Bug 1012407 - Part 1: Reduce amount of data uploaded to GPU (layer quad rect instead of transform) r=Bas

gfx/layers/opengl/OGLShaderProgram.cpp

@@ -32,7 +32,7 @@ AddUniforms(ProgramProfileOGL& aProfile)
     static const char *sKnownUniformNames[] = {
         "uLayerTransform",
         "uMaskQuadTransform",
-        "uLayerQuadTransform",
+        "uLayerQuadRect",
         "uMatrixProj",
         "uTextureTransform",
         "uRenderTargetOffset",
@@ -145,7 +145,7 @@ ProgramProfileOGL::GetProfileFor(ShaderConfigOGL aConfig)
   AddUniforms(result);
 
   vs << "uniform mat4 uMatrixProj;" << endl;
-  vs << "uniform mat4 uLayerQuadTransform;" << endl;
+  vs << "uniform vec4 uLayerQuadRect;" << endl;
   vs << "uniform mat4 uLayerTransform;" << endl;
   vs << "uniform vec4 uRenderTargetOffset;" << endl;
 
@@ -164,8 +164,7 @@ ProgramProfileOGL::GetProfileFor(ShaderConfigOGL aConfig)
   }
 
   vs << "void main() {" << endl;
-  vs << "  vec4 finalPosition = aVertexCoord;" << endl;
-  vs << "  finalPosition = uLayerQuadTransform * finalPosition;" << endl;
+  vs << "  vec4 finalPosition = vec4(aVertexCoord.xy * uLayerQuadRect.zw + uLayerQuadRect.xy, 0.0, 1.0);" << endl;
   vs << "  finalPosition = uLayerTransform * finalPosition;" << endl;
   vs << "  finalPosition.xyz /= finalPosition.w;" << endl;
 

gfx/layers/opengl/OGLShaderProgram.h

@@ -52,7 +52,7 @@ public:
 
     LayerTransform = 0,
     MaskQuadTransform,
-    LayerQuadTransform,
+    LayerQuadRect,
     MatrixProj,
     TextureTransform,
     RenderTargetOffset,
@@ -322,21 +322,13 @@ public:
   }
 
   void SetLayerQuadRect(const nsIntRect& aRect) {
-    gfx3DMatrix m;
-    m._11 = float(aRect.width);
-    m._22 = float(aRect.height);
-    m._41 = float(aRect.x);
-    m._42 = float(aRect.y);
-    SetMatrixUniform(KnownUniform::LayerQuadTransform, m);
+    float vals[4] = { float(aRect.x), float(aRect.y), float(aRect.width), float(aRect.height) };
+    SetUniform(KnownUniform::LayerQuadRect, 4, vals);
   }
 
   void SetLayerQuadRect(const gfx::Rect& aRect) {
-    gfx3DMatrix m;
-    m._11 = aRect.width;
-    m._22 = aRect.height;
-    m._41 = aRect.x;
-    m._42 = aRect.y;
-    SetMatrixUniform(KnownUniform::LayerQuadTransform, m);
+    float vals[4] = { float(aRect.x), float(aRect.y), float(aRect.width), float(aRect.height) };
+    SetUniform(KnownUniform::LayerQuadRect, 4, vals);
   }
 
   void SetProjectionMatrix(const gfx::Matrix4x4& aMatrix) {