gpu,gpu/gl: implement shader uniform buffers

Emulate them for the OpenGL ES backend because 2.0 doesn't support uniform
buffers. The future d3d backend only supports uniform (constant) buffers.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

gpu/shaders/blit.vert

@@ -10,7 +10,7 @@ layout(binding = 0) uniform Block {
 	vec2 offset;
 	vec2 uvScale;
 	vec2 uvOffset;
-} uniforms;
+};
 
 layout(location = 0) in vec2 pos;
 
@@ -20,8 +20,8 @@ layout(location = 0) out vec2 vUV;
 
 void main() {
 	vec2 p = pos;
-	p *= uniforms.scale;
-	p += uniforms.offset;
-	gl_Position = vec4(p, uniforms.z, 1);
-	vUV = uv*uniforms.uvScale + uniforms.uvOffset;
+	p *= scale;
+	p += offset;
+	gl_Position = vec4(p, z, 1);
+	vUV = uv*uvScale + uvOffset;
 }

gpu/shaders/common.inc

@@ -0,0 +1,4 @@
+#version 310 es
+
+void blah() {
+}

gpu/shaders/cover.vert

@@ -8,11 +8,11 @@ layout(binding = 0) uniform Block {
 	float z;
 	vec2 scale;
 	vec2 offset;
-	vec2 uvScale;
-	vec2 uvOffset;
 	vec2 uvCoverScale;
 	vec2 uvCoverOffset;
-} uniforms;
+	vec2 uvScale;
+	vec2 uvOffset;
+};
 
 layout(location = 0) in vec2 pos;
 
@@ -22,7 +22,7 @@ layout(location = 1) in vec2 uv;
 layout(location = 1) out vec2 vUV;
 
 void main() {
-    gl_Position = vec4(pos*uniforms.scale + uniforms.offset, uniforms.z, 1);
-	vUV = uv*uniforms.uvScale + uniforms.uvOffset;
-	vCoverUV = uv*uniforms.uvCoverScale+uniforms.uvCoverOffset;
+    gl_Position = vec4(pos*scale + offset, z, 1);
+	vUV = uv*uvScale + uvOffset;
+	vCoverUV = uv*uvCoverScale+uvCoverOffset;
 }

gpu/shaders/intersect.vert

@@ -10,7 +10,7 @@ layout(location = 1) in vec2 uv;
 layout(binding = 0) uniform Block {
 	vec2 scale;
 	vec2 offset;
-} uvparams;
+};
 
 layout(location = 0) out vec2 vUV;
 
@@ -18,5 +18,5 @@ void main() {
   vec2 p = pos;
   p.y = -p.y;
   gl_Position = vec4(p, 0, 1);
-  vUV = uv*uvparams.scale + uvparams.offset;
+  vUV = uv*scale + offset;
 }

gpu/shaders/stencil.vert

@@ -8,7 +8,7 @@ layout(binding = 0) uniform Block {
 	vec2 scale;
 	vec2 offset;
 	vec2 pathOffset;
-} uniforms;
+};
 
 layout(location=0) in vec2 corner;
 layout(location=1) in float maxy;
@@ -24,10 +24,10 @@ void main() {
 	// Add a one pixel overlap so curve quads cover their
 	// entire curves. Could use conservative rasterization
 	// if available.
-	vec2 from = from + uniforms.pathOffset;
-	vec2 ctrl = ctrl + uniforms.pathOffset;
-	vec2 to = to + uniforms.pathOffset;
-	float maxy = maxy + uniforms.pathOffset.y;
+	vec2 from = from + pathOffset;
+	vec2 ctrl = ctrl + pathOffset;
+	vec2 to = to + pathOffset;
+	float maxy = maxy + pathOffset.y;
 	vec2 pos;
 	if (corner.x > 0.0) {
 		// East.
@@ -46,8 +46,8 @@ void main() {
 	vFrom = from-pos;
 	vCtrl = ctrl-pos;
 	vTo = to-pos;
-    pos *= uniforms.scale;
-    pos += uniforms.offset;
+    pos *= scale;
+    pos += offset;
     gl_Position = vec4(pos, 1, 1);
 }