From 202b4398901332701cb8c230fefdc13f6afbbd89 Mon Sep 17 00:00:00 2001
From: Andreas Gal <gal@mozilla.com>
Date: Wed, 21 May 2014 23:03:49 +0200
Subject: [PATCH] Bug 1012407 - Part 1: Reduce amount of data uploaded to GPU
 (layer quad rect instead of transform) r=Bas

---
 gfx/layers/opengl/OGLShaderProgram.cpp |  7 +++----
 gfx/layers/opengl/OGLShaderProgram.h   | 18 +++++-------------
 2 files changed, 8 insertions(+), 17 deletions(-)

diff --git a/gfx/layers/opengl/OGLShaderProgram.cpp b/gfx/layers/opengl/OGLShaderProgram.cpp
index 5ef580672c61..e77aa6386b5d 100644
--- a/gfx/layers/opengl/OGLShaderProgram.cpp
+++ b/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;
 
diff --git a/gfx/layers/opengl/OGLShaderProgram.h b/gfx/layers/opengl/OGLShaderProgram.h
index 0e3f1980bb4a..c44e3c0bef57 100644
--- a/gfx/layers/opengl/OGLShaderProgram.h
+++ b/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) {