Compute gl_FrontFacing using a single float constant.

src/compiler/OutputHLSL.cpp

@@ -213,8 +213,7 @@ void OutputHLSL::header()
 
         if (mUsesFrontFacing)
         {
-            out << "uniform bool dx_PointsOrLines;\n"
-                   "uniform bool dx_FrontCCW;\n";
+            out << "uniform float dx_FrontCCW;\n";
         }
         
         out << "\n";

src/libGLESv2/Context.cpp

@@ -1734,12 +1734,8 @@ void Context::applyState(GLenum drawMode)
     Framebuffer *framebufferObject = getDrawFramebuffer();
 
     GLint frontCCW = programBinary->getDxFrontCCWLocation();
-    GLint ccw = (mState.rasterizer.frontFace == GL_CCW);
-    programBinary->setUniform1iv(frontCCW, 1, &ccw);
-
-    GLint pointsOrLines = programBinary->getDxPointsOrLinesLocation();
-    GLint alwaysFront = !isTriangleMode(drawMode);
-    programBinary->setUniform1iv(pointsOrLines, 1, &alwaysFront);
+    GLfloat ccw = !isTriangleMode(drawMode) ? 0.0f : (mState.rasterizer.frontFace == GL_CCW ? 1.0f : -1.0f);
+    programBinary->setUniform1fv(frontCCW, 1, &ccw);
 
     mRenderer->setRasterizerState(mState.rasterizer);
 

src/libGLESv2/Context.h

@@ -69,8 +69,8 @@ enum
     MAX_TEXTURE_IMAGE_UNITS = 16,
     MAX_VERTEX_TEXTURE_IMAGE_UNITS_VTF = 4,   // For devices supporting vertex texture fetch
     MAX_COMBINED_TEXTURE_IMAGE_UNITS_VTF = MAX_TEXTURE_IMAGE_UNITS + MAX_VERTEX_TEXTURE_IMAGE_UNITS_VTF,    
-    MAX_FRAGMENT_UNIFORM_VECTORS_SM2 = 32 - 3,    // Reserve space for dx_Coord, dx_Depth, and dx_DepthRange. dx_PointOrLines and dx_FrontCCW use separate bool registers.
-    MAX_FRAGMENT_UNIFORM_VECTORS_SM3 = 224 - 3,
+    MAX_FRAGMENT_UNIFORM_VECTORS_SM2 = 32 - 4,    // Reserve space for dx_Coord, dx_Depth, dx_DepthRange and dx_FrontCCW.
+    MAX_FRAGMENT_UNIFORM_VECTORS_SM3 = 224 - 4,
     MAX_DRAW_BUFFERS = 1
 };
 

src/libGLESv2/ProgramBinary.cpp

@@ -87,7 +87,6 @@ ProgramBinary::ProgramBinary(rx::Renderer *renderer) : mRenderer(renderer), RefC
     mDxCoordLocation = -1;
     mDxHalfPixelSizeLocation = -1;
     mDxFrontCCWLocation = -1;
-    mDxPointsOrLinesLocation = -1;
 }
 
 ProgramBinary::~ProgramBinary()
@@ -1475,7 +1474,7 @@ bool ProgramBinary::linkVaryings(InfoLog &infoLog, std::string& pixelHLSL, std::
 
     if (fragmentShader->mUsesFrontFacing)
     {
-        pixelHLSL += "    gl_FrontFacing = dx_PointsOrLines || (dx_FrontCCW ? (input.vFace >= 0.0) : (input.vFace <= 0.0));\n";
+        pixelHLSL += "    gl_FrontFacing = (input.vFace * dx_FrontCCW >= 0.0);\n";
     }
 
     for (VaryingList::iterator varying = fragmentShader->mVaryings.begin(); varying != fragmentShader->mVaryings.end(); varying++)
@@ -1630,7 +1629,6 @@ bool ProgramBinary::load(InfoLog &infoLog, const void *binary, GLsizei length)
     stream.read(&mDxCoordLocation);
     stream.read(&mDxHalfPixelSizeLocation);
     stream.read(&mDxFrontCCWLocation);
-    stream.read(&mDxPointsOrLinesLocation);
 
     unsigned int pixelShaderSize;
     stream.read(&pixelShaderSize);
@@ -1739,7 +1737,6 @@ bool ProgramBinary::save(void* binary, GLsizei bufSize, GLsizei *length)
     stream.write(mDxCoordLocation);
     stream.write(mDxHalfPixelSizeLocation);
     stream.write(mDxFrontCCWLocation);
-    stream.write(mDxPointsOrLinesLocation);
 
     UINT pixelShaderSize = mPixelExecutable->getLength();
     stream.write(pixelShaderSize);
@@ -1866,7 +1863,6 @@ bool ProgramBinary::link(InfoLog &infoLog, const AttributeBindings &attributeBin
     mDxCoordLocation = getUniformLocation("dx_Coord");
     mDxHalfPixelSizeLocation = getUniformLocation("dx_HalfPixelSize");
     mDxFrontCCWLocation = getUniformLocation("dx_FrontCCW");
-    mDxPointsOrLinesLocation = getUniformLocation("dx_PointsOrLines");
 
     Context *context = getContext();
     context->markDxUniformsDirty();
@@ -2679,11 +2675,6 @@ GLint ProgramBinary::getDxFrontCCWLocation() const
     return mDxFrontCCWLocation;
 }
 
-GLint ProgramBinary::getDxPointsOrLinesLocation() const
-{
-    return mDxPointsOrLinesLocation;
-}
-
 ProgramBinary::Sampler::Sampler() : active(false), logicalTextureUnit(0), textureType(TEXTURE_2D)
 {
 }

src/libGLESv2/ProgramBinary.h

@@ -134,7 +134,6 @@ class ProgramBinary : public RefCountObject
     GLint getDxCoordLocation() const;
     GLint getDxHalfPixelSizeLocation() const;
     GLint getDxFrontCCWLocation() const;
-    GLint getDxPointsOrLinesLocation() const;
 
     void dirtyAllUniforms();
     void applyUniforms();
@@ -217,7 +216,6 @@ class ProgramBinary : public RefCountObject
     GLint mDxCoordLocation;
     GLint mDxHalfPixelSizeLocation;
     GLint mDxFrontCCWLocation;
-    GLint mDxPointsOrLinesLocation;
 
     bool mValidated;