gdk: Add GdkGLPixelFormat:stereo

Missing pixel format attribute for stereoscopic buffers.

gdk/gdkglpixelformat.c

@@ -104,6 +104,7 @@ enum {
   /* bool */
   PROP_DOUBLE_BUFFER,
   PROP_MULTI_SAMPLE,
+  PROP_STEREO,
 
   /* uint */
   PROP_AUX_BUFFERS,
@@ -145,6 +146,10 @@ gdk_gl_pixel_format_set_property (GObject      *gobject,
       self->multi_sample = g_value_get_boolean (value);
       break;
 
+    case PROP_STEREO:
+      self->stereo = g_value_get_boolean (value);
+      break;
+
     case PROP_AUX_BUFFERS:
       self->aux_buffers = g_value_get_int (value);
       break;
@@ -204,6 +209,10 @@ gdk_gl_pixel_format_get_property (GObject    *gobject,
       g_value_set_boolean (value, self->multi_sample);
       break;
 
+    case PROP_STEREO:
+      g_value_set_boolean (value, self->stereo);
+      break;
+
     case PROP_AUX_BUFFERS:
       g_value_set_int (value, self->aux_buffers);
       break;
@@ -288,6 +297,22 @@ gdk_gl_pixel_format_class_init (GdkGLPixelFormatClass *klass)
                           G_PARAM_CONSTRUCT_ONLY |
                           G_PARAM_STATIC_STRINGS);
 
+  /**
+   * GdkGLPixelFormat:stereo:
+   *
+   * Whether the pixel format should support stereoscopic buffers.
+   *
+   * Since: 3.14
+   */
+  obj_props[PROP_STEREO] =
+    g_param_spec_boolean ("stereo",
+                          P_("Stereo"),
+                          P_("Whether the pixel format should support stereoscopic buffers"),
+                          FALSE,
+                          G_PARAM_READWRITE |
+                          G_PARAM_CONSTRUCT_ONLY |
+                          G_PARAM_STATIC_STRINGS);
+
   /**
    * GdkGLPixelFormat:aux-buffers:
    *
@@ -518,6 +543,8 @@ GDK_GL_PIXEL_FORMAT_GET (gboolean, double_buffer, FALSE)
 
 GDK_GL_PIXEL_FORMAT_GET (gboolean, multi_sample, FALSE)
 
+GDK_GL_PIXEL_FORMAT_GET (gboolean, stereo, FALSE)
+
 GDK_GL_PIXEL_FORMAT_GET (gint, color_size, 0)
 
 GDK_GL_PIXEL_FORMAT_GET (gint, alpha_size, 0)

gdk/gdkglpixelformatprivate.h

@@ -35,6 +35,7 @@ struct _GdkGLPixelFormat
 
   gboolean double_buffer;
   gboolean multi_sample;
+  gboolean stereo;
 
   int aux_buffers;
   int color_size;

gdk/x11/gdkglcontext-x11.c

@@ -318,6 +318,12 @@ get_glx_attributes_for_pixel_format (GdkDisplay       *display,
       attrs[i++] = GL_TRUE;
     }
 
+  if (format->stereo)
+    {
+      attrs[i++] = GLX_STEREO;
+      attrs[i++] = GL_TRUE;
+    }
+
   if (format->color_size < 0)
     {
       attrs[i++] = GLX_RED_SIZE;