The Tor Browser: gfx/skia/trunk/src/effects/SkDisplacementMapEffect.cpp@6474c204b198 (annotated)

gfx/skia/trunk/src/effects/SkDisplacementMapEffect.cpp@6474c204b198 (annotated)

gfx/skia/trunk/src/effects/SkDisplacementMapEffect.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkDisplacementMapEffect.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkUnPreMultiply.h"
 #include "SkColorPriv.h"
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrCoordTransform.h"
 #include "gl/GrGLEffect.h"
 #include "GrTBackendEffectFactory.h"
 #endif
 namespace {
 #define kChannelSelectorKeyBits 3; // Max value is 4, so 3 bits are required at most
 template<SkDisplacementMapEffect::ChannelSelectorType type>
 uint32_t getValue(SkColor, const SkUnPreMultiply::Scale*) {
     SkDEBUGFAIL("Unknown channel selector");
     return 0;
 }
 template<> uint32_t getValue<SkDisplacementMapEffect::kR_ChannelSelectorType>(
     SkColor l, const SkUnPreMultiply::Scale* table) {
     return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedR32(l));
 }
 template<> uint32_t getValue<SkDisplacementMapEffect::kG_ChannelSelectorType>(
     SkColor l, const SkUnPreMultiply::Scale* table) {
     return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedG32(l));
 }
 template<> uint32_t getValue<SkDisplacementMapEffect::kB_ChannelSelectorType>(
     SkColor l, const SkUnPreMultiply::Scale* table) {
     return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedB32(l));
 }
 template<> uint32_t getValue<SkDisplacementMapEffect::kA_ChannelSelectorType>(
     SkColor l, const SkUnPreMultiply::Scale*) {
     return SkGetPackedA32(l);
 }
 template<SkDisplacementMapEffect::ChannelSelectorType typeX,
          SkDisplacementMapEffect::ChannelSelectorType typeY>
 void computeDisplacement(const SkVector& scale, SkBitmap* dst,
                          SkBitmap* displ, const SkIPoint& offset,
                          SkBitmap* src,
                          const SkIRect& bounds)
 {
     static const SkScalar Inv8bit = SkScalarDiv(SK_Scalar1, 255.0f);
     const int srcW = src->width();
     const int srcH = src->height();
     const SkVector scaleForColor = SkVector::Make(SkScalarMul(scale.fX, Inv8bit),
                                                   SkScalarMul(scale.fY, Inv8bit));
     const SkVector scaleAdj = SkVector::Make(SK_ScalarHalf - SkScalarMul(scale.fX, SK_ScalarHalf),
                                              SK_ScalarHalf - SkScalarMul(scale.fY, SK_ScalarHalf));
     const SkUnPreMultiply::Scale* table = SkUnPreMultiply::GetScaleTable();
     SkPMColor* dstPtr = dst->getAddr32(0, 0);
     for (int y = bounds.top(); y < bounds.bottom(); ++y) {
         const SkPMColor* displPtr = displ->getAddr32(bounds.left() + offset.fX,
                                                      y + offset.fY);
         for (int x = bounds.left(); x < bounds.right(); ++x, ++displPtr) {
             const SkScalar displX = SkScalarMul(scaleForColor.fX,
                 SkIntToScalar(getValue<typeX>(*displPtr, table))) + scaleAdj.fX;
             const SkScalar displY = SkScalarMul(scaleForColor.fY,
                 SkIntToScalar(getValue<typeY>(*displPtr, table))) + scaleAdj.fY;
             // Truncate the displacement values
             const int srcX = x + SkScalarTruncToInt(displX);
             const int srcY = y + SkScalarTruncToInt(displY);
             *dstPtr++ = ((srcX < 0) || (srcX >= srcW) || (srcY < 0) || (srcY >= srcH)) ?
 : *(src->getAddr32(srcX, srcY));
         }
     }
 }
 template<SkDisplacementMapEffect::ChannelSelectorType typeX>
 void computeDisplacement(SkDisplacementMapEffect::ChannelSelectorType yChannelSelector,
                          const SkVector& scale, SkBitmap* dst,
                          SkBitmap* displ, const SkIPoint& offset,
                          SkBitmap* src,
                          const SkIRect& bounds)
 {
     switch (yChannelSelector) {
       case SkDisplacementMapEffect::kR_ChannelSelectorType:
         computeDisplacement<typeX, SkDisplacementMapEffect::kR_ChannelSelectorType>(
             scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kG_ChannelSelectorType:
         computeDisplacement<typeX, SkDisplacementMapEffect::kG_ChannelSelectorType>(
             scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kB_ChannelSelectorType:
         computeDisplacement<typeX, SkDisplacementMapEffect::kB_ChannelSelectorType>(
             scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kA_ChannelSelectorType:
         computeDisplacement<typeX, SkDisplacementMapEffect::kA_ChannelSelectorType>(
             scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
       default:
         SkDEBUGFAIL("Unknown Y channel selector");
     }
 }
 void computeDisplacement(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector,
                          SkDisplacementMapEffect::ChannelSelectorType yChannelSelector,
                          const SkVector& scale, SkBitmap* dst,
                          SkBitmap* displ, const SkIPoint& offset,
                          SkBitmap* src,
                          const SkIRect& bounds)
 {
     switch (xChannelSelector) {
       case SkDisplacementMapEffect::kR_ChannelSelectorType:
         computeDisplacement<SkDisplacementMapEffect::kR_ChannelSelectorType>(
             yChannelSelector, scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kG_ChannelSelectorType:
         computeDisplacement<SkDisplacementMapEffect::kG_ChannelSelectorType>(
             yChannelSelector, scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kB_ChannelSelectorType:
         computeDisplacement<SkDisplacementMapEffect::kB_ChannelSelectorType>(
             yChannelSelector, scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kA_ChannelSelectorType:
         computeDisplacement<SkDisplacementMapEffect::kA_ChannelSelectorType>(
             yChannelSelector, scale, dst, displ, offset, src, bounds);
         break;
       case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
       default:
         SkDEBUGFAIL("Unknown X channel selector");
     }
 }
 bool channel_selector_type_is_valid(SkDisplacementMapEffect::ChannelSelectorType cst) {
     switch (cst) {
     case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
     case SkDisplacementMapEffect::kR_ChannelSelectorType:
     case SkDisplacementMapEffect::kG_ChannelSelectorType:
     case SkDisplacementMapEffect::kB_ChannelSelectorType:
     case SkDisplacementMapEffect::kA_ChannelSelectorType:
         return true;
     default:
         break;
     }
     return false;
 }
 } // end namespace
 ///////////////////////////////////////////////////////////////////////////////
 SkDisplacementMapEffect::SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
                                                  ChannelSelectorType yChannelSelector,
                                                  SkScalar scale,
                                                  SkImageFilter* displacement,
                                                  SkImageFilter* color,
                                                  const CropRect* cropRect)
   : INHERITED(displacement, color, cropRect)
   , fXChannelSelector(xChannelSelector)
   , fYChannelSelector(yChannelSelector)
   , fScale(scale)
 {
 }
 SkDisplacementMapEffect::~SkDisplacementMapEffect() {
 }
 SkDisplacementMapEffect::SkDisplacementMapEffect(SkReadBuffer& buffer)
   : INHERITED(2, buffer)
 {
     fXChannelSelector = (SkDisplacementMapEffect::ChannelSelectorType) buffer.readInt();
     fYChannelSelector = (SkDisplacementMapEffect::ChannelSelectorType) buffer.readInt();
     fScale            = buffer.readScalar();
     buffer.validate(channel_selector_type_is_valid(fXChannelSelector) &&
                     channel_selector_type_is_valid(fYChannelSelector) &&
                     SkScalarIsFinite(fScale));
 }
 void SkDisplacementMapEffect::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeInt((int) fXChannelSelector);
     buffer.writeInt((int) fYChannelSelector);
     buffer.writeScalar(fScale);
 }
 bool SkDisplacementMapEffect::onFilterImage(Proxy* proxy,
                                             const SkBitmap& src,
                                             const Context& ctx,
                                             SkBitmap* dst,
                                             SkIPoint* offset) const {
     SkBitmap displ = src, color = src;
     const SkImageFilter* colorInput = getColorInput();
     const SkImageFilter* displInput = getDisplacementInput();
     SkIPoint colorOffset = SkIPoint::Make(0, 0), displOffset = SkIPoint::Make(0, 0);
     if ((colorInput && !colorInput->filterImage(proxy, src, ctx, &color, &colorOffset)) ||
         (displInput && !displInput->filterImage(proxy, src, ctx, &displ, &displOffset))) {
         return false;
     }
     if ((displ.colorType() != kPMColor_SkColorType) ||
         (color.colorType() != kPMColor_SkColorType)) {
         return false;
     }
     SkIRect bounds;
     // Since computeDisplacement does bounds checking on color pixel access, we don't need to pad
     // the color bitmap to bounds here.
     if (!this->applyCropRect(ctx, color, colorOffset, &bounds)) {
         return false;
     }
     SkIRect displBounds;
     if (!this->applyCropRect(ctx, proxy, displ, &displOffset, &displBounds, &displ)) {
         return false;
     }
     if (!bounds.intersect(displBounds)) {
         return false;
     }
     SkAutoLockPixels alp_displacement(displ), alp_color(color);
     if (!displ.getPixels() || !color.getPixels()) {
         return false;
     }
     dst->setConfig(color.config(), bounds.width(), bounds.height());
     if (!dst->allocPixels()) {
         return false;
     }
     SkVector scale = SkVector::Make(fScale, fScale);
     ctx.ctm().mapVectors(&scale, 1);
     SkIRect colorBounds = bounds;
     colorBounds.offset(-colorOffset);
     computeDisplacement(fXChannelSelector, fYChannelSelector, scale, dst,
                         &displ, colorOffset - displOffset, &color, colorBounds);
     offset->fX = bounds.left();
     offset->fY = bounds.top();
     return true;
 }
 void SkDisplacementMapEffect::computeFastBounds(const SkRect& src, SkRect* dst) const {
     if (getColorInput()) {
         getColorInput()->computeFastBounds(src, dst);
     } else {
         *dst = src;
     }
     dst->outset(fScale * SK_ScalarHalf, fScale * SK_ScalarHalf);
 }
 bool SkDisplacementMapEffect::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
                                    SkIRect* dst) const {
     SkIRect bounds = src;
     if (getColorInput() && !getColorInput()->filterBounds(src, ctm, &bounds)) {
         return false;
     }
     bounds.outset(SkScalarCeilToInt(fScale * SK_ScalarHalf),
                   SkScalarCeilToInt(fScale * SK_ScalarHalf));
     *dst = bounds;
     return true;
 }
 ///////////////////////////////////////////////////////////////////////////////
 #if SK_SUPPORT_GPU
 class GrGLDisplacementMapEffect : public GrGLEffect {
 public:
     GrGLDisplacementMapEffect(const GrBackendEffectFactory& factory,
                               const GrDrawEffect& drawEffect);
     virtual ~GrGLDisplacementMapEffect();
     virtual void emitCode(GrGLShaderBuilder*,
                           const GrDrawEffect&,
                           EffectKey,
                           const char* outputColor,
                           const char* inputColor,
                           const TransformedCoordsArray&,
                           const TextureSamplerArray&) SK_OVERRIDE;
     static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
     virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
 private:
     SkDisplacementMapEffect::ChannelSelectorType fXChannelSelector;
     SkDisplacementMapEffect::ChannelSelectorType fYChannelSelector;
     GrGLUniformManager::UniformHandle fScaleUni;
     typedef GrGLEffect INHERITED;
 };
 ///////////////////////////////////////////////////////////////////////////////
 class GrDisplacementMapEffect : public GrEffect {
 public:
     static GrEffectRef* Create(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector,
                                SkDisplacementMapEffect::ChannelSelectorType yChannelSelector,
                                SkVector scale,
                                GrTexture* displacement, const SkMatrix& offsetMatrix,
                                GrTexture* color) {
         AutoEffectUnref effect(SkNEW_ARGS(GrDisplacementMapEffect, (xChannelSelector,
                                                                     yChannelSelector,
                                                                     scale,
                                                                     displacement,
                                                                     offsetMatrix,
                                                                     color)));
         return CreateEffectRef(effect);
     }
     virtual ~GrDisplacementMapEffect();
     virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
     SkDisplacementMapEffect::ChannelSelectorType xChannelSelector() const
         { return fXChannelSelector; }
     SkDisplacementMapEffect::ChannelSelectorType yChannelSelector() const
         { return fYChannelSelector; }
     const SkVector& scale() const { return fScale; }
     typedef GrGLDisplacementMapEffect GLEffect;
     static const char* Name() { return "DisplacementMap"; }
     virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE;
 private:
     virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE;
     GrDisplacementMapEffect(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector,
                             SkDisplacementMapEffect::ChannelSelectorType yChannelSelector,
                             const SkVector& scale,
                             GrTexture* displacement, const SkMatrix& offsetMatrix,
                             GrTexture* color);
     GR_DECLARE_EFFECT_TEST;
     GrCoordTransform            fDisplacementTransform;
     GrTextureAccess             fDisplacementAccess;
     GrCoordTransform            fColorTransform;
     GrTextureAccess             fColorAccess;
     SkDisplacementMapEffect::ChannelSelectorType fXChannelSelector;
     SkDisplacementMapEffect::ChannelSelectorType fYChannelSelector;
     SkVector fScale;
     typedef GrEffect INHERITED;
 };
 bool SkDisplacementMapEffect::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Context& ctx,
                                              SkBitmap* result, SkIPoint* offset) const {
     SkBitmap colorBM = src;
     SkIPoint colorOffset = SkIPoint::Make(0, 0);
     if (getColorInput() && !getColorInput()->getInputResultGPU(proxy, src, ctx, &colorBM,
                                                                &colorOffset)) {
         return false;
     }
     SkBitmap displacementBM = src;
     SkIPoint displacementOffset = SkIPoint::Make(0, 0);
     if (getDisplacementInput() &&
         !getDisplacementInput()->getInputResultGPU(proxy, src, ctx, &displacementBM,
                                                    &displacementOffset)) {
         return false;
     }
     SkIRect bounds;
     // Since GrDisplacementMapEffect does bounds checking on color pixel access, we don't need to
     // pad the color bitmap to bounds here.
     if (!this->applyCropRect(ctx, colorBM, colorOffset, &bounds)) {
         return false;
     }
     SkIRect displBounds;
     if (!this->applyCropRect(ctx, proxy, displacementBM,
                              &displacementOffset, &displBounds, &displacementBM)) {
         return false;
     }
     if (!bounds.intersect(displBounds)) {
         return false;
     }
     GrTexture* color = colorBM.getTexture();
     GrTexture* displacement = displacementBM.getTexture();
     GrContext* context = color->getContext();
     GrTextureDesc desc;
     desc.fFlags = kRenderTarget_GrTextureFlagBit | kNoStencil_GrTextureFlagBit;
     desc.fWidth = colorBM.width();
     desc.fHeight = colorBM.height();
     desc.fConfig = kSkia8888_GrPixelConfig;
     GrAutoScratchTexture ast(context, desc);
     SkAutoTUnref<GrTexture> dst(ast.detach());
     GrContext::AutoRenderTarget art(context, dst->asRenderTarget());
     SkVector scale = SkVector::Make(fScale, fScale);
     ctx.ctm().mapVectors(&scale, 1);
     GrPaint paint;
     SkMatrix offsetMatrix = GrEffect::MakeDivByTextureWHMatrix(displacement);
     offsetMatrix.preTranslate(SkIntToScalar(colorOffset.fX - displacementOffset.fX),
                               SkIntToScalar(colorOffset.fY - displacementOffset.fY));
     paint.addColorEffect(
         GrDisplacementMapEffect::Create(fXChannelSelector,
                                         fYChannelSelector,
                                         scale,
                                         displacement,
                                         offsetMatrix,
                                         color))->unref();
     SkIRect colorBounds = bounds;
     colorBounds.offset(-colorOffset);
     SkMatrix matrix;
     matrix.setTranslate(-SkIntToScalar(colorBounds.x()),
                         -SkIntToScalar(colorBounds.y()));
     context->concatMatrix(matrix);
     context->drawRect(paint, SkRect::Make(colorBounds));
     offset->fX = bounds.left();
     offset->fY = bounds.top();
     WrapTexture(dst, bounds.width(), bounds.height(), result);
     return true;
 }
 ///////////////////////////////////////////////////////////////////////////////
 GrDisplacementMapEffect::GrDisplacementMapEffect(
                              SkDisplacementMapEffect::ChannelSelectorType xChannelSelector,
                              SkDisplacementMapEffect::ChannelSelectorType yChannelSelector,
                              const SkVector& scale,
                              GrTexture* displacement,
                              const SkMatrix& offsetMatrix,
                              GrTexture* color)
     : fDisplacementTransform(kLocal_GrCoordSet, offsetMatrix, displacement)
     , fDisplacementAccess(displacement)
     , fColorTransform(kLocal_GrCoordSet, color)
     , fColorAccess(color)
     , fXChannelSelector(xChannelSelector)
     , fYChannelSelector(yChannelSelector)
     , fScale(scale) {
     this->addCoordTransform(&fDisplacementTransform);
     this->addTextureAccess(&fDisplacementAccess);
     this->addCoordTransform(&fColorTransform);
     this->addTextureAccess(&fColorAccess);
     this->setWillNotUseInputColor();
 }
 GrDisplacementMapEffect::~GrDisplacementMapEffect() {
 }
 bool GrDisplacementMapEffect::onIsEqual(const GrEffect& sBase) const {
     const GrDisplacementMapEffect& s = CastEffect<GrDisplacementMapEffect>(sBase);
     return fDisplacementAccess.getTexture() == s.fDisplacementAccess.getTexture() &&
            fColorAccess.getTexture() == s.fColorAccess.getTexture() &&
            fXChannelSelector == s.fXChannelSelector &&
            fYChannelSelector == s.fYChannelSelector &&
            fScale == s.fScale;
 }
 const GrBackendEffectFactory& GrDisplacementMapEffect::getFactory() const {
     return GrTBackendEffectFactory<GrDisplacementMapEffect>::getInstance();
 }
 void GrDisplacementMapEffect::getConstantColorComponents(GrColor*,
                                                          uint32_t* validFlags) const {
     // Any displacement offset bringing a pixel out of bounds will output a color of (0,0,0,0),
     // so the only way we'd get a constant alpha is if the input color image has a constant alpha
     // and no displacement offset push any texture coordinates out of bounds OR if the constant
     // alpha is 0. Since this isn't trivial to compute at this point, let's assume the output is
     // not of constant color when a displacement effect is applied.
     *validFlags = 0;
 }
 ///////////////////////////////////////////////////////////////////////////////
 GR_DEFINE_EFFECT_TEST(GrDisplacementMapEffect);
 GrEffectRef* GrDisplacementMapEffect::TestCreate(SkRandom* random,
                                                  GrContext*,
                                                  const GrDrawTargetCaps&,
                                                  GrTexture* textures[]) {
     int texIdxDispl = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
                                            GrEffectUnitTest::kAlphaTextureIdx;
     int texIdxColor = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
                                            GrEffectUnitTest::kAlphaTextureIdx;
     static const int kMaxComponent = 4;
     SkDisplacementMapEffect::ChannelSelectorType xChannelSelector =
         static_cast<SkDisplacementMapEffect::ChannelSelectorType>(
         random->nextRangeU(1, kMaxComponent));
     SkDisplacementMapEffect::ChannelSelectorType yChannelSelector =
         static_cast<SkDisplacementMapEffect::ChannelSelectorType>(
         random->nextRangeU(1, kMaxComponent));
     SkVector scale = SkVector::Make(random->nextRangeScalar(0, 100.0f),
                                     random->nextRangeScalar(0, 100.0f));
     return GrDisplacementMapEffect::Create(xChannelSelector, yChannelSelector, scale,
                                            textures[texIdxDispl], SkMatrix::I(),
                                            textures[texIdxColor]);
 }
 ///////////////////////////////////////////////////////////////////////////////
 GrGLDisplacementMapEffect::GrGLDisplacementMapEffect(const GrBackendEffectFactory& factory,
                                                      const GrDrawEffect& drawEffect)
     : INHERITED(factory)
     , fXChannelSelector(drawEffect.castEffect<GrDisplacementMapEffect>().xChannelSelector())
     , fYChannelSelector(drawEffect.castEffect<GrDisplacementMapEffect>().yChannelSelector()) {
 }
 GrGLDisplacementMapEffect::~GrGLDisplacementMapEffect() {
 }
 void GrGLDisplacementMapEffect::emitCode(GrGLShaderBuilder* builder,
                                          const GrDrawEffect&,
                                          EffectKey key,
                                          const char* outputColor,
                                          const char* inputColor,
                                          const TransformedCoordsArray& coords,
                                          const TextureSamplerArray& samplers) {
     sk_ignore_unused_variable(inputColor);
     fScaleUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                     kVec2f_GrSLType, "Scale");
     const char* scaleUni = builder->getUniformCStr(fScaleUni);
     const char* dColor = "dColor";
     const char* cCoords = "cCoords";
     const char* outOfBounds = "outOfBounds";
     const char* nearZero = "1e-6"; // Since 6.10352e−5 is the smallest half float, use
                                    // a number smaller than that to approximate 0, but
                                    // leave room for 32-bit float GPU rounding errors.
     builder->fsCodeAppendf("\t\tvec4 %s = ", dColor);
     builder->fsAppendTextureLookup(samplers[0], coords[0].c_str(), coords[0].type());
     builder->fsCodeAppend(";\n");
     // Unpremultiply the displacement
     builder->fsCodeAppendf("\t\t%s.rgb = (%s.a < %s) ? vec3(0.0) : clamp(%s.rgb / %s.a, 0.0, 1.0);",
                            dColor, dColor, nearZero, dColor, dColor);
     builder->fsCodeAppendf("\t\tvec2 %s = %s + %s*(%s.",
                            cCoords, coords[1].c_str(), scaleUni, dColor);
     switch (fXChannelSelector) {
       case SkDisplacementMapEffect::kR_ChannelSelectorType:
         builder->fsCodeAppend("r");
         break;
       case SkDisplacementMapEffect::kG_ChannelSelectorType:
         builder->fsCodeAppend("g");
         break;
       case SkDisplacementMapEffect::kB_ChannelSelectorType:
         builder->fsCodeAppend("b");
         break;
       case SkDisplacementMapEffect::kA_ChannelSelectorType:
         builder->fsCodeAppend("a");
         break;
       case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
       default:
         SkDEBUGFAIL("Unknown X channel selector");
     }
     switch (fYChannelSelector) {
       case SkDisplacementMapEffect::kR_ChannelSelectorType:
         builder->fsCodeAppend("r");
         break;
       case SkDisplacementMapEffect::kG_ChannelSelectorType:
         builder->fsCodeAppend("g");
         break;
       case SkDisplacementMapEffect::kB_ChannelSelectorType:
         builder->fsCodeAppend("b");
         break;
       case SkDisplacementMapEffect::kA_ChannelSelectorType:
         builder->fsCodeAppend("a");
         break;
       case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
       default:
         SkDEBUGFAIL("Unknown Y channel selector");
     }
     builder->fsCodeAppend("-vec2(0.5));\t\t");
     // FIXME : This can be achieved with a "clamp to border" texture repeat mode and
     //         a 0 border color instead of computing if cCoords is out of bounds here.
     builder->fsCodeAppendf(
         "bool %s = (%s.x < 0.0) || (%s.y < 0.0) || (%s.x > 1.0) || (%s.y > 1.0);\t\t",
         outOfBounds, cCoords, cCoords, cCoords, cCoords);
     builder->fsCodeAppendf("%s = %s ? vec4(0.0) : ", outputColor, outOfBounds);
     builder->fsAppendTextureLookup(samplers[1], cCoords, coords[1].type());
     builder->fsCodeAppend(";\n");
 }
 void GrGLDisplacementMapEffect::setData(const GrGLUniformManager& uman,
                                         const GrDrawEffect& drawEffect) {
     const GrDisplacementMapEffect& displacementMap =
         drawEffect.castEffect<GrDisplacementMapEffect>();
     GrTexture* colorTex = displacementMap.texture(1);
     SkScalar scaleX = SkScalarDiv(displacementMap.scale().fX, SkIntToScalar(colorTex->width()));
     SkScalar scaleY = SkScalarDiv(displacementMap.scale().fY, SkIntToScalar(colorTex->height()));
     uman.set2f(fScaleUni, SkScalarToFloat(scaleX),
                colorTex->origin() == kTopLeft_GrSurfaceOrigin ?
                SkScalarToFloat(scaleY) : SkScalarToFloat(-scaleY));
 }
 GrGLEffect::EffectKey GrGLDisplacementMapEffect::GenKey(const GrDrawEffect& drawEffect,
                                                         const GrGLCaps&) {
     const GrDisplacementMapEffect& displacementMap =
         drawEffect.castEffect<GrDisplacementMapEffect>();
     EffectKey xKey = displacementMap.xChannelSelector();
     EffectKey yKey = displacementMap.yChannelSelector() << kChannelSelectorKeyBits;
     return xKey | yKey;
 }
 #endif

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gfx/skia/trunk/src/effects/SkDisplacementMapEffect.cpp@6474c204b198 (annotated)

gfx/skia/trunk/src/effects/SkDisplacementMapEffect.cpp