Changed auto child advance back to backwards linear search for getting subset of coords and sampler…

src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp

Index: src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp
diff --git a/src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp b/src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp
index 20bb3a389341a5bf1f614587d042a8ca3e0d91cf..a82b6b7f44dd2dfb734c8db78e6bcca0798a8be6 100644
--- a/src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp
+++ b/src/gpu/gl/builders/GrGLFragmentShaderBuilder.cpp
@@ -312,3 +312,52 @@ void GrGLFragmentBuilder::onAfterChildProcEmitCode() {
     int removeAt = fMangleString.findLastOf('_');
     fMangleString.remove(removeAt, fMangleString.size() - removeAt);
 }
+
+GrGLFragmentBuilder::AutoFragmentChildProcAdvance::AutoFragmentChildProcAdvance(
+                                                    int childProcIndex,
+                                                    GrGLFPBuilder* builder,
+                                                    const GrFragmentProcessor& fp,
+                                                    const char* outputColor,
+                                                    const TransformedCoordsArray& coords,
+                                                    const TextureSamplerArray& samplers,
+                                                    const GrFragmentProcessor** childFp,
+                                                    SkString* childOutputColor,
+                                                    TransformedCoordsArray* childCoords,
+                                                    TextureSamplerArray* childSamplers
+                                                    ) {
+        fFsb = builder->getFragmentShaderBuilder();
+        fFsb->onBeforeChildProcEmitCode();  // call first so mangleString is updated
+
+        const GrFragmentProcessor& childProc = fp.childProcessor(childProcIndex);
+        *childFp = &childProc;
+
+        // Mangle the name of the outputColor
+        childOutputColor->set(outputColor);
+        childOutputColor->append(fFsb->getMangleStringThisLevel());
+
+        // Find the subset of the transforms and textures that belongs to this child proc.
+        // Since we don't know how many transforms/textures at the head of the arrays
+        // belong to this proc and not one of its children, we have to do a backwards linear search
+        // from the ends of the arrays.
+        SkASSERT(childCoords->empty());
+        SkASSERT(childSamplers->empty());
+        int firstCoordAt = fp.numTransforms();
+        int firstSamplerAt = fp.numTextures();
+        for (int i = fp.numChildProcessors() - 1; i >= childProcIndex; --i) {
+            firstCoordAt -= fp.childProcessor(i).numTransforms();
+            firstSamplerAt -= fp.childProcessor(i).numTextures();
+        }
+        if (!coords.empty())
+            childCoords->push_back_n(childProc.numTransforms(), &coords[firstCoordAt]);
+        if (!samplers.empty())
+            childSamplers->push_back_n(childProc.numTextures(), &samplers[firstSamplerAt]);
+
+        fFsb->codeAppendf("vec4 %s;\n", childOutputColor->c_str());
+        fFsb->codeAppend("{\n");
+        fFsb->codeAppendf("// Child %d: %s\n", fFsb->getChildNumberThisLevel(), childProc.name());
+}
+
+GrGLFragmentBuilder::AutoFragmentChildProcAdvance::~AutoFragmentChildProcAdvance() {
+    fFsb->codeAppend("}\n");
+    fFsb->onAfterChildProcEmitCode();
+}