text: /*
   * 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 "GrShaderCaps.h"
  
  #include "GrContextOptions.h"
  #include "SkJSONWriter.h"
  
  ////////////////////////////////////////////////////////////////////////////////////////////
  
  GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
      fGLSLGeneration = k330_GrGLSLGeneration;
      fShaderDerivativeSupport = false;
      fGeometryShaderSupport = false;
      fGSInvocationsSupport = false;
      fPathRenderingSupport = false;
      fDstReadInShaderSupport = false;
      fDualSourceBlendingSupport = false;
      fIntegerSupport = false;
      fImageLoadStoreSupport = false;
      fDropsTileOnZeroDivide = false;
      fFBFetchSupport = false;
      fFBFetchNeedsCustomOutput = false;
      fUsesPrecisionModifiers = false;
      fCanUseAnyFunctionInShader = true;
      fCanUseMinAndAbsTogether = true;
      fCanUseFractForNegativeValues = true;
      fMustForceNegatedAtanParamToFloat = false;
      fAtan2ImplementedAsAtanYOverX = false;
      fMustDoOpBetweenFloorAndAbs = false;
      fRequiresLocalOutputColorForFBFetch = false;
      fMustObfuscateUniformColor = false;
      fMustGuardDivisionEvenAfterExplicitZeroCheck = false;
      fCanUseFragCoord = true;
      fIncompleteShortIntPrecision = false;
      fFlatInterpolationSupport = false;
      fPreferFlatInterpolation = false;
      fNoPerspectiveInterpolationSupport = false;
      fExternalTextureSupport = false;
      fVertexIDSupport = false;
      fFPManipulationSupport = false;
      fFloatIs32Bits = true;
      fHalfIs32Bits = false;
  
      fVersionDeclString = nullptr;
      fShaderDerivativeExtensionString = nullptr;
      fGeometryShaderExtensionString = nullptr;
      fGSInvocationsExtensionString = nullptr;
      fFragCoordConventionsExtensionString = nullptr;
      fSecondaryOutputExtensionString = nullptr;
      fExternalTextureExtensionString = nullptr;
      fSecondExternalTextureExtensionString = nullptr;
      fNoPerspectiveInterpolationExtensionString = nullptr;
      fFBFetchColorName = nullptr;
      fFBFetchExtensionString = nullptr;
      fImageLoadStoreExtensionString = nullptr;
      fMaxVertexSamplers = 0;
      fMaxGeometrySamplers = 0;
      fMaxFragmentSamplers = 0;
      fMaxCombinedSamplers = 0;
      fAdvBlendEqInteraction = kNotSupported_AdvBlendEqInteraction;
  }
  
  void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
      writer->beginObject();
  
      writer->appendBool("Shader Derivative Support", fShaderDerivativeSupport);
      writer->appendBool("Geometry Shader Support", fGeometryShaderSupport);
      writer->appendBool("Geometry Shader Invocations Support", fGSInvocationsSupport);
      writer->appendBool("Path Rendering Support", fPathRenderingSupport);
      writer->appendBool("Dst Read In Shader Support", fDstReadInShaderSupport);
      writer->appendBool("Dual Source Blending Support", fDualSourceBlendingSupport);
      writer->appendBool("Integer Support", fIntegerSupport);
      writer->appendBool("Image Load Store Support", fImageLoadStoreSupport);
  
      static const char* kAdvBlendEqInteractionStr[] = {
          "Not Supported",
          "Automatic",
          "General Enable",
          "Specific Enables",
      };
      GR_STATIC_ASSERT(0 == kNotSupported_AdvBlendEqInteraction);
      GR_STATIC_ASSERT(1 == kAutomatic_AdvBlendEqInteraction);
      GR_STATIC_ASSERT(2 == kGeneralEnable_AdvBlendEqInteraction);
      GR_STATIC_ASSERT(3 == kSpecificEnables_AdvBlendEqInteraction);
      GR_STATIC_ASSERT(SK_ARRAY_COUNT(kAdvBlendEqInteractionStr) == kLast_AdvBlendEqInteraction + 1);
  
      writer->appendBool("FB Fetch Support", fFBFetchSupport);
      writer->appendBool("Drops tile on zero divide", fDropsTileOnZeroDivide);
      writer->appendBool("Uses precision modifiers", fUsesPrecisionModifiers);
      writer->appendBool("Can use any() function", fCanUseAnyFunctionInShader);
      writer->appendBool("Can use min() and abs() together", fCanUseMinAndAbsTogether);
      writer->appendBool("Can use fract() for negative values", fCanUseFractForNegativeValues);
      writer->appendBool("Must force negated atan param to float", fMustForceNegatedAtanParamToFloat);
      writer->appendBool("Must do op between floor and abs", fMustDoOpBetweenFloorAndAbs);
      writer->appendBool("Must use local out color for FBFetch", fRequiresLocalOutputColorForFBFetch);
      writer->appendBool("Must obfuscate uniform color", fMustObfuscateUniformColor);
      writer->appendBool("Must guard division even after explicit zero check",
                         fMustGuardDivisionEvenAfterExplicitZeroCheck);
      writer->appendBool("Can use gl_FragCoord", fCanUseFragCoord);
      writer->appendBool("Incomplete short int precision", fIncompleteShortIntPrecision);
      writer->appendBool("Flat interpolation support", fFlatInterpolationSupport);
      writer->appendBool("Prefer flat interpolation", fPreferFlatInterpolation);
      writer->appendBool("No perspective interpolation support", fNoPerspectiveInterpolationSupport);
      writer->appendBool("External texture support", fExternalTextureSupport);
      writer->appendBool("sk_VertexID support", fVertexIDSupport);
      writer->appendBool("Floating point manipulation support", fFPManipulationSupport);
      writer->appendBool("float == fp32", fFloatIs32Bits);
      writer->appendBool("half == fp32", fHalfIs32Bits);
  
      writer->appendS32("Max VS Samplers", fMaxVertexSamplers);
      writer->appendS32("Max GS Samplers", fMaxGeometrySamplers);
      writer->appendS32("Max FS Samplers", fMaxFragmentSamplers);
      writer->appendS32("Max Combined Samplers", fMaxFragmentSamplers);
      writer->appendString("Advanced blend equation interaction",
                           kAdvBlendEqInteractionStr[fAdvBlendEqInteraction]);
  
      writer->endObject();
  }
  
  void GrShaderCaps::applyOptionsOverrides(const GrContextOptions& options) {
      if (options.fDisableDriverCorrectnessWorkarounds) {
          SkASSERT(fCanUseAnyFunctionInShader);
          SkASSERT(fCanUseMinAndAbsTogether);
          SkASSERT(fCanUseFractForNegativeValues);
          SkASSERT(!fMustForceNegatedAtanParamToFloat);
          SkASSERT(!fAtan2ImplementedAsAtanYOverX);
          SkASSERT(!fMustDoOpBetweenFloorAndAbs);
          SkASSERT(!fRequiresLocalOutputColorForFBFetch);
          SkASSERT(!fMustObfuscateUniformColor);
          SkASSERT(!fMustGuardDivisionEvenAfterExplicitZeroCheck);
          SkASSERT(fCanUseFragCoord);
          SkASSERT(!fIncompleteShortIntPrecision);
      }
  #if GR_TEST_UTILS
      fDualSourceBlendingSupport = fDualSourceBlendingSupport && !options.fSuppressDualSourceBlending;
  #endif
  }
  