Implement texel buffers

src/gpu/glsl/GrGLSLFragmentProcessor.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 "GrGLSLFragmentProcessor.h"
 #include "GrFragmentProcessor.h"
 #include "GrProcessor.h"
@@ skipping 57 matching lines @@
      * So if we're inside proc A's emitCode, and A is about to call emitCode on proc D, we want the
      * EmitArgs that's passed onto D to only contain its and its descendants' coords. The
      * EmitArgs given to A would contain the transforms [a1,b1,b2,c1,d1,e1,e2,e3,f1,f2], and we want
      * to extract the subset [d1,e1,e2,e3,f1,f2] to pass on to D. We can do this with a linear
      * search since we know that A has 1 transform (using A.numTransformsExclChildren()), and B's
      * subtree has 3 transforms (using B.numTransforms()), so we know the start of D's transforms is
      * 4 after the start of A's transforms.
      * Textures work the same way as transforms.
      */
     int firstCoordAt = args.fFp.numTransformsExclChildren();
-    int firstSamplerAt = args.fFp.numTexturesExclChildren();
+    int firstTextureAt = args.fFp.numTexturesExclChildren();
+    int firstBufferAt = args.fFp.numBuffersExclChildren();
     for (int i = 0; i < childIndex; ++i) {
         firstCoordAt += args.fFp.childProcessor(i).numTransforms();
-        firstSamplerAt += args.fFp.childProcessor(i).numTextures();
+        firstTextureAt += args.fFp.childProcessor(i).numTextures();
+        firstBufferAt += args.fFp.childProcessor(i).numBuffers();
     }
     GrGLSLTransformedCoordsArray childCoords;
     SamplerArray childTexSamplers;
+    SamplerArray childBufferSamplers;
     if (childProc.numTransforms() > 0) {
         childCoords.push_back_n(childProc.numTransforms(), &args.fCoords[firstCoordAt]);
     }
     if (childProc.numTextures() > 0) {
-        childTexSamplers.push_back_n(childProc.numTextures(), &args.fTexSamplers[firstSamplerAt]);
+        childTexSamplers.push_back_n(childProc.numTextures(), &args.fTexSamplers[firstTextureAt]);
+    }
+    if (childProc.numBuffers() > 0) {
+        childBufferSamplers.push_back_n(childProc.numBuffers(),
+                                        &args.fBufferSamplers[firstBufferAt]);
     }
 
     // emit the code for the child in its own scope
     fragBuilder->codeAppend("{\n");
     fragBuilder->codeAppendf("// Child Index %d (mangle: %s): %s\n", childIndex,
                              fragBuilder->getMangleString().c_str(), childProc.name());
     EmitArgs childArgs(fragBuilder,
                        args.fUniformHandler,
                        args.fGLSLCaps,
                        childProc,
                        outputColor,
                        inputColor,
                        childCoords,
-                       childTexSamplers);
+                       childTexSamplers,
+                       childBufferSamplers);
     this->childProcessor(childIndex)->emitCode(childArgs);
     fragBuilder->codeAppend("}\n");
 
     fragBuilder->onAfterChildProcEmitCode();
 }