Mangle output var in GrGLFragmentProcessor::emitChild

src/gpu/effects/GrXfermodeFragmentProcessor.cpp

 /*
 * Copyright 2015 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #include "effects/GrXfermodeFragmentProcessor.h"
 
 #include "GrFragmentProcessor.h"
@@ skipping 88 matching lines @@
     const char* inputAlpha = nullptr;
     if (args.fInputColor) {
         inputAlpha = "inputAlpha";
         opaqueInput = "opaqueInput";
         fsBuilder->codeAppendf("float inputAlpha = %s.a;", args.fInputColor);
         fsBuilder->codeAppendf("vec4 opaqueInput = vec4(%s.rgb / inputAlpha, 1);",
                                args.fInputColor);
     }
 
     // declare outputColor and emit the code for each of the two children
-    SkString outputColorSrc(args.fOutputColor);
-    outputColorSrc.append("_src");
-    fsBuilder->codeAppendf("vec4 %s;\n", outputColorSrc.c_str());
-    this->emitChild(0, opaqueInput, outputColorSrc.c_str(), args);
+    SkString srcColor("src");
+    this->emitChild(0, opaqueInput, &srcColor, args);
 
-    SkString outputColorDst(args.fOutputColor);
-    outputColorDst.append("_dst");
-    fsBuilder->codeAppendf("vec4 %s;\n", outputColorDst.c_str());
-    this->emitChild(1, opaqueInput, outputColorDst.c_str(), args);
+    SkString dstColor("dst");
+    this->emitChild(1, opaqueInput, &dstColor, args);
 
     // emit blend code
     SkXfermode::Mode mode = cs.getMode();
-    fsBuilder->codeAppend("{");
     fsBuilder->codeAppendf("// Compose Xfer Mode: %s\n", SkXfermode::ModeName(mode));
-    GrGLSLBlend::AppendMode(fsBuilder, outputColorSrc.c_str(),
-                             outputColorDst.c_str(), args.fOutputColor, mode);
-    fsBuilder->codeAppend("}");
+    GrGLSLBlend::AppendMode(fsBuilder, srcColor.c_str(), dstColor.c_str(), args.fOutputColor, mode);
 
     // re-multiply the output color by the input color's alpha
     if (inputAlpha) {
         fsBuilder->codeAppendf("%s *= %s;", args.fOutputColor, inputAlpha);
     }
 }
 
 const GrFragmentProcessor* GrXfermodeFragmentProcessor::CreateFromTwoProcessors(
          const GrFragmentProcessor* src, const GrFragmentProcessor* dst, SkXfermode::Mode mode) {
     switch (mode) {
@@ skipping 94 matching lines @@
 
 class GLComposeOneFragmentProcessor : public GrGLFragmentProcessor {
 public:
     GLComposeOneFragmentProcessor(const GrProcessor& processor) {}
 
     void emitCode(EmitArgs& args) override {
         GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
         SkXfermode::Mode mode = args.fFp.cast<ComposeOneFragmentProcessor>().mode();
         ComposeOneFragmentProcessor::Child child =
             args.fFp.cast<ComposeOneFragmentProcessor>().child();
-        // declare _dstColor and emit the code for the two child
-        fsBuilder->codeAppendf("vec4 _child;");
-        this->emitChild(0, nullptr, "_child", args);
+        SkString childColor("child");
+        this->emitChild(0, nullptr, &childColor, args);
 
         const char* inputColor = args.fInputColor;
         // We don't try to optimize for this case at all
         if (!inputColor) {
             fsBuilder->codeAppendf("const vec4 ones = vec4(1);");
             inputColor = "ones";
         }
 
         // emit blend code
-        fsBuilder->codeAppend("{");
         fsBuilder->codeAppendf("// Compose Xfer Mode: %s\n", SkXfermode::ModeName(mode));
+        const char* childStr = childColor.c_str();
         if (ComposeOneFragmentProcessor::kDst_Child == child) {
-            GrGLSLBlend::AppendMode(fsBuilder, inputColor, "_child", args.fOutputColor, mode);
+            GrGLSLBlend::AppendMode(fsBuilder, inputColor, childStr, args.fOutputColor, mode);
         } else {
-            GrGLSLBlend::AppendMode(fsBuilder, "_child", inputColor, args.fOutputColor, mode);
+            GrGLSLBlend::AppendMode(fsBuilder, childStr, inputColor, args.fOutputColor, mode);
         }
-        fsBuilder->codeAppend("}");
     }
 
 private:
     typedef GrGLFragmentProcessor INHERITED;
 };
 
 /////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(ComposeOneFragmentProcessor);
 
@@ skipping 36 matching lines @@
         case SkXfermode::kClear_Mode:
             return GrConstColorProcessor::Create(GrColor_TRANSPARENT_BLACK,
                                                  GrConstColorProcessor::kIgnore_InputMode);
         case SkXfermode::kDst_Mode:
             return nullptr;
         default:
             return new ComposeOneFragmentProcessor(src, mode,
                                                    ComposeOneFragmentProcessor::kSrc_Child);
     }
 }