Reland Fixed FL9_3 shaders that use glPointCoord without glPointSize.

src/libANGLE/renderer/d3d/DynamicHLSL.cpp

@@ -797,6 +797,7 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data,
     const ShaderD3D *vertexShader      = GetImplAs<ShaderD3D>(vertexShaderGL);
     const gl::Shader *fragmentShaderGL = programData.getAttachedFragmentShader();
     const ShaderD3D *fragmentShader    = GetImplAs<ShaderD3D>(fragmentShaderGL);
+    const int shaderModel              = mRenderer->getMajorShaderModel();
 
     bool usesMRT        = fragmentShader->usesMultipleRenderTargets();
     bool usesFragCoord  = fragmentShader->usesFragCoord();
@@ -804,12 +805,14 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data,
     bool usesPointSize = vertexShader->usesPointSize();
     bool useInstancedPointSpriteEmulation =
         usesPointSize && mRenderer->getWorkarounds().useInstancedPointSpriteEmulation;
+    bool insertDummyPointCoordValue = !usesPointSize && usesPointCoord && shaderModel >= 4;
+    bool addPointCoord =
+        (useInstancedPointSpriteEmulation && usesPointCoord) || insertDummyPointCoordValue;
 
     // Validation done in the compiler
     ASSERT(!fragmentShader->usesFragColor() || !fragmentShader->usesFragData());
 
     // Write the HLSL input/output declarations
-    const int shaderModel     = mRenderer->getMajorShaderModel();
     const int registersNeeded = registers + (usesFragCoord ? 1 : 0) + (usesPointCoord ? 1 : 0);
 
     // Two cases when writing to gl_FragColor and using ESSL 1.0:
@@ -841,8 +844,7 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data,
     // gl_PointSize to be in VS_OUTPUT and GS_INPUT. Instanced point sprites doesn't need
     // gl_PointSize in VS_OUTPUT.
     const SemanticInfo &vertexSemantics =
-        getSemanticInfo(registers, outputPositionFromVS, usesFragCoord,
-                        (useInstancedPointSpriteEmulation && usesPointCoord),
+        getSemanticInfo(registers, outputPositionFromVS, usesFragCoord, addPointCoord,
                         (!useInstancedPointSpriteEmulation && usesPointSize), false);
 
     storeUserLinkedVaryings(packedVaryings, usesPointSize, linkedVaryings);
@@ -968,6 +970,16 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data,
         }
     }
 
+    // Renderers that enable instanced pointsprite emulation require the vertex shader output member
+    // gl_PointCoord to be set to a default value if used without gl_PointSize. 0.5,0.5 is the same
+    // default value used in the generated pixel shader.
+    if (insertDummyPointCoordValue)
+    {
+        ASSERT(!useInstancedPointSpriteEmulation);
+        vertexStream << "\n"
+                     << "    output.gl_PointCoord = float2(0.5, 0.5);\n";
+    }
+
     vertexStream << "\n"
                  << "    return output;\n"
                  << "}\n";