gpu: Turn globals into macros

This way, we can be more flexible in refactoring how we handle globals
(guess what we're gonna do next).

gsk/gpu/gskgpunodeprocessor.c

@@ -46,7 +46,7 @@
  *
  * 3. the scaled coordinate system
  * converts on CPU: NodeProcessor.scale
- * converts on GPU: push.scale
+ * converts on GPU: GSK_GLOBAL_SCALE
  * This includes the current scale of the transform. It is usually equal to the scale factor
  * of the window we are rendering to (which is bad because devs without hidpi screens can
  * forget this and then everyone else will see bugs). We make decisions about pixel sizes in
@@ -65,7 +65,7 @@
  *
  * 5. the GL coordinate system
  * converts on CPU: NodeProcessor.projection
- * converts on GPU: push.mvp (from scaled coordinate system)
+ * converts on GPU: GSK_GLOBAL_MVP (from scaled coordinate system)
  * This coordinate system is what GL (or Vulkan) expect coordinates to appear in, and is usually
  * (-1, -1) => (1, 1), but may be flipped etc depending on the render target. The CPU essentially
  * never uses it, other than to allow the vertex shaders to emit its vertices.

gsk/gpu/shaders/common-gl.glsl

@@ -8,12 +8,15 @@ layout(std140, binding = 0)
 uniform PushConstants
 {
     mat4 mvp;
-    vec4 clip_bounds;
-    vec4 clip_widths;
-    vec4 clip_heights;
+    mat3x4 clip;
     vec2 scale;
 } push;
 
+#define GSK_GLOBAL_MVP push.mvp
+#define GSK_GLOBAL_CLIP push.clip
+#define GSK_GLOBAL_CLIP_RECT push.clip[0]
+#define GSK_GLOBAL_SCALE push.scale
+
 #if defined(GSK_GLES) && __VERSION__ < 310
 layout(std140)
 #else

gsk/gpu/shaders/common-vulkan.glsl

@@ -4,14 +4,17 @@
 
 layout(push_constant) uniform PushConstants {
     mat4 mvp;
-    vec4 clip_bounds;
-    vec4 clip_widths;
-    vec4 clip_heights;
+    mat3x4 clip;
     vec2 scale;
 } push;
 
 layout(constant_id=0) const uint GSK_SHADER_CLIP = GSK_GPU_SHADER_CLIP_NONE;
 
+#define GSK_GLOBAL_MVP push.mvp
+#define GSK_GLOBAL_CLIP push.clip
+#define GSK_GLOBAL_CLIP_RECT push.clip[0]
+#define GSK_GLOBAL_SCALE push.scale
+
 #define GSK_VERTEX_INDEX gl_VertexIndex
 
 #ifdef GSK_VERTEX_SHADER

gsk/gpu/shaders/common.glsl

@@ -25,7 +25,7 @@ rect_clip (Rect r)
   if (GSK_SHADER_CLIP == GSK_GPU_SHADER_CLIP_NONE)
     return r;
   else
-    return rect_intersect (r, rect_from_gsk (push.clip_bounds));
+    return rect_intersect (r, rect_from_gsk (GSK_GLOBAL_CLIP_RECT));
 }
 
 #ifdef GSK_VERTEX_SHADER
@@ -40,7 +40,7 @@ const vec2 offsets[6] = vec2[6](vec2(0.0, 0.0),
 void
 gsk_set_position (vec2 pos)
 {
-  gl_Position = push.mvp * vec4 (pos, 0.0, 1.0);
+  gl_Position = GSK_GLOBAL_MVP * vec4 (pos, 0.0, 1.0);
 }
 
 vec2
@@ -145,7 +145,7 @@ main_clip_rect (void)
 
   run (color, pos);
 
-  Rect clip = rect_from_gsk (push.clip_bounds);
+  Rect clip = rect_from_gsk (GSK_GLOBAL_CLIP_RECT);
 
   float coverage = rect_coverage (clip, pos);
   color *= coverage;
@@ -161,8 +161,7 @@ main_clip_rounded (void)
 
   run (color, pos);
 
-  RoundedRect clip = RoundedRect(vec4(push.clip_bounds.xy, push.clip_bounds.xy + push.clip_bounds.zw), push.clip_widths, push.clip_heights);
-  rounded_rect_scale (clip, push.scale);
+  RoundedRect clip = rounded_rect_from_gsk (GSK_GLOBAL_CLIP);
 
   float coverage = rounded_rect_coverage (clip, pos);
   color *= coverage;

gsk/gpu/shaders/gskgpublur.glsl

@@ -34,8 +34,8 @@ run (out vec2 pos)
   _tex_coord = rect_get_coord (tex_rect, pos);
   _tex_id = in_tex_id;
 
-  float blur_radius = length (push.scale * in_blur_direction);
-  _tex_blur_step = push.scale * in_blur_direction / blur_radius / rect_size (tex_rect);
+  float blur_radius = length (GSK_GLOBAL_SCALE * in_blur_direction);
+  _tex_blur_step = GSK_GLOBAL_SCALE * in_blur_direction / blur_radius / rect_size (tex_rect);
   _samples_per_side = uint (floor (blur_radius));
   float sigma = blur_radius / 2.0;
   _initial_gaussian.x = 1.0 / (sqrt (2.0 * PI) * sigma);

gsk/gpu/shaders/gskgpuborder.glsl

@@ -54,7 +54,7 @@ compute_color (void)
 void
 run (out vec2 pos)
 {
-  vec4 border_widths = in_border_widths * push.scale.yxyx;
+  vec4 border_widths = in_border_widths * GSK_GLOBAL_SCALE.yxyx;
   RoundedRect outside = rounded_rect_from_gsk (in_outline);
   RoundedRect inside = rounded_rect_shrink (outside, border_widths);
   rounded_rect_offset (inside, in_offset);

gsk/gpu/shaders/pattern.glsl

@@ -203,7 +203,7 @@ glyphs_pattern (inout uint reader,
 
       float coverage = rect_coverage (glyph_bounds, pos);
       if (coverage > 0.0)
-        opacity += coverage * gsk_texture (tex_id, (pos - push.scale * tex_rect.xy) / (push.scale * tex_rect.zw)).a;
+        opacity += coverage * gsk_texture (tex_id, (pos - GSK_GLOBAL_SCALE * tex_rect.xy) / (GSK_GLOBAL_SCALE * tex_rect.zw)).a;
     }
 
   return color * opacity;
@@ -216,7 +216,7 @@ texture_pattern (inout uint reader,
   uint tex_id = read_uint (reader);
   vec4 tex_rect = read_vec4 (reader);
 
-  return gsk_texture (tex_id, (pos - push.scale * tex_rect.xy) / (push.scale * tex_rect.zw));
+  return gsk_texture (tex_id, (pos - GSK_GLOBAL_SCALE * tex_rect.xy) / (GSK_GLOBAL_SCALE * tex_rect.zw));
 }
 
 vec4
@@ -224,8 +224,8 @@ linear_gradient_pattern (inout uint reader,
                          vec2       pos,
                          bool       repeating)
 {
-  vec2 start = read_vec2 (reader) * push.scale;
-  vec2 end = read_vec2 (reader) * push.scale;
+  vec2 start = read_vec2 (reader) * GSK_GLOBAL_SCALE;
+  vec2 end = read_vec2 (reader) * GSK_GLOBAL_SCALE;
   Gradient gradient = read_gradient (reader);
 
   vec2 line = end - start;
@@ -244,8 +244,8 @@ radial_gradient_pattern (inout uint reader,
                          vec2       pos,
                          bool       repeating)
 {
-  vec2 center = read_vec2 (reader) * push.scale;
-  vec2 radius = read_vec2 (reader) * push.scale;
+  vec2 center = read_vec2 (reader) * GSK_GLOBAL_SCALE;
+  vec2 radius = read_vec2 (reader) * GSK_GLOBAL_SCALE;
   float start = read_float (reader);
   float end = read_float (reader);
   Gradient gradient = read_gradient (reader);
@@ -269,7 +269,7 @@ conic_gradient_pattern (inout uint reader,
   Gradient gradient = read_gradient (reader);
 
   /* scaling modifies angles, so be sure to use right coordinate system */
-  pos = pos / push.scale - center;
+  pos = pos / GSK_GLOBAL_SCALE - center;
   float offset = atan (pos.y, pos.x);
   offset = degrees (offset + angle) / 360.0;
   float overflow = fract (offset + 0.5);

gsk/gpu/shaders/rect.glsl

@@ -18,7 +18,7 @@ Rect
 rect_from_gsk (vec4 coords)
 {
   Rect result = rect_new_size (coords);
-  result.bounds *= push.scale.xyxy;
+  result.bounds *= GSK_GLOBAL_SCALE.xyxy;
   return result;
 }
 

gsk/gpu/shaders/roundedrect.glsl

@@ -14,9 +14,9 @@ struct RoundedRect
 RoundedRect
 rounded_rect_from_gsk (mat3x4 gsk_rounded_rect)
 {
-  return RoundedRect ((gsk_rounded_rect[0].xyxy + vec4 (0.0, 0.0, gsk_rounded_rect[0].zw)) * push.scale.xyxy,
-                      gsk_rounded_rect[1] * push.scale.xxxx,
-                      gsk_rounded_rect[2] * push.scale.yyyy);
+  return RoundedRect ((gsk_rounded_rect[0].xyxy + vec4 (0.0, 0.0, gsk_rounded_rect[0].zw)) * GSK_GLOBAL_SCALE.xyxy,
+                      gsk_rounded_rect[1] * GSK_GLOBAL_SCALE.xxxx,
+                      gsk_rounded_rect[2] * GSK_GLOBAL_SCALE.yyyy);
 }
 
 float