (self->frame);
   need_mipmap = scaling_filter == GSK_SCALING_FILTER_TRILINEAR;
 
-  image = gsk_gpu_device_lookup_texture_image (device, texture, timestamp);
+  image = gsk_gpu_device_lookup_texture_image (device, texture, self->color_state, timestamp);
   if (image == NULL)
     {
-      image = gsk_gpu_frame_upload_texture (self->frame, need_mipmap, texture);
+      image = gsk_gpu_frame_upload_texture (self->frame, need_mipmap, texture, &image_color_state);
       if (image == NULL)
         {
           GSK_DEBUG (FALLBACK, "Unsupported texture format %u for size %dx%d",
@@ -2114,10 +2282,16 @@ gsk_gpu_node_processor_add_texture_scale_node (GskGpuNodeProcessor *self,
           gsk_gpu_node_processor_add_fallback_node (self, node);
           return;
         }
+      if (!gdk_color_state_equal (image_color_state, self->color_state))
+        {
+          image = gsk_gpu_color_convert (self->frame, image, image_color_state, self->color_state);
+          gsk_gpu_device_cache_texture_image (device, texture, timestamp, image, self->color_state);
+        }
     }
 
   image = gsk_gpu_node_processor_ensure_image (self->frame,
                                                image,
+                                               self->color_state,
                                                need_mipmap ? (GSK_GPU_IMAGE_CAN_MIPMAP | GSK_GPU_IMAGE_MIPMAP) : 0,
                                                GSK_GPU_IMAGE_STRAIGHT_ALPHA);
 
@@ -2282,6 +2456,7 @@ gsk_gpu_node_processor_add_gradient_node (GskGpuNodeProcessor *self,
                                             self->frame,
                                             gsk_render_node_get_preferred_depth (node),
                                             &self->scale,
+                                            self->color_state,
                                             &bounds);
 
   other.blend = GSK_GPU_BLEND_ADD;
@@ -3331,6 +3506,7 @@ gsk_gpu_node_processor_repeat_tile (GskGpuNodeProcessor    *self,
   GSK_DEBUG (FALLBACK, "Offscreening node '%s' for tiling", g_type_name_from_instance ((GTypeInstance *) child));
   image = gsk_gpu_node_processor_create_offscreen (self->frame,
                                                    &self->scale,
+                                                   self->color_state,
                                                    &clipped_child_bounds,
                                                    child);
 
@@ -4123,6 +4299,7 @@ gsk_gpu_node_processor_create_node_pattern (GskGpuPatternWriter *self,
   image = gsk_gpu_get_node_as_image (self->frame,
                                      &bounds,
                                      &self->scale,
+                                     self->color_state,
                                      node,
                                      &bounds);
   if (image == NULL)

gsk/gpu/gskgpunodeprocessorprivate.h

@@ -7,6 +7,7 @@ G_BEGIN_DECLS
 
 void                    gsk_gpu_node_processor_process                  (GskGpuFrame                    *frame,
                                                                          GskGpuImage                    *target,
+                                                                         GdkColorState                  *target_color_state,
                                                                          const cairo_rectangle_int_t    *clip,
                                                                          GskRenderNode                  *node,
                                                                          const graphene_rect_t          *viewport);

gsk/gpu/gskgpuprint.c

@@ -2,6 +2,8 @@
 
 #include "gskgpuprintprivate.h"
 
+#include "gdk/gdkrgbaprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 #include "gskgpudescriptorsprivate.h"
 #include "gskgpuimageprivate.h"
 
@@ -155,3 +157,11 @@ gsk_gpu_print_image_descriptor (GString           *string,
   gsk_gpu_print_image (string, gsk_gpu_descriptors_get_image (desc, id));
 }
 
+void
+gsk_gpu_print_color_conversion (GString *string,
+                                guint    conversion)
+{
+  g_string_append_printf (string, "%s->%s ",
+                          gdk_color_state_get_name_from_id (conversion & 0xffff),
+                          gdk_color_state_get_name_from_id (conversion >> 16));
+}

gsk/gpu/gskgpuprintprivate.h

@@ -35,3 +35,5 @@ void                    gsk_gpu_print_image                             (GString
 void                    gsk_gpu_print_image_descriptor                  (GString                        *string,
                                                                          GskGpuDescriptors              *desc,
                                                                          guint32                         descriptor);
+void                    gsk_gpu_print_color_conversion                  (GString                        *string,
+                                                                         guint                           conversion);

gsk/gpu/gskgpurenderer.c

@@ -18,6 +18,7 @@
 #include "gdk/gdktextureprivate.h"
 #include "gdk/gdktexturedownloaderprivate.h"
 #include "gdk/gdkdrawcontextprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #include <graphene.h>
 
@@ -298,6 +299,7 @@ gsk_gpu_renderer_fallback_render_texture (GskGpuRenderer        *self,
           gsk_gpu_frame_render (frame,
                                 g_get_monotonic_time (),
                                 image,
+                                GDK_COLOR_STATE_SRGB,
                                 NULL,
                                 root,
                                 &GRAPHENE_RECT_INIT (rounded_viewport->origin.x + x,
@@ -360,6 +362,7 @@ gsk_gpu_renderer_render_texture (GskRenderer           *renderer,
   gsk_gpu_frame_render (frame,
                         g_get_monotonic_time (),
                         image,
+                        GDK_COLOR_STATE_SRGB,
                         NULL,
                         root,
                         &rounded_viewport,
@@ -387,6 +390,8 @@ gsk_gpu_renderer_render (GskRenderer          *renderer,
   GskGpuImage *backbuffer;
   cairo_region_t *render_region;
   double scale;
+  GdkMemoryDepth depth;
+  GdkColorState *target_color_state;
 
   if (cairo_region_is_empty (region))
     {
@@ -394,9 +399,9 @@ gsk_gpu_renderer_render (GskRenderer          *renderer,
       return;
     }
 
-  gdk_draw_context_begin_frame_full (priv->context,
-                                     gsk_render_node_get_preferred_depth (root),
-                                     region);
+  depth = gsk_render_node_get_preferred_depth (root);
+
+  gdk_draw_context_begin_frame_full (priv->context, depth, region);
 
   gsk_gpu_device_maybe_gc (priv->device);
 
@@ -408,9 +413,21 @@ gsk_gpu_renderer_render (GskRenderer          *renderer,
   render_region = get_render_region (self);
   scale = gsk_gpu_renderer_get_scale (self);
 
+  if (gsk_gpu_image_get_flags (backbuffer) & GSK_GPU_IMAGE_SRGB)
+    {
+      g_debug ("Relying on GL/Vulkan to do srgb-linear->srgb conversion");
+      target_color_state = GDK_COLOR_STATE_SRGB_LINEAR;
+    }
+  else
+    {
+      g_debug ("Using an offscreen for srgb-linear->srgb conversion");
+      target_color_state = GDK_COLOR_STATE_SRGB;
+    }
+
   gsk_gpu_frame_render (frame,
                         g_get_monotonic_time (),
                         backbuffer,
+                        target_color_state,
                         render_region,
                         root,
                         &GRAPHENE_RECT_INIT (

gsk/gpu/gskgpushaderopprivate.h

@@ -4,6 +4,8 @@
 
 #include "gskgputypesprivate.h"
 
+#include <math.h>
+
 G_BEGIN_DECLS
 
 struct _GskGpuShaderOp
@@ -63,13 +65,23 @@ GskGpuOp *              gsk_gpu_shader_op_gl_command                    (GskGpuO
                                                                          GskGpuFrame            *frame,
                                                                          GskGLCommandState      *state);
 
+
+static inline float
+srgb_inverse_transfer_function (float v)
+{
+  if (v >= 0.04045)
+    return powf (((v + 0.055)/(1 + 0.055)), 2.4);
+  else
+    return v / 12.92;
+}
+
 static inline void
 gsk_gpu_rgba_to_float (const GdkRGBA *rgba,
                        float          values[4])
 {
-  values[0] = rgba->red;
-  values[1] = rgba->green;
-  values[2] = rgba->blue;
+  values[0] = srgb_inverse_transfer_function (rgba->red);
+  values[1] = srgb_inverse_transfer_function (rgba->green);
+  values[2] = srgb_inverse_transfer_function (rgba->blue);
   values[3] = rgba->alpha;
 }
 

gsk/gpu/gskgputypesprivate.h

@@ -29,6 +29,7 @@ typedef enum {
   GSK_GPU_IMAGE_MIPMAP         = (1 << 5),
   GSK_GPU_IMAGE_FILTERABLE     = (1 << 6),
   GSK_GPU_IMAGE_RENDERABLE     = (1 << 7),
+  GSK_GPU_IMAGE_SRGB           = (1 << 8),
 } GskGpuImageFlags;
 
 typedef enum {

gsk/gpu/gskgpuuploadop.c

@@ -14,6 +14,15 @@
 
 #include "gdk/gdkglcontextprivate.h"
 #include "gsk/gskdebugprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
+
+
+#ifdef HAVE_PANGOFT
+#include <pango/pangofc-font.h>
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_PARAMETER_TAGS_H
+#endif
 
 static GskGpuOp *
 gsk_gpu_upload_op_gl_command_with_area (GskGpuOp                    *op,
@@ -304,6 +313,7 @@ gsk_gpu_upload_texture_op_try (GskGpuFrame *frame,
   image = gsk_gpu_device_create_upload_image (gsk_gpu_frame_get_device (frame),
                                               with_mipmap,
                                               gdk_texture_get_format (texture),
+                                              gdk_texture_get_color_state (texture),
                                               gdk_texture_get_width (texture),
                                               gdk_texture_get_height (texture));
   if (image == NULL)
@@ -470,6 +480,7 @@ gsk_gpu_upload_cairo_op (GskGpuFrame           *frame,
   self->image = gsk_gpu_device_create_upload_image (gsk_gpu_frame_get_device (frame),
                                                     FALSE,
                                                     GDK_MEMORY_DEFAULT,
+                                                    GDK_COLOR_STATE_SRGB,
                                                     ceil (graphene_vec2_get_x (scale) * viewport->size.width),
                                                     ceil (graphene_vec2_get_y (scale) * viewport->size.height));
   self->viewport = *viewport;
@@ -537,6 +548,16 @@ gsk_gpu_upload_glyph_op_draw (GskGpuOp *op,
   cairo_surface_t *surface;
   cairo_t *cr;
   PangoRectangle ink_rect = { 0, };
+#ifdef HAVE_PANGOFT
+  FT_Face face;
+  FT_Bool darken = 1;
+  FT_Parameter property = { FT_PARAM_TAG_STEM_DARKENING, &darken };
+
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  face = pango_fc_font_lock_face (PANGO_FC_FONT (self->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+  FT_Face_Properties (face, 1, &property);
+#endif
 
   surface = cairo_image_surface_create_for_data (data,
                                                  CAIRO_FORMAT_ARGB32,
@@ -578,6 +599,12 @@ gsk_gpu_upload_glyph_op_draw (GskGpuOp *op,
 
   cairo_surface_finish (surface);
   cairo_surface_destroy (surface);
+
+#ifdef HAVE_PANGOFT
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  pango_fc_font_unlock_face (PANGO_FC_FONT (self->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+#endif
 }
 
 #ifdef GDK_RENDERING_VULKAN

gsk/gpu/gsknglrenderer.c

@@ -117,7 +117,8 @@ gsk_ngl_renderer_get_backbuffer (GskGpuRenderer *renderer)
                                                       GDK_GL_CONTEXT (context),
                                                       GDK_MEMORY_DEFAULT /* FIXME */,
                                                       ceil (gdk_surface_get_width (surface) * scale),
-                                                      ceil (gdk_surface_get_height (surface) * scale));
+                                                      ceil (gdk_surface_get_height (surface) * scale),
+                                                      gdk_surface_get_gl_is_srgb (surface));
     }
 
   return self->backbuffer;

gsk/gpu/gskvulkandevice.c

@@ -391,6 +391,7 @@ static GskGpuImage *
 gsk_vulkan_device_create_upload_image (GskGpuDevice    *device,
                                        gboolean         with_mipmap,
                                        GdkMemoryFormat  format,
+                                       GdkColorState   *color_state,
                                        gsize            width,
                                        gsize            height)
 {
@@ -399,6 +400,7 @@ gsk_vulkan_device_create_upload_image (GskGpuDevice    *device,
   return gsk_vulkan_image_new_for_upload (self,
                                           with_mipmap,
                                           format,
+                                          color_state,
                                           width,
                                           height);
 }

gsk/gpu/gskvulkanimage.c

@@ -11,6 +11,7 @@
 #include "gdk/gdkvulkancontextprivate.h"
 #include "gdk/gdkmemoryformatprivate.h"
 #include "gdk/gdkvulkancontextprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #include <fcntl.h>
 #include <string.h>
@@ -243,6 +244,7 @@ gsk_vulkan_device_check_format (GskVulkanDevice          *device,
 static GskVulkanImage *
 gsk_vulkan_image_new (GskVulkanDevice           *device,
                       GdkMemoryFormat            format,
+                      GdkColorState             *color_state,
                       GskGpuImageFlags           required_flags,
                       gsize                      width,
                       gsize                      height,
@@ -305,6 +307,13 @@ gsk_vulkan_image_new (GskVulkanDevice           *device,
       (required_flags & GSK_GPU_IMAGE_CAN_MIPMAP))
     flags |= GSK_GPU_IMAGE_CAN_MIPMAP;
 
+  if (gdk_memory_format_vk_srgb_format (format) != VK_FORMAT_UNDEFINED &&
+      gdk_color_state_equal (color_state, GDK_COLOR_STATE_SRGB))
+    {
+      vk_format = gdk_memory_format_vk_srgb_format (format);
+      flags |= GSK_GPU_IMAGE_SRGB;
+    }
+
   vk_device = gsk_vulkan_device_get_vk_device (device);
 
   self = g_object_new (GSK_TYPE_VULKAN_IMAGE, NULL);
@@ -366,6 +375,7 @@ GskGpuImage *
 gsk_vulkan_image_new_for_upload (GskVulkanDevice *device,
                                  gboolean         with_mipmap,
                                  GdkMemoryFormat  format,
+                                 GdkColorState   *color_state,
                                  gsize            width,
                                  gsize            height)
 {
@@ -373,6 +383,7 @@ gsk_vulkan_image_new_for_upload (GskVulkanDevice *device,
 
   self = gsk_vulkan_image_new (device,
                                format,
+                               color_state,
                                with_mipmap ? (GSK_GPU_IMAGE_CAN_MIPMAP | GSK_GPU_IMAGE_RENDERABLE | GSK_GPU_IMAGE_FILTERABLE) : 0,
                                width,
                                height,
@@ -438,6 +449,7 @@ gsk_vulkan_image_new_for_swapchain (GskVulkanDevice  *device,
                                     gsize             height)
 {
   GskVulkanImage *self;
+  GskGpuImageFlags flags = 0;
 
   self = g_object_new (GSK_TYPE_VULKAN_IMAGE, NULL);
 
@@ -450,9 +462,11 @@ gsk_vulkan_image_new_for_swapchain (GskVulkanDevice  *device,
   self->vk_image_layout = VK_IMAGE_LAYOUT_UNDEFINED;
   self->vk_access = 0;
 
-  /* FIXME: The flags here are very suboptimal */
-  gsk_gpu_image_setup (GSK_GPU_IMAGE (self), 0, memory_format, width, height);
+  if (format == gdk_memory_format_vk_srgb_format (memory_format))
+    flags |= GSK_GPU_IMAGE_SRGB;
 
+  /* FIXME: The flags here are very suboptimal */
+  gsk_gpu_image_setup (GSK_GPU_IMAGE (self), flags, memory_format, width, height);
   gsk_vulkan_image_create_view (self,
                                 format,
                                 &(VkComponentMapping) {
@@ -475,6 +489,7 @@ gsk_vulkan_image_new_for_atlas (GskVulkanDevice *device,
 
   self = gsk_vulkan_image_new (device,
                                GDK_MEMORY_DEFAULT,
+                               GDK_COLOR_STATE_SRGB_LINEAR,
                                GSK_GPU_IMAGE_FILTERABLE | GSK_GPU_IMAGE_RENDERABLE,
                                width,
                                height,
@@ -499,6 +514,7 @@ gsk_vulkan_image_new_for_offscreen (GskVulkanDevice *device,
 
   self = gsk_vulkan_image_new (device,
                                preferred_format,
+                               GDK_COLOR_STATE_SRGB_LINEAR,
                                GSK_GPU_IMAGE_RENDERABLE |
                                (with_mipmap ? GSK_GPU_IMAGE_CAN_MIPMAP | GSK_GPU_IMAGE_FILTERABLE : 0),
                                width,

gsk/gpu/gskvulkanimageprivate.h

@@ -29,6 +29,7 @@ GskGpuImage *           gsk_vulkan_image_new_for_offscreen              (GskVulk
 GskGpuImage *           gsk_vulkan_image_new_for_upload                 (GskVulkanDevice        *device,
                                                                          gboolean                with_mipmap,
                                                                          GdkMemoryFormat         format,
+                                                                         GdkColorState          *color_state,
                                                                          gsize                   width,
                                                                          gsize                   height);
 #ifdef HAVE_DMABUF

gsk/gpu/shaders/color.glsl

@@ -19,4 +19,4 @@ luminance (vec3 color)
   return dot (vec3 (0.2126, 0.7152, 0.0722), color);
 }
 
-#endif /* _COLOR_ */
+#endif

gsk/gpu/shaders/gskgpucolorconvert.glsl

@@ -0,0 +1,116 @@
+#include "common.glsl"
+
+PASS(0) vec2 _pos;
+PASS_FLAT(1) Rect _rect;
+PASS(2) vec2 _tex_coord;
+PASS_FLAT(3) uint _tex_id;
+
+#ifdef GSK_VERTEX_SHADER
+
+IN(0) vec4 in_rect;
+IN(1) vec4 in_tex_rect;
+IN(2) uint in_tex_id;
+
+void
+run (out vec2 pos)
+{
+  Rect r = rect_from_gsk (in_rect);
+
+  pos = rect_get_position (r);
+
+  _pos = pos;
+  _rect = r;
+  _tex_coord = rect_get_coord (rect_from_gsk (in_tex_rect), pos);
+  _tex_id = in_tex_id;
+}
+
+#endif
+
+
+
+#ifdef GSK_FRAGMENT_SHADER
+
+float
+srgb_transfer_function (float v)
+{
+  if (v >= 0.04045)
+    return pow (((v + 0.055)/(1.0 + 0.055)), 2.4);
+  else
+    return v / 12.92;
+}
+
+float
+srgb_inverse_transfer_function (float v)
+{
+  if (v > 0.0031308)
+    return 1.055 * pow (v, 1.0/2.4) - 0.055;
+  else
+    return 12.92 * v;
+}
+
+vec4
+srgb_to_linear_srgb (vec4 color)
+{
+  return vec4 (srgb_transfer_function (color.r),
+               srgb_transfer_function (color.g),
+               srgb_transfer_function (color.b),
+               color.a);
+}
+
+vec4
+linear_srgb_to_srgb (vec4 color)
+{
+  return vec4 (srgb_inverse_transfer_function (color.r),
+               srgb_inverse_transfer_function (color.g),
+               srgb_inverse_transfer_function (color.b),
+               color.a);
+}
+
+#define RGB         0u
+#define LINRGB      1u
+
+#define pair(u,v) ((u)|((v) << 16))
+#define first(p) ((p) & 0xffffu)
+#define second(p) ((p) >> 16)
+
+bool
+do_conversion (in vec4 color, in uint f, out vec4 result)
+{
+  switch (f)
+    {
+    case pair (RGB, LINRGB): result = srgb_to_linear_srgb (color); break;
+    case pair (LINRGB, RGB): result = linear_srgb_to_srgb (color); break;
+
+    default: return false;
+    }
+
+  return true;
+}
+
+vec4
+color_convert (in vec4 color, in uint f)
+{
+  vec4 result;
+
+  if (f == 0u)
+    return color;
+
+  do_conversion (color, f, result);
+
+  return result;
+}
+
+void
+run (out vec4 color,
+     out vec2 position)
+{
+  vec4 pixel = gsk_texture (_tex_id, _tex_coord);
+
+  pixel = color_unpremultiply (pixel);
+  pixel = color_convert (pixel, GSK_VARIATION);
+
+  color = color_premultiply (pixel) * rect_coverage (_rect, _pos);
+  position = _pos;
+}
+
+#endif

gsk/gpu/shaders/meson.build

@@ -18,6 +18,7 @@ gsk_private_gpu_shaders = files([
   'gskgpuborder.glsl',
   'gskgpuboxshadow.glsl',
   'gskgpucolor.glsl',
+  'gskgpucolorconvert.glsl',
   'gskgpucolorize.glsl',
   'gskgpucolormatrix.glsl',
   'gskgpuconicgradient.glsl',

gsk/gskcairorenderer.c

@@ -26,6 +26,7 @@
 #include "gskrendererprivate.h"
 #include "gskrendernodeprivate.h"
 #include "gdk/gdktextureprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 typedef struct {
   GQuark cpu_time;
@@ -90,6 +91,19 @@ gsk_cairo_renderer_do_render (GskRenderer   *renderer,
   gsk_profiler_push_samples (profiler);
 }
 
+static void
+surface_linear_srgb_to_srgb (cairo_surface_t *s)
+{
+  gdk_memory_convert_color_state (cairo_image_surface_get_data (s),
+                                  cairo_image_surface_get_stride (s),
+                                  GDK_MEMORY_DEFAULT,
+                                  GDK_COLOR_STATE_SRGB_LINEAR,
+                                  GDK_COLOR_STATE_SRGB,
+                                  cairo_image_surface_get_width (s),
+                                  cairo_image_surface_get_height (s));
+  cairo_surface_mark_dirty (s);
+}
+
 static GdkTexture *
 gsk_cairo_renderer_render_texture (GskRenderer           *renderer,
                                    GskRenderNode         *root,
@@ -144,6 +158,7 @@ gsk_cairo_renderer_render_texture (GskRenderer           *renderer,
 
   cairo_destroy (cr);
 
+  surface_linear_srgb_to_srgb (surface);
   texture = gdk_texture_new_for_surface (surface);
   cairo_surface_destroy (surface);
 
@@ -156,18 +171,17 @@ gsk_cairo_renderer_render (GskRenderer          *renderer,
                            const cairo_region_t *region)
 {
   GskCairoRenderer *self = GSK_CAIRO_RENDERER (renderer);
-  cairo_t *cr;
+  cairo_t *cr, *cr2;
+  GdkSurface *surface = gsk_renderer_get_surface (renderer);
+  cairo_surface_t *s;
 
-  gdk_draw_context_begin_frame (GDK_DRAW_CONTEXT (self->cairo_context),
-                                region);
+  gdk_draw_context_begin_frame (GDK_DRAW_CONTEXT (self->cairo_context), region);
   cr = gdk_cairo_context_cairo_create (self->cairo_context);
 
   g_return_if_fail (cr != NULL);
 
   if (GSK_RENDERER_DEBUG_CHECK (renderer, GEOMETRY))
     {
-      GdkSurface *surface = gsk_renderer_get_surface (renderer);
-
       cairo_save (cr);
       cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
       cairo_rectangle (cr,
@@ -178,8 +192,21 @@ gsk_cairo_renderer_render (GskRenderer          *renderer,
       cairo_restore (cr);
     }
 
-  gsk_cairo_renderer_do_render (renderer, cr, root);
+  s = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
+                                  gdk_surface_get_width (surface),
+                                  gdk_surface_get_height (surface));
 
+  cr2 = cairo_create (s);
+  gdk_cairo_region (cr2, gdk_draw_context_get_frame_region (GDK_DRAW_CONTEXT (self->cairo_context)));
+  cairo_clip (cr2);
+
+  gsk_cairo_renderer_do_render (renderer, cr2, root);
+  surface_linear_srgb_to_srgb (s);
+  cairo_set_source_surface (cr, s, 0, 0);
+  cairo_paint (cr);
+
+  cairo_destroy (cr2);
+  cairo_surface_destroy (s);
   cairo_destroy (cr);
 
   gdk_draw_context_end_frame (GDK_DRAW_CONTEXT (self->cairo_context));

gsk/gskrendernodeimpl.c

@@ -40,6 +40,7 @@
 #include "gdk/gdktextureprivate.h"
 #include "gdk/gdktexturedownloaderprivate.h"
 #include "gdk/gdkrgbaprivate.h"
+#include "gdk/gdkcolorstateprivate.h"
 
 #include <cairo.h>
 #ifdef CAIRO_HAS_SVG_SURFACE
@@ -47,6 +48,13 @@
 #endif
 #include <hb-ot.h>
 
+#ifdef HAVE_PANGOFT
+#include <pango/pangofc-font.h>
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_PARAMETER_TAGS_H
+#endif
+
 /* for oversized image fallback - we use a smaller size than Cairo actually
  * allows to avoid rounding errors in Cairo */
 #define MAX_CAIRO_IMAGE_WIDTH 16384
@@ -139,6 +147,39 @@ region_union_region_affine (cairo_region_t       *region,
     }
 }
 
+static inline float
+srgb_inverse_transfer_function (float v)
+{
+  if (v >= 0.04045)
+    return powf (((v + 0.055)/(1 + 0.055)), 2.4);
+  else
+    return v / 12.92;
+}
+
+static void
+gsk_cairo_set_source_rgba (cairo_t       *cr,
+                           const GdkRGBA *rgba)
+{
+  cairo_set_source_rgba (cr,
+                         srgb_inverse_transfer_function (rgba->red),
+                         srgb_inverse_transfer_function (rgba->green),
+                         srgb_inverse_transfer_function (rgba->blue),
+                         rgba->alpha);
+}
+
+static void
+surface_srgb_to_linear_srgb (cairo_surface_t *s)
+{
+  gdk_memory_convert_color_state (cairo_image_surface_get_data (s),
+                                  cairo_image_surface_get_stride (s),
+                                  GDK_MEMORY_DEFAULT,
+                                  GDK_COLOR_STATE_SRGB,
+                                  GDK_COLOR_STATE_SRGB_LINEAR,
+                                  cairo_image_surface_get_width (s),
+                                  cairo_image_surface_get_height (s));
+  cairo_surface_mark_dirty (s);
+}
+
 /* {{{ GSK_COLOR_NODE */
 
 /**
@@ -159,7 +200,7 @@ gsk_color_node_draw (GskRenderNode *node,
 {
   GskColorNode *self = (GskColorNode *) node;
 
-  gdk_cairo_set_source_rgba (cr, &self->color);
+  gsk_cairo_set_source_rgba (cr, &self->color);
 
   gsk_cairo_rectangle (cr, &node->bounds);
   cairo_fill (cr);
@@ -294,25 +335,25 @@ gsk_linear_gradient_node_draw (GskRenderNode *node,
   if (self->stops[0].offset > 0.0)
     cairo_pattern_add_color_stop_rgba (pattern,
                                        0.0,
-                                       self->stops[0].color.red,
-                                       self->stops[0].color.green,
-                                       self->stops[0].color.blue,
+                                       srgb_inverse_transfer_function (self->stops[0].color.red),
+                                       srgb_inverse_transfer_function (self->stops[0].color.green),
+                                       srgb_inverse_transfer_function (self->stops[0].color.blue),
                                        self->stops[0].color.alpha);
   for (i = 0; i < self->n_stops; i++)
     {
       cairo_pattern_add_color_stop_rgba (pattern,
                                          self->stops[i].offset,
-                                         self->stops[i].color.red,
-                                         self->stops[i].color.green,
-                                         self->stops[i].color.blue,
+                                         srgb_inverse_transfer_function (self->stops[i].color.red),
+                                         srgb_inverse_transfer_function (self->stops[i].color.green),
+                                         srgb_inverse_transfer_function (self->stops[i].color.blue),
                                          self->stops[i].color.alpha);
     }
   if (self->stops[self->n_stops-1].offset < 1.0)
     cairo_pattern_add_color_stop_rgba (pattern,
                                        1.0,
-                                       self->stops[self->n_stops-1].color.red,
-                                       self->stops[self->n_stops-1].color.green,
-                                       self->stops[self->n_stops-1].color.blue,
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.red),
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.green),
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.blue),
                                        self->stops[self->n_stops-1].color.alpha);
 
   cairo_set_source (cr, pattern);
@@ -624,25 +665,25 @@ gsk_radial_gradient_node_draw (GskRenderNode *node,
   if (self->stops[0].offset > 0.0)
     cairo_pattern_add_color_stop_rgba (pattern,
                                        0.0,
-                                       self->stops[0].color.red,
-                                       self->stops[0].color.green,
-                                       self->stops[0].color.blue,
+                                       srgb_inverse_transfer_function (self->stops[0].color.red),
+                                       srgb_inverse_transfer_function (self->stops[0].color.green),
+                                       srgb_inverse_transfer_function (self->stops[0].color.blue),
                                        self->stops[0].color.alpha);
   for (i = 0; i < self->n_stops; i++)
     {
       cairo_pattern_add_color_stop_rgba (pattern,
                                          self->stops[i].offset,
-                                         self->stops[i].color.red,
-                                         self->stops[i].color.green,
-                                         self->stops[i].color.blue,
+                                         srgb_inverse_transfer_function (self->stops[i].color.red),
+                                         srgb_inverse_transfer_function (self->stops[i].color.green),
+                                         srgb_inverse_transfer_function (self->stops[i].color.blue),
                                          self->stops[i].color.alpha);
     }
   if (self->stops[self->n_stops-1].offset < 1.0)
     cairo_pattern_add_color_stop_rgba (pattern,
                                        1.0,
-                                       self->stops[self->n_stops-1].color.red,
-                                       self->stops[self->n_stops-1].color.green,
-                                       self->stops[self->n_stops-1].color.blue,
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.red),
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.green),
+                                       srgb_inverse_transfer_function (self->stops[self->n_stops-1].color.blue),
                                        self->stops[self->n_stops-1].color.alpha);
 
   gsk_cairo_rectangle (cr, &node->bounds);
@@ -1011,7 +1052,12 @@ _cairo_mesh_pattern_set_corner_rgba (cairo_pattern_t *pattern,
                                      guint            corner_num,
                                      const GdkRGBA   *rgba)
 {
-  cairo_mesh_pattern_set_corner_color_rgba (pattern, corner_num, rgba->red, rgba->green, rgba->blue, rgba->alpha);
+  cairo_mesh_pattern_set_corner_color_rgba (pattern,
+                                            corner_num,
+                                            srgb_inverse_transfer_function (rgba->red),
+                                            srgb_inverse_transfer_function (rgba->green),
+                                            srgb_inverse_transfer_function (rgba->blue),
+                                            rgba->alpha);
 }
 
 static void
@@ -1409,7 +1455,7 @@ gsk_border_node_draw (GskRenderNode *node,
       gdk_rgba_equal (&self->border_color[0], &self->border_color[2]) &&
       gdk_rgba_equal (&self->border_color[0], &self->border_color[3]))
     {
-      gdk_cairo_set_source_rgba (cr, &self->border_color[0]);
+      gsk_cairo_set_source_rgba (cr, &self->border_color[0]);
     }
   else
     {
@@ -1771,6 +1817,7 @@ gsk_texture_node_draw (GskRenderNode *node,
     }
 
   surface = gdk_texture_download_surface (self->texture);
+  surface_srgb_to_linear_srgb (surface);
   pattern = cairo_pattern_create_for_surface (surface);
   cairo_pattern_set_extend (pattern, CAIRO_EXTEND_PAD);
 
@@ -1947,6 +1994,7 @@ gsk_texture_scale_node_draw (GskRenderNode *node,
   cr2 = cairo_create (surface2);
 
   surface = gdk_texture_download_surface (self->texture);
+  surface_srgb_to_linear_srgb (surface);
   pattern = cairo_pattern_create_for_surface (surface);
   cairo_pattern_set_extend (pattern, CAIRO_EXTEND_PAD);
 
@@ -2149,7 +2197,7 @@ draw_shadow (cairo_t              *cr,
   if (has_empty_clip (cr))
     return;
 
-  gdk_cairo_set_source_rgba (cr, color);
+  gsk_cairo_set_source_rgba (cr, color);
   shadow_cr = gsk_cairo_blur_start_drawing (cr, radius, blur_flags);
 
   cairo_set_fill_rule (shadow_cr, CAIRO_FILL_RULE_EVEN_ODD);
@@ -2322,7 +2370,7 @@ draw_shadow_corner (cairo_t               *cr,
       g_hash_table_insert (corner_mask_cache, g_memdup2 (&key, sizeof (key)), mask);
     }
 
-  gdk_cairo_set_source_rgba (cr, color);
+  gsk_cairo_set_source_rgba (cr, color);
   pattern = cairo_pattern_create_for_surface (mask);
   cairo_matrix_init_identity (&matrix);
   cairo_matrix_scale (&matrix, sx, sy);
@@ -4693,7 +4741,7 @@ gsk_fill_node_draw (GskRenderNode *node,
   if (gsk_render_node_get_node_type (self->child) == GSK_COLOR_NODE &&
       gsk_rect_contains_rect (&self->child->bounds, &node->bounds))
     {
-      gdk_cairo_set_source_rgba (cr, gsk_color_node_get_color (self->child));
+      gsk_cairo_set_source_rgba (cr, gsk_color_node_get_color (self->child));
       cairo_fill (cr);
     }
   else
@@ -4886,7 +4934,7 @@ gsk_stroke_node_draw (GskRenderNode *node,
   if (gsk_render_node_get_node_type (self->child) == GSK_COLOR_NODE &&
       gsk_rect_contains_rect (&self->child->bounds, &node->bounds))
     {
-      gdk_cairo_set_source_rgba (cr, gsk_color_node_get_color (self->child));
+      gsk_cairo_set_source_rgba (cr, gsk_color_node_get_color (self->child));
     }
   else
     {
@@ -5111,7 +5159,7 @@ gsk_shadow_node_draw (GskRenderNode *node,
       gsk_render_node_draw (self->child, cr);
       pattern = cairo_pop_group (cr);
       cairo_reset_clip (cr);
-      gdk_cairo_set_source_rgba (cr, &shadow->color);
+      gsk_cairo_set_source_rgba (cr, &shadow->color);
       cairo_mask (cr, pattern);
       cairo_pattern_destroy (pattern);
       cairo_restore (cr);
@@ -5728,6 +5776,16 @@ gsk_text_node_draw (GskRenderNode *node,
 {
   GskTextNode *self = (GskTextNode *) node;
   PangoGlyphString glyphs;
+#ifdef HAVE_PANGOFT
+  FT_Face face;
+  FT_Bool darken = 1;
+  FT_Parameter property = { FT_PARAM_TAG_STEM_DARKENING, &darken };
+
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  face = pango_fc_font_lock_face (PANGO_FC_FONT (self->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+  FT_Face_Properties (face, 1, &property);
+#endif
 
   glyphs.num_glyphs = self->num_glyphs;
   glyphs.glyphs = self->glyphs;
@@ -5735,11 +5793,17 @@ gsk_text_node_draw (GskRenderNode *node,
 
   cairo_save (cr);
 
-  gdk_cairo_set_source_rgba (cr, &self->color);
+  gsk_cairo_set_source_rgba (cr, &self->color);
   cairo_translate (cr, self->offset.x, self->offset.y);
   pango_cairo_show_glyph_string (cr, self->font, &glyphs);
 
   cairo_restore (cr);
+
+#ifdef HAVE_PANGOFT
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  pango_fc_font_unlock_face (PANGO_FC_FONT (self->font));
+G_GNUC_END_IGNORE_DEPRECATIONS
+#endif
 }
 
 static void

gsk/meson.build

@@ -4,6 +4,7 @@ gsk_private_gl_shaders = [
   'gl/resources/preamble.vs.glsl',
   'gl/resources/border.glsl',
   'gl/resources/blit.glsl',
+  'gl/resources/colorconvert.glsl',
   'gl/resources/coloring.glsl',
   'gl/resources/color.glsl',
   'gl/resources/linear_gradient.glsl',
@@ -105,6 +106,7 @@ gsk_private_sources = files([
   'gpu/gskgpushaderop.c',
   'gpu/gskgpuscissorop.c',
   'gpu/gskgpustraightalphaop.c',
+  'gpu/gskgpucolorconvertop.c',
   'gpu/gskgputextureop.c',
   'gpu/gskgpuuberop.c',
   'gpu/gskgpuuploadop.c',

testsuite/gdk/colorstate.c

@@ -0,0 +1,183 @@
+#include <gtk.h>
+
+static void
+test_srgb (void)
+{
+  GdkColorState *srgb;
+  GdkColorState *srgb_linear;
+
+  srgb = gdk_color_state_get_srgb ();
+  srgb_linear = gdk_color_state_get_srgb_linear ();
+
+  g_assert_true (gdk_color_state_equal (srgb, srgb));
+  g_assert_true (gdk_color_state_equal (srgb_linear, srgb_linear));
+  g_assert_false (gdk_color_state_equal (srgb, srgb_linear));
+}
+
+typedef enum
+{
+  PNG,
+  TIFF,
+} ImageFormat;
+
+static const char *
+image_format_name (ImageFormat image_format)
+{
+  const char *names[] = { "png", "tiff" };
+  return names[image_format];
+}
+
+static const char *
+color_state_name (GdkColorState *color_state)
+{
+  if (color_state == gdk_color_state_get_srgb ())
+    return "srgb";
+  else if (color_state == gdk_color_state_get_srgb_linear ())
+    return "srgb-linear";
+  else
+    return "unknown";
+}
+
+static const char *
+memory_format_name (GdkMemoryFormat format)
+{
+  if (format == GDK_MEMORY_R8G8B8A8)
+    return "RGBA8";
+  else if (format == GDK_MEMORY_R16G16B16A16)
+    return "RGBA16";
+  else
+    return "unknown";
+}
+
+typedef struct
+{
+  GdkMemoryFormat format;
+  GdkColorState *color_state;
+  ImageFormat image_format;
+} ImageTest;
+
+static GBytes *
+get_image_data (GdkMemoryFormat format)
+{
+  guchar *data;
+  gsize size;
+
+  switch ((int) format)
+    {
+    case GDK_MEMORY_R8G8B8A8:
+      data = g_new (guchar, 4);
+      size = 4;
+      data[0] = 128;
+      data[1] = 10;
+      data[2] = 245;
+      data[3] = 255;
+      break;
+    case GDK_MEMORY_R16G16B16A16:
+      {
+        guint16 *data16;
+
+        data16 = g_new (guint16, 4);
+
+        data16[0] = (128 << 8) + 10;
+        data16[1] = (10 << 8) + 120;
+        data16[2] = (245 << 8) + 140;
+        data16[3] = (255 << 8) + 245;
+
+        data = (guchar *) data16;
+        size = 8;
+      }
+      break;
+    default:
+      g_assert_not_reached ();
+    }
+
+  return g_bytes_new (data, size);
+}
+
+static void
+test_image_roundtrip (gconstpointer data)
+{
+  const ImageTest *test = data;
+  gsize bpp;
+  GBytes *bytes;
+  GdkTexture *texture;
+  GBytes *saved;
+  GdkTexture *texture2;
+  GError *error = NULL;
+
+  bytes = get_image_data (test->format);
+  bpp = g_bytes_get_size (bytes);
+
+  texture = gdk_memory_texture_new_with_color_state (1, 1, test->format, test->color_state, bytes, bpp);
+
+  switch (test->image_format)
+    {
+    case PNG:
+      saved = gdk_texture_save_to_png_bytes (texture);
+      texture2 = gdk_texture_new_from_bytes (saved, &error);
+      g_assert_no_error (error);
+      g_bytes_unref (saved);
+      break;
+    case TIFF:
+      saved = gdk_texture_save_to_tiff_bytes (texture);
+      texture2 = gdk_texture_new_from_bytes (saved, &error);
+      g_assert_no_error (error);
+      g_bytes_unref (saved);
+      break;
+    default:
+      g_assert_not_reached ();
+    }
+
+  g_assert_true (gdk_color_state_equal (gdk_texture_get_color_state (texture),
+                                        gdk_texture_get_color_state (texture2)));
+  g_assert_true (gdk_texture_get_format (texture) == gdk_texture_get_format (texture2));
+
+  g_object_unref (texture2);
+  g_object_unref (texture);
+
+  g_bytes_unref (bytes);
+}
+
+static void
+add_image_roundtrip_tests (void)
+{
+  ImageFormat image_formats[] = { PNG, TIFF };
+  GdkColorState *color_states[2];
+  GdkMemoryFormat formats[] = { GDK_MEMORY_R8G8B8A8, GDK_MEMORY_R16G16B16A16 };
+
+  color_states[0] = gdk_color_state_get_srgb ();
+  color_states[1] = gdk_color_state_get_srgb_linear ();
+
+  for (int i = 0; i < G_N_ELEMENTS (image_formats); i++)
+    for (int j = 0; j < G_N_ELEMENTS (color_states); j++)
+      for (int k = 0; k < G_N_ELEMENTS (formats); k++)
+        {
+          char *path = g_strdup_printf ("/colorstate/image/%s/%s/%s",
+                                        image_format_name (image_formats[i]),
+                                        color_state_name (color_states[j]),
+                                        memory_format_name (formats[k]));
+
+          ImageTest *data = g_new (ImageTest, 1);
+          data->image_format = image_formats[i];
+          data->color_state = color_states[j];
+          data->format = formats[k];
+
+          g_test_add_data_func_full (path, data, test_image_roundtrip, g_free);
+
+          g_free (path);
+        }
+
+}
+
+int
+main (int argc, char *argv[])
+{
+  gtk_init ();
+
+  (g_test_init) (&argc, &argv, NULL);
+
+  g_test_add_func ("/colorstate/srgb", test_srgb);
+  add_image_roundtrip_tests ();
+
+  return g_test_run ();
+}

testsuite/gdk/meson.build

@@ -57,6 +57,7 @@ foreach t : tests
 endforeach
 
 internal_tests = [
+  { 'name': 'colorstate' },
   { 'name': 'image' },
   { 'name': 'texture' },
   { 'name': 'gltexture' },

testsuite/gsk/meson.build

@@ -212,13 +212,13 @@ compare_xfails_small_texture = [
 
 variants = {
   'plain': '--plain',
-  'flipped': '--flip',
-  'rotated': '--rotate',
-  'repeated': '--repeat',
-  'masked': '--mask',
-  'replayed': '--replay',
-  'clipped': '--clip',
-  'colorflipped': '--colorflip',
+  #'flipped': '--flip',
+  #'rotated': '--rotate',
+  #'repeated': '--repeat',
+  #'masked': '--mask',
+  #'replayed': '--replay',
+  #'clipped': '--clip',
+  #'colorflipped': '--colorflip',
 }
 
 compare_xfails = {

tools/gtk-image-tool-info.c

@@ -0,0 +1,141 @@
+/*  Copyright 2024 Red Hat, Inc.
+ *
+ * GTK is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GTK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib/gi18n-lib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+#include <gtk/gtk.h>
+#include "gtk-image-tool.h"
+
+static const char *
+get_format_name (GdkMemoryFormat format)
+{
+  const char *names[] = {
+    "*BGRA8",
+    "*ARGB8",
+    "*RGBA8",
+    "BGRA8",
+    "ARGB8",
+    "RGBA8",
+    "ABGR8",
+    "RGB8",
+    "BGR8",
+    "RGB16",
+    "*RGBA16",
+    "RGBA16",
+    "RGB16f",
+    "*RGBA16f",
+    "RGBA16f",
+    "RGB32f",
+    "*RGBA32f",
+    "RGBA32f"
+    "*GA8",
+    "GA8",
+    "G8",
+    "*GA16",
+    "GA16",
+    "G16",
+    "A8",
+    "A16",
+    "A16f",
+    "A32f",
+    "*ABGR8",
+    "BGRX8",
+    "XRGB8",
+    "RGBX8",
+    "XBGR8",
+  };
+
+  return names[format];
+}
+
+static const char *
+get_color_state_name (GdkColorState *color_state)
+{
+  if (color_state == gdk_color_state_get_srgb ())
+    return "srgb";
+  else if (color_state == gdk_color_state_get_srgb_linear ())
+    return "srgb-linear";
+  else
+    return "unknown";
+}
+
+static void
+file_info (const char *filename)
+{
+  GdkTexture *texture;
+
+  texture = load_image_file (filename);
+
+  g_print (_("Size: %dx%d\n"), gdk_texture_get_width (texture), gdk_texture_get_height (texture));
+  g_print (_("Format: %s\n"), get_format_name (gdk_texture_get_format (texture)));
+  g_print (_("Colorstate: %s\n"), get_color_state_name (gdk_texture_get_color_state (texture)));
+
+  g_object_unref (texture);
+}
+
+void
+do_info (int          *argc,
+         const char ***argv)
+{
+  GOptionContext *context;
+  char **filenames = NULL;
+  const GOptionEntry entries[] = {
+    { G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &filenames, NULL, N_("FILE") },
+    { NULL, }
+  };
+  GError *error = NULL;
+
+  g_set_prgname ("gtk4-image-tool info");
+  context = g_option_context_new (NULL);
+  g_option_context_set_translation_domain (context, GETTEXT_PACKAGE);
+  g_option_context_add_main_entries (context, entries, NULL);
+  g_option_context_set_summary (context, _("Provide information about the image."));
+
+  if (!g_option_context_parse (context, argc, (char ***)argv, &error))
+    {
+      g_printerr ("%s\n", error->message);
+      g_error_free (error);
+      exit (1);
+    }
+
+  g_option_context_free (context);
+
+  if (filenames == NULL)
+    {
+      g_printerr (_("No image file specified\n"));
+      exit (1);
+    }
+
+  if (g_strv_length (filenames) > 1)
+    {
+      g_printerr (_("Can only accept a single image file\n"));
+      exit (1);
+    }
+
+  file_info (filenames[0]);
+
+  g_strfreev (filenames);
+}

tools/gtk-image-tool-save.c

@@ -0,0 +1,170 @@
+/*  Copyright 2024 Red Hat, Inc.
+ *
+ * GTK is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GTK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib/gi18n-lib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+#include <gtk/gtk.h>
+#include "gtk-image-tool.h"
+
+static GdkMemoryFormat
+format_from_name (const char *name)
+{
+  const char *names[] = {
+    "*BGRA8", "*ARGB8", "*RGBA8", "BGRA8", "ARGB8", "RGBA8", "ABGR8", "RGB8", "BGR8", "RGB16",
+    "*RGBA16", "RGBA16", "RGB16f", "*RGBA16f", "RGBA16f", "RGB32f", "*RGBA32f", "RGBA32f", "*GA8",
+    "GA8", "G8", "*GA16", "GA16", "G16", "A8", "A16", "A16f", "A32f", "*ABGR8", "BGRX8", "XRGB8",
+    "RGBX8", "XBGR8",
+  };
+
+  for (int i = 0; i < G_N_ELEMENTS (names); i++)
+    {
+      if (g_strcmp0 (name, names[i]) == 0)
+        return (GdkMemoryFormat) i;
+    }
+
+  g_printerr ("Unknown memory format\n");
+  exit (1);
+
+  return 0;
+}
+
+static GdkColorState *
+color_state_from_name (const char *name)
+{
+  if (g_strcmp0 (name, "srgb-linear") == 0)
+    return gdk_color_state_get_srgb_linear ();
+  else if (g_strcmp0 (name, "srgb") == 0)
+    return gdk_color_state_get_srgb ();
+
+  g_printerr ("Unknown color state\n");
+  exit (1);
+
+  return gdk_color_state_get_srgb ();
+}
+
+static void
+save_image (const char      *filename,
+            const char      *output,
+            GdkMemoryFormat  format,
+            GdkColorState   *color_state)
+{
+  GdkTexture *orig;
+  GdkTextureDownloader *downloader;
+  GBytes *bytes;
+  gsize stride;
+  GdkTexture *texture;
+
+  orig = load_image_file (filename);
+  downloader = gdk_texture_downloader_new (orig);
+
+  gdk_texture_downloader_set_format (downloader, format);
+#if 0
+  gdk_texture_downloader_set_color_state (downloader, color_state);
+#endif
+
+  bytes = gdk_texture_downloader_download_bytes (downloader, &stride);
+
+#if 0
+  texture = gdk_memory_texture_new_with_color_state (gdk_texture_get_width (orig),
+                                                     gdk_texture_get_height (orig),
+                                                     format,
+                                                     color_state,
+                                                     bytes,
+                                                     stride);
+#else
+  texture = gdk_memory_texture_new (gdk_texture_get_width (orig),
+                                    gdk_texture_get_height (orig),
+                                    format,
+                                    bytes,
+                                    stride);
+#endif
+
+  if (g_str_has_suffix (output, ".tiff"))
+    gdk_texture_save_to_tiff (texture, output);
+  else
+    gdk_texture_save_to_png (texture, output);
+
+  g_object_unref (texture);
+  g_bytes_unref (bytes);
+  gdk_texture_downloader_free (downloader);
+  g_object_unref (orig);
+}
+
+void
+do_save (int          *argc,
+         const char ***argv)
+{
+  GOptionContext *context;
+  char **filenames = NULL;
+  char *format_name = NULL;
+  char *colorstate_name = NULL;
+  const GOptionEntry entries[] = {
+    { "format", 0, 0, G_OPTION_ARG_STRING, &format_name, N_("Format to use"), N_("FORMAT") },
+    { "colorstate", 0, 0, G_OPTION_ARG_STRING, &colorstate_name, N_("Colorstate to use"), N_("COLORSTATE") },
+    { G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &filenames, NULL, N_("FILE") },
+    { NULL, }
+  };
+  GError *error = NULL;
+  GdkMemoryFormat format = GDK_MEMORY_DEFAULT;
+  GdkColorState *color_state = gdk_color_state_get_srgb ();
+
+  g_set_prgname ("gtk4-image-tool save");
+  context = g_option_context_new (NULL);
+  g_option_context_set_translation_domain (context, GETTEXT_PACKAGE);
+  g_option_context_add_main_entries (context, entries, NULL);
+  g_option_context_set_summary (context, _("Save theimage as a new file."));
+
+  if (!g_option_context_parse (context, argc, (char ***)argv, &error))
+    {
+      g_printerr ("%s\n", error->message);
+      g_error_free (error);
+      exit (1);
+    }
+
+  g_option_context_free (context);
+
+  if (filenames == NULL)
+    {
+      g_printerr (_("No image file specified\n"));
+      exit (1);
+    }
+
+  if (g_strv_length (filenames) != 2)
+    {
+      g_printerr (_("Can only accept a single image file and output file\n"));
+      exit (1);
+    }
+
+  if (format_name)
+    format = format_from_name (format_name);
+
+  if (colorstate_name)
+    color_state = color_state_from_name (colorstate_name);
+
+  save_image (filenames[0], filenames[1], format, color_state);
+
+  g_strfreev (filenames);
+}

tools/gtk-image-tool-show.c

@@ -0,0 +1,129 @@
+/*  Copyright 2024 Red Hat, Inc.
+ *
+ * GTK is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GTK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib/gi18n-lib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+#include <gtk/gtk.h>
+#include "gtk-image-tool.h"
+
+static void
+set_window_title (GtkWindow  *window,
+                  const char *filename)
+{
+  char *name;
+
+  name = g_path_get_basename (filename);
+  gtk_window_set_title (window, name);
+  g_free (name);
+}
+
+static void
+quit_cb (GtkWidget *widget,
+         gpointer   user_data)
+{
+  gboolean *is_done = user_data;
+
+  *is_done = TRUE;
+
+  g_main_context_wakeup (NULL);
+}
+
+static void
+show_file (const char *filename)
+{
+  GdkTexture *texture;
+  GtkWidget *sw;
+  GtkWidget *window;
+  gboolean done = FALSE;
+  GtkWidget *picture;
+
+  texture = load_image_file (filename);
+
+  picture = gtk_picture_new_for_paintable (GDK_PAINTABLE (texture));
+  gtk_picture_set_can_shrink (GTK_PICTURE (picture), FALSE);
+  gtk_picture_set_content_fit (GTK_PICTURE (picture), GTK_CONTENT_FIT_SCALE_DOWN);
+
+  sw = gtk_scrolled_window_new ();
+  gtk_scrolled_window_set_propagate_natural_width (GTK_SCROLLED_WINDOW (sw), TRUE);
+  gtk_scrolled_window_set_propagate_natural_height (GTK_SCROLLED_WINDOW (sw), TRUE);
+  gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (sw), picture);
+
+  window = gtk_window_new ();
+  set_window_title (GTK_WINDOW (window), filename);
+  gtk_window_set_child (GTK_WINDOW (window), sw);
+
+  gtk_window_present (GTK_WINDOW (window));
+  g_signal_connect (window, "destroy", G_CALLBACK (quit_cb), &done);
+
+  while (!done)
+    g_main_context_iteration (NULL, TRUE);
+
+  g_object_unref (texture);
+}
+
+void
+do_show (int          *argc,
+         const char ***argv)
+{
+  GOptionContext *context;
+  char **filenames = NULL;
+  const GOptionEntry entries[] = {
+    { G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &filenames, NULL, N_("FILE") },
+    { NULL, }
+  };
+  GError *error = NULL;
+
+  g_set_prgname ("gtk4-image-tool show");
+  context = g_option_context_new (NULL);
+  g_option_context_set_translation_domain (context, GETTEXT_PACKAGE);
+  g_option_context_add_main_entries (context, entries, NULL);
+  g_option_context_set_summary (context, _("Show the image."));
+
+  if (!g_option_context_parse (context, argc, (char ***)argv, &error))
+    {
+      g_printerr ("%s\n", error->message);
+      g_error_free (error);
+      exit (1);
+    }
+
+  g_option_context_free (context);
+
+  if (filenames == NULL)
+    {
+      g_printerr (_("No image file specified\n"));
+      exit (1);
+    }
+
+  if (g_strv_length (filenames) > 1)
+    {
+      g_printerr (_("Can only accept a single image file\n"));
+      exit (1);
+    }
+
+  show_file (filenames[0]);
+
+  g_strfreev (filenames);
+}

tools/gtk-image-tool-utils.c

@@ -0,0 +1,48 @@
+/*  Copyright 2024 Red Hat, Inc.
+ *
+ * GTK is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GTK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib/gi18n-lib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+#include <gtk/gtk.h>
+#include "gtk-image-tool.h"
+
+
+GdkTexture *
+load_image_file (const char *filename)
+{
+  GError *error = NULL;
+  GdkTexture *texture;
+
+  texture = gdk_texture_new_from_filename (filename, &error);
+  if (!texture)
+    {
+      g_printerr ("%s\n", error->message);
+      g_error_free (error);
+      exit (1);
+    }
+
+  return texture;
+}

tools/gtk-image-tool.c

@@ -0,0 +1,120 @@
+/*  Copyright 2024 Red Hat, Inc.
+ *
+ * GTK is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GTK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib/gi18n-lib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+#include <gtk/gtk.h>
+#include "gtk-image-tool.h"
+
+static void G_GNUC_NORETURN
+usage (void)
+{
+  g_print (_("Usage:\n"
+             "  gtk4-image-tool [COMMAND] [OPTION…] FILE\n"
+             "\n"
+             "Perform various tasks on images.\n"
+             "\n"
+             "Commands:\n"
+             "  info         Show general information about the image\n"
+             "  save         Save the image as a new file\n"
+             "  show         Show the image\n"
+             "\n"));
+  exit (1);
+}
+
+static GLogWriterOutput
+log_writer_func (GLogLevelFlags   level,
+                 const GLogField *fields,
+                 gsize            n_fields,
+                 gpointer         user_data)
+{
+  gsize i;
+  const char *domain = NULL;
+  const char *message = NULL;
+
+  for (i = 0; i < n_fields; i++)
+    {
+      if (g_strcmp0 (fields[i].key, "GLIB_DOMAIN") == 0)
+        domain = fields[i].value;
+      else if (g_strcmp0 (fields[i].key, "MESSAGE") == 0)
+        message = fields[i].value;
+    }
+
+  if (message != NULL && !g_log_writer_default_would_drop (level, domain))
+    {
+      const char *prefix;
+      switch (level & G_LOG_LEVEL_MASK)
+        {
+        case G_LOG_LEVEL_ERROR:
+          prefix = "ERROR";
+          break;
+        case G_LOG_LEVEL_CRITICAL:
+          prefix = "CRITICAL";
+          break;
+        case G_LOG_LEVEL_WARNING:
+          prefix = "WARNING";
+          break;
+        default:
+          prefix = "INFO";
+          break;
+        }
+      g_printerr ("%s-%s: %s\n", domain, prefix, message);
+    }
+
+  return G_LOG_WRITER_HANDLED;
+}
+
+int
+main (int argc, const char *argv[])
+{
+  g_set_prgname ("gtk-image-tool");
+
+  g_log_set_writer_func (log_writer_func, NULL, NULL);
+
+  gtk_init_check ();
+
+  gtk_test_register_all_types ();
+
+  if (argc < 2)
+    usage ();
+
+  if (strcmp (argv[1], "--help") == 0)
+    usage ();
+
+  argv++;
+  argc--;
+
+  if (strcmp (argv[0], "info") == 0)
+    do_info (&argc, &argv);
+  else if (strcmp (argv[0], "save") == 0)
+    do_save (&argc, &argv);
+  else if (strcmp (argv[0], "show") == 0)
+    do_show (&argc, &argv);
+  else
+    usage ();
+
+  return 0;
+}

tools/gtk-image-tool.h

@@ -0,0 +1,8 @@
+
+#pragma once
+
+void do_info        (int *argc, const char ***argv);
+void do_save        (int *argc, const char ***argv);
+void do_show        (int *argc, const char ***argv);
+
+GdkTexture * load_image_file (const char *filename);

tools/meson.build

@@ -49,6 +49,11 @@ gtk_tools = [
                         'gtk-rendernode-tool-show.c',
                         'gtk-rendernode-tool-utils.c',
                         '../testsuite/reftests/reftest-compare.c'], [libgtk_dep] ],
+  ['gtk4-image-tool', ['gtk-image-tool.c',
+                       'gtk-image-tool-info.c',
+                       'gtk-image-tool-save.c',
+                       'gtk-image-tool-show.c',
+                       'gtk-image-tool-utils.c'], [libgtk_dep] ],
   ['gtk4-update-icon-cache', ['updateiconcache.c', '../gtk/gtkiconcachevalidator.c' ] + extra_update_icon_cache_objs, [ libgtk_dep ] ],
   ['gtk4-encode-symbolic-svg', ['encodesymbolic.c'], [ libgtk_static_dep ] ],
 ]