Revert "cc: Clamp texture coordinates in all tile shaders"

This reverts commit 55e4b3b0.

BUG=173804


Review URL: https://chromiumcodereview.appspot.com/12208140

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182129 0039d316-1c4b-4281-b951-d872f2087c98

cc/gl_renderer.cc

@@ -897,8 +897,18 @@ void GLRenderer::drawTileQuad(const DrawingFrame& frame, const TileDrawQuad* qua
         // We should not DCHECK(!clipped) here, because anti-aliasing inflation may cause deviceQuad to become
         // clipped. To our knowledge this scenario does not need to be handled differently than the unclipped case.
     } else {
+        // Move fragment shader transform to vertex shader. We can do this while
+        // still producing correct results as fragmentTexTransformLocation
+        // should always be non-negative when tiles are transformed in a way
+        // that could result in sampling outside the layer.
+        vertexTexScaleX *= fragmentTexScaleX;
+        vertexTexScaleY *= fragmentTexScaleY;
+        vertexTexTranslateX *= fragmentTexScaleX;
+        vertexTexTranslateY *= fragmentTexScaleY;
+        vertexTexTranslateX += fragmentTexTranslateX;
+        vertexTexTranslateY += fragmentTexTranslateY;
+
         GLC(context(), context()->uniform4f(uniforms.vertexTexTransformLocation, vertexTexTranslateX, vertexTexTranslateY, vertexTexScaleX, vertexTexScaleY));
-        GLC(context(), context()->uniform4f(uniforms.fragmentTexTransformLocation, fragmentTexTranslateX, fragmentTexTranslateY, fragmentTexScaleX, fragmentTexScaleY));
 
         localQuad = gfx::RectF(tileRect);
     }

cc/gl_renderer.h

@@ -144,12 +144,12 @@ private:
     // This block of bindings defines all of the programs used by the compositor itself.
 
     // Tiled layer shaders.
-    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampAlpha> TileProgram;
+    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexAlpha> TileProgram;
     typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampAlphaAA> TileProgramAA;
     typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampSwizzleAlphaAA> TileProgramSwizzleAA;
-    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampOpaque> TileProgramOpaque;
-    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampSwizzleAlpha> TileProgramSwizzle;
-    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexClampSwizzleOpaque> TileProgramSwizzleOpaque;
+    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexOpaque> TileProgramOpaque;
+    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexSwizzleAlpha> TileProgramSwizzle;
+    typedef ProgramBinding<VertexShaderTile, FragmentShaderRGBATexSwizzleOpaque> TileProgramSwizzleOpaque;
     typedef ProgramBinding<VertexShaderPosTex, FragmentShaderCheckerboard> TileCheckerboardProgram;
 
     // Render surface shaders.

cc/shader.cc

@@ -345,31 +345,6 @@ void FragmentTexAlphaBinding::init(WebGraphicsContext3D* context, unsigned progr
     DCHECK(m_samplerLocation != -1 && m_alphaLocation != -1);
 }
 
-FragmentTexClampAlphaBinding::FragmentTexClampAlphaBinding()
-    : m_samplerLocation(-1)
-    , m_alphaLocation(-1)
-    , m_fragmentTexTransformLocation(-1)
-{
-}
-
-void FragmentTexClampAlphaBinding::init(WebGraphicsContext3D* context, unsigned program, bool usingBindUniform, int* baseUniformIndex)
-{
-    static const char* shaderUniforms[] = {
-        "s_texture",
-        "alpha",
-        "fragmentTexTransform",
-    };
-    int locations[3];
-
-    getProgramUniformLocations(context, program, shaderUniforms, arraysize(shaderUniforms), arraysize(locations), locations, usingBindUniform, baseUniformIndex);
-
-    m_samplerLocation = locations[0];
-    m_alphaLocation = locations[1];
-    m_fragmentTexTransformLocation = locations[2];
-    DCHECK(m_samplerLocation != -1 && m_alphaLocation != -1);
-}
-
-
 FragmentTexOpaqueBinding::FragmentTexOpaqueBinding()
     : m_samplerLocation(-1)
 {
@@ -388,27 +363,6 @@ void FragmentTexOpaqueBinding::init(WebGraphicsContext3D* context, unsigned prog
     DCHECK(m_samplerLocation != -1);
 }
 
-FragmentTexClampOpaqueBinding::FragmentTexClampOpaqueBinding()
-    : m_samplerLocation(-1)
-    , m_fragmentTexTransformLocation(-1)
-{
-}
-
-void FragmentTexClampOpaqueBinding::init(WebGraphicsContext3D* context, unsigned program, bool usingBindUniform, int* baseUniformIndex)
-{
-    static const char* shaderUniforms[] = {
-        "s_texture",
-        "fragmentTexTransform",
-    };
-    int locations[2];
-
-    getProgramUniformLocations(context, program, shaderUniforms, arraysize(shaderUniforms), arraysize(locations), locations, usingBindUniform, baseUniformIndex);
-
-    m_samplerLocation = locations[0];
-    m_fragmentTexTransformLocation = locations[1];
-    DCHECK(m_samplerLocation != -1);
-}
-
 std::string FragmentShaderRGBATexFlipVaryingAlpha::getShaderString() const
 {
     return SHADER(
@@ -466,24 +420,6 @@ std::string FragmentShaderRGBATexAlpha::getShaderString() const
     );
 }
 
-std::string FragmentShaderRGBATexClampAlpha::getShaderString() const
-{
-    return SHADER(
-        precision mediump float;
-        varying vec2 v_texCoord;
-        uniform sampler2D s_texture;
-        uniform float alpha;
-        uniform vec4 fragmentTexTransform;
-        void main()
-        {
-            vec2 texCoord = clamp(v_texCoord, 0.0, 1.0) * fragmentTexTransform.zw + fragmentTexTransform.xy;
-            vec4 texColor = texture2D(s_texture, texCoord);
-            gl_FragColor = texColor * alpha;
-        }
-    );
-}
-
-
 std::string FragmentShaderRGBATexVaryingAlpha::getShaderString() const
 {
     return SHADER(
@@ -530,17 +466,15 @@ std::string FragmentShaderRGBATexRectVaryingAlpha::getShaderString() const
             "}\n";
 }
 
-std::string FragmentShaderRGBATexClampOpaque::getShaderString() const
+std::string FragmentShaderRGBATexOpaque::getShaderString() const
 {
     return SHADER(
         precision mediump float;
         varying vec2 v_texCoord;
         uniform sampler2D s_texture;
-        uniform vec4 fragmentTexTransform;
         void main()
         {
-            vec2 texCoord = clamp(v_texCoord, 0.0, 1.0) * fragmentTexTransform.zw + fragmentTexTransform.xy;
-            vec4 texColor = texture2D(s_texture, texCoord);
+            vec4 texColor = texture2D(s_texture, v_texCoord);
             gl_FragColor = vec4(texColor.rgb, 1.0);
         }
     );
@@ -559,34 +493,30 @@ std::string FragmentShaderRGBATex::getShaderString() const
     );
 }
 
-std::string FragmentShaderRGBATexClampSwizzleAlpha::getShaderString() const
+std::string FragmentShaderRGBATexSwizzleAlpha::getShaderString() const
 {
     return SHADER(
         precision mediump float;
         varying vec2 v_texCoord;
         uniform sampler2D s_texture;
         uniform float alpha;
-        uniform vec4 fragmentTexTransform;
         void main()
         {
-            vec2 texCoord = clamp(v_texCoord, 0.0, 1.0) * fragmentTexTransform.zw + fragmentTexTransform.xy;
-            vec4 texColor = texture2D(s_texture, texCoord);
+            vec4 texColor = texture2D(s_texture, v_texCoord);
             gl_FragColor = vec4(texColor.z, texColor.y, texColor.x, texColor.w) * alpha;
         }
     );
 }
 
-std::string FragmentShaderRGBATexClampSwizzleOpaque::getShaderString() const
+std::string FragmentShaderRGBATexSwizzleOpaque::getShaderString() const
 {
     return SHADER(
         precision mediump float;
         varying vec2 v_texCoord;
         uniform sampler2D s_texture;
-        uniform vec4 fragmentTexTransform;
         void main()
         {
-            vec2 texCoord = clamp(v_texCoord, 0.0, 1.0) * fragmentTexTransform.zw + fragmentTexTransform.xy;
-            vec4 texColor = texture2D(s_texture, texCoord);
+            vec4 texColor = texture2D(s_texture, v_texCoord);
             gl_FragColor = vec4(texColor.z, texColor.y, texColor.x, 1.0);
         }
     );

cc/shader.h

@@ -142,22 +142,6 @@ private:
     int m_alphaLocation;
 };
 
-class FragmentTexClampAlphaBinding {
-public:
-    FragmentTexClampAlphaBinding();
-
-    void init(WebKit::WebGraphicsContext3D*, unsigned program, bool usingBindUniform, int* baseUniformIndex);
-    int alphaLocation() const { return m_alphaLocation; }
-    int edgeLocation() const { return -1; }
-    int fragmentTexTransformLocation() const { return m_fragmentTexTransformLocation; }
-    int samplerLocation() const { return m_samplerLocation; }
-
-private:
-    int m_samplerLocation;
-    int m_alphaLocation;
-    int m_fragmentTexTransformLocation;
-};
-
 class FragmentTexOpaqueBinding {
 public:
     FragmentTexOpaqueBinding();
@@ -172,21 +156,6 @@ private:
     int m_samplerLocation;
 };
 
-class FragmentTexClampOpaqueBinding {
-public:
-    FragmentTexClampOpaqueBinding();
-
-    void init(WebKit::WebGraphicsContext3D*, unsigned program, bool usingBindUniform, int* baseUniformIndex);
-    int alphaLocation() const { return -1; }
-    int edgeLocation() const { return -1; }
-    int fragmentTexTransformLocation() const { return m_fragmentTexTransformLocation; }
-    int samplerLocation() const { return m_samplerLocation; }
-
-private:
-    int m_samplerLocation;
-    int m_fragmentTexTransformLocation;
-};
-
 class FragmentShaderRGBATexFlipVaryingAlpha : public FragmentTexOpaqueBinding {
 public:
     std::string getShaderString() const;
@@ -202,11 +171,6 @@ public:
     std::string getShaderString() const;
 };
 
-class FragmentShaderRGBATexClampAlpha : public FragmentTexClampAlphaBinding {
-public:
-    std::string getShaderString() const;
-};
-
 class FragmentShaderRGBATexRectFlipVaryingAlpha : public FragmentTexAlphaBinding {
 public:
     std::string getShaderString() const;
@@ -217,7 +181,7 @@ public:
     std::string getShaderString() const;
 };
 
-class FragmentShaderRGBATexClampOpaque : public FragmentTexClampOpaqueBinding {
+class FragmentShaderRGBATexOpaque : public FragmentTexOpaqueBinding {
 public:
     std::string getShaderString() const;
 };
@@ -228,13 +192,13 @@ public:
 };
 
 // Swizzles the red and blue component of sampled texel with alpha.
-class FragmentShaderRGBATexClampSwizzleAlpha : public FragmentTexClampAlphaBinding {
+class FragmentShaderRGBATexSwizzleAlpha : public FragmentTexAlphaBinding {
 public:
     std::string getShaderString() const;
 };
 
 // Swizzles the red and blue component of sampled texel without alpha.
-class FragmentShaderRGBATexClampSwizzleOpaque : public FragmentTexClampOpaqueBinding {
+class FragmentShaderRGBATexSwizzleOpaque : public FragmentTexOpaqueBinding {
 public:
     std::string getShaderString() const;
 };