Implement textureProjGrad and textureProjGradOffset.

src/compiler/translator/Initialize.cpp

@@ -525,6 +525,16 @@ void InsertBuiltInFunctions(ShShaderType type, ShShaderSpec spec, const ShBuiltI
     symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureGradOffset", gsampler2DArray, float3, float2, float2, int2);
     symbolTable.insertBuiltIn(ESSL3_BUILTINS, float1, "textureGradOffset", sampler2DArrayShadow, float4, float2, float2, int2);
 
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGrad", gsampler2D, float3, float2, float2);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGrad", gsampler2D, float4, float2, float2);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGrad", gsampler3D, float4, float3, float3);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, float1, "textureProjGrad", sampler2DShadow, float4, float2, float2);
+
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGradOffset", gsampler2D, float3, float2, float2, int2);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGradOffset", gsampler2D, float4, float2, float2, int2);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, gvec4, "textureProjGradOffset", gsampler3D, float4, float3, float3, int3);
+    symbolTable.insertBuiltIn(ESSL3_BUILTINS, float1, "textureProjGradOffset", sampler2DShadow, float4, float2, float2, int2);
+
     //
     // Depth range in window coordinates
     //

src/compiler/translator/OutputHLSL.cpp

@@ -2490,6 +2490,17 @@ bool OutputHLSL::visitAggregate(Visit visit, TIntermAggregate *node)
                     textureFunction.method = TextureFunction::GRAD;
                     textureFunction.offset = true;
                 }
+                else if (name == "textureProjGrad")
+                {
+                    textureFunction.method = TextureFunction::GRAD;
+                    textureFunction.proj = true;
+                }
+                else if (name == "textureProjGradOffset")
+                {
+                    textureFunction.method = TextureFunction::GRAD;
+                    textureFunction.proj = true;
+                    textureFunction.offset = true;
+                }
                 else UNREACHABLE();
 
                 if (textureFunction.method == TextureFunction::IMPLICIT)   // Could require lod 0 or have a bias argument