Fix various issues with framebuffer fetch

src/gpu/glsl/GrGLSLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLSLCaps.h"
 
 #include "GrContextOptions.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////
 
 GrGLSLCaps::GrGLSLCaps(const GrContextOptions& options) {
     fGLSLGeneration = k330_GrGLSLGeneration;
 
     fDropsTileOnZeroDivide = false;
     fFBFetchSupport = false;
     fFBFetchNeedsCustomOutput = false;
     fBindlessTextureSupport = false;
     fUsesPrecisionModifiers = false;
     fCanUseAnyFunctionInShader = true;
     fCanUseMinAndAbsTogether = true;
     fMustForceNegatedAtanParamToFloat = false;
+    fRequiresLocalOutputColorForFBFetch = false;
     fFlatInterpolationSupport = false;
     fNoPerspectiveInterpolationSupport = false;
     fMultisampleInterpolationSupport = false;
     fSampleVariablesSupport = false;
     fSampleMaskOverrideCoverageSupport = false;
     fExternalTextureSupport = false;
     fTexelFetchSupport = false;
     fVersionDeclString = nullptr;
     fShaderDerivativeExtensionString = nullptr;
     fFragCoordConventionsExtensionString = nullptr;
@@ skipping 30 matching lines @@
     r.appendf("--- GLSL-Specific ---\n");
 
     r.appendf("FB Fetch Support: %s\n", (fFBFetchSupport ? "YES" : "NO"));
     r.appendf("Drops tile on zero divide: %s\n", (fDropsTileOnZeroDivide ? "YES" : "NO"));
     r.appendf("Bindless texture support: %s\n", (fBindlessTextureSupport ? "YES" : "NO"));
     r.appendf("Uses precision modifiers: %s\n", (fUsesPrecisionModifiers ? "YES" : "NO"));
     r.appendf("Can use any() function: %s\n", (fCanUseAnyFunctionInShader ? "YES" : "NO"));
     r.appendf("Can use min() and abs() together: %s\n", (fCanUseMinAndAbsTogether ? "YES" : "NO"));
     r.appendf("Must force negated atan param to float: %s\n", (fMustForceNegatedAtanParamToFloat ?
                                                                "YES" : "NO"));
+    r.appendf("Must use local out color for FBFetch: %s\n", (fRequiresLocalOutputColorForFBFetch ?
+                                                             "YES" : "NO"));
     r.appendf("Flat interpolation support: %s\n", (fFlatInterpolationSupport ?  "YES" : "NO"));
     r.appendf("No perspective interpolation support: %s\n", (fNoPerspectiveInterpolationSupport ?
                                                              "YES" : "NO"));
     r.appendf("Multisample interpolation support: %s\n", (fMultisampleInterpolationSupport ?
                                                           "YES" : "NO"));
     r.appendf("Sample variables support: %s\n", (fSampleVariablesSupport ? "YES" : "NO"));
     r.appendf("Sample mask override coverage support: %s\n", (fSampleMaskOverrideCoverageSupport ?
                                                               "YES" : "NO"));
     r.appendf("External texture support: %s\n", (fExternalTextureSupport ? "YES" : "NO"));
     r.appendf("texelFetch support: %s\n", (fTexelFetchSupport ? "YES" : "NO"));
@@ skipping 56 matching lines @@
         table[kRGBA_float_GrPixelConfig] = kHigh_GrSLPrecision;
         table[kAlpha_half_GrPixelConfig] = mediump;
         table[kRGBA_half_GrPixelConfig]  = mediump;
 
         GR_STATIC_ASSERT(16 == kGrPixelConfigCnt);
     }
 }
 
 void GrGLSLCaps::onApplyOptionsOverrides(const GrContextOptions& options) {
 }