| /* |
| * 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 "SkArenaAlloc.h" |
| #include "SkBitmapProcShader.h" |
| #include "SkBitmapProcState.h" |
| #include "SkColor.h" |
| #include "SkColorSpaceXformer.h" |
| #include "SkEmptyShader.h" |
| #include "SkLightingShader.h" |
| #include "SkMathPriv.h" |
| #include "SkNormalSource.h" |
| #include "SkPoint3.h" |
| #include "SkReadBuffer.h" |
| #include "SkShaderBase.h" |
| #include "SkWriteBuffer.h" |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /* |
| SkLightingShader TODOs: |
| support different light types |
| support multiple lights |
| fix non-opaque diffuse textures |
| |
| To Test: |
| A8 diffuse textures |
| down & upsampled draws |
| */ |
| |
| |
| |
| /** \class SkLightingShaderImpl |
| This subclass of shader applies lighting. |
| */ |
| class SkLightingShaderImpl : public SkShaderBase { |
| public: |
| /** Create a new lighting shader that uses the provided normal map and |
| lights to light the diffuse bitmap. |
| @param diffuseShader the shader that provides the diffuse colors |
| @param normalSource the source of normals for lighting computation |
| @param lights the lights applied to the geometry |
| */ |
| SkLightingShaderImpl(sk_sp<SkShader> diffuseShader, |
| sk_sp<SkNormalSource> normalSource, |
| sk_sp<SkLights> lights) |
| : fDiffuseShader(std::move(diffuseShader)) |
| , fNormalSource(std::move(normalSource)) |
| , fLights(std::move(lights)) {} |
| |
| bool isOpaque() const override; |
| |
| #if SK_SUPPORT_GPU |
| sk_sp<GrFragmentProcessor> asFragmentProcessor(const AsFPArgs&) const override; |
| #endif |
| |
| class LightingShaderContext : public Context { |
| public: |
| // The context takes ownership of the context and provider. It will call their destructors |
| // and then indirectly free their memory by calling free() on heapAllocated |
| LightingShaderContext(const SkLightingShaderImpl&, const ContextRec&, |
| SkShaderBase::Context* diffuseContext, SkNormalSource::Provider*, |
| void* heapAllocated); |
| |
| void shadeSpan(int x, int y, SkPMColor[], int count) override; |
| |
| uint32_t getFlags() const override { return fFlags; } |
| |
| private: |
| SkShaderBase::Context* fDiffuseContext; |
| SkNormalSource::Provider* fNormalProvider; |
| SkColor fPaintColor; |
| uint32_t fFlags; |
| |
| typedef Context INHERITED; |
| }; |
| |
| SK_TO_STRING_OVERRIDE() |
| SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLightingShaderImpl) |
| |
| protected: |
| void flatten(SkWriteBuffer&) const override; |
| Context* onMakeContext(const ContextRec&, SkArenaAlloc*) const override; |
| sk_sp<SkShader> onMakeColorSpace(SkColorSpaceXformer* xformer) const override; |
| |
| private: |
| sk_sp<SkShader> fDiffuseShader; |
| sk_sp<SkNormalSource> fNormalSource; |
| sk_sp<SkLights> fLights; |
| |
| friend class SkLightingShader; |
| |
| typedef SkShaderBase INHERITED; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| #if SK_SUPPORT_GPU |
| |
| #include "GrCoordTransform.h" |
| #include "GrFragmentProcessor.h" |
| #include "glsl/GrGLSLFragmentProcessor.h" |
| #include "glsl/GrGLSLFragmentShaderBuilder.h" |
| #include "glsl/GrGLSLProgramDataManager.h" |
| #include "glsl/GrGLSLUniformHandler.h" |
| #include "SkGr.h" |
| |
| // This FP expects a premul'd color input for its diffuse color. Premul'ing of the paint's color is |
| // handled by the asFragmentProcessor() factory, but shaders providing diffuse color must output it |
| // premul'd. |
| class LightingFP : public GrFragmentProcessor { |
| public: |
| static sk_sp<GrFragmentProcessor> Make(sk_sp<GrFragmentProcessor> normalFP, |
| sk_sp<SkLights> lights) { |
| return sk_sp<GrFragmentProcessor>(new LightingFP(std::move(normalFP), std::move(lights))); |
| } |
| |
| class GLSLLightingFP : public GrGLSLFragmentProcessor { |
| public: |
| GLSLLightingFP() { |
| fAmbientColor.fX = 0.0f; |
| } |
| |
| void emitCode(EmitArgs& args) override { |
| |
| GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder; |
| GrGLSLUniformHandler* uniformHandler = args.fUniformHandler; |
| const LightingFP& lightingFP = args.fFp.cast<LightingFP>(); |
| |
| const char *lightDirsUniName = nullptr; |
| const char *lightColorsUniName = nullptr; |
| if (lightingFP.fDirectionalLights.count() != 0) { |
| fLightDirsUni = uniformHandler->addUniformArray( |
| kFragment_GrShaderFlag, |
| kVec3f_GrSLType, |
| kDefault_GrSLPrecision, |
| "LightDir", |
| lightingFP.fDirectionalLights.count(), |
| &lightDirsUniName); |
| fLightColorsUni = uniformHandler->addUniformArray( |
| kFragment_GrShaderFlag, |
| kVec3f_GrSLType, |
| kDefault_GrSLPrecision, |
| "LightColor", |
| lightingFP.fDirectionalLights.count(), |
| &lightColorsUniName); |
| } |
| |
| const char* ambientColorUniName = nullptr; |
| fAmbientColorUni = uniformHandler->addUniform(kFragment_GrShaderFlag, |
| kVec3f_GrSLType, kDefault_GrSLPrecision, |
| "AmbientColor", &ambientColorUniName); |
| |
| fragBuilder->codeAppendf("vec4 diffuseColor = %s;", args.fInputColor); |
| |
| SkString dstNormalName("dstNormal"); |
| this->emitChild(0, &dstNormalName, args); |
| |
| fragBuilder->codeAppendf("vec3 normal = %s.xyz;", dstNormalName.c_str()); |
| |
| fragBuilder->codeAppend( "vec3 result = vec3(0.0);"); |
| |
| // diffuse light |
| if (lightingFP.fDirectionalLights.count() != 0) { |
| fragBuilder->codeAppendf("for (int i = 0; i < %d; i++) {", |
| lightingFP.fDirectionalLights.count()); |
| // TODO: modulate the contribution from each light based on the shadow map |
| fragBuilder->codeAppendf(" float NdotL = clamp(dot(normal, %s[i]), 0.0, 1.0);", |
| lightDirsUniName); |
| fragBuilder->codeAppendf(" result += %s[i]*diffuseColor.rgb*NdotL;", |
| lightColorsUniName); |
| fragBuilder->codeAppend("}"); |
| } |
| |
| // ambient light |
| fragBuilder->codeAppendf("result += %s * diffuseColor.rgb;", ambientColorUniName); |
| |
| // Clamping to alpha (equivalent to an unpremul'd clamp to 1.0) |
| fragBuilder->codeAppendf("%s = vec4(clamp(result.rgb, 0.0, diffuseColor.a), " |
| "diffuseColor.a);", args.fOutputColor); |
| } |
| |
| static void GenKey(const GrProcessor& proc, const GrShaderCaps&, GrProcessorKeyBuilder* b) { |
| const LightingFP& lightingFP = proc.cast<LightingFP>(); |
| b->add32(lightingFP.fDirectionalLights.count()); |
| } |
| |
| protected: |
| void onSetData(const GrGLSLProgramDataManager& pdman, |
| const GrFragmentProcessor& proc) override { |
| const LightingFP& lightingFP = proc.cast<LightingFP>(); |
| |
| const SkTArray<SkLights::Light>& directionalLights = lightingFP.directionalLights(); |
| if (directionalLights != fDirectionalLights) { |
| SkTArray<SkColor3f> lightDirs(directionalLights.count()); |
| SkTArray<SkVector3> lightColors(directionalLights.count()); |
| for (const SkLights::Light& light : directionalLights) { |
| lightDirs.push_back(light.dir()); |
| lightColors.push_back(light.color()); |
| } |
| |
| pdman.set3fv(fLightDirsUni, directionalLights.count(), &(lightDirs[0].fX)); |
| pdman.set3fv(fLightColorsUni, directionalLights.count(), &(lightColors[0].fX)); |
| |
| fDirectionalLights = directionalLights; |
| } |
| |
| const SkColor3f& ambientColor = lightingFP.ambientColor(); |
| if (ambientColor != fAmbientColor) { |
| pdman.set3fv(fAmbientColorUni, 1, &ambientColor.fX); |
| fAmbientColor = ambientColor; |
| } |
| } |
| |
| private: |
| SkTArray<SkLights::Light> fDirectionalLights; |
| GrGLSLProgramDataManager::UniformHandle fLightDirsUni; |
| GrGLSLProgramDataManager::UniformHandle fLightColorsUni; |
| |
| SkColor3f fAmbientColor; |
| GrGLSLProgramDataManager::UniformHandle fAmbientColorUni; |
| }; |
| |
| void onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override { |
| GLSLLightingFP::GenKey(*this, caps, b); |
| } |
| |
| const char* name() const override { return "LightingFP"; } |
| |
| const SkTArray<SkLights::Light>& directionalLights() const { return fDirectionalLights; } |
| const SkColor3f& ambientColor() const { return fAmbientColor; } |
| |
| private: |
| LightingFP(sk_sp<GrFragmentProcessor> normalFP, sk_sp<SkLights> lights) |
| : INHERITED(kPreservesOpaqueInput_OptimizationFlag) { |
| // fuse all ambient lights into a single one |
| fAmbientColor = lights->ambientLightColor(); |
| for (int i = 0; i < lights->numLights(); ++i) { |
| if (SkLights::Light::kDirectional_LightType == lights->light(i).type()) { |
| fDirectionalLights.push_back(lights->light(i)); |
| // TODO get the handle to the shadow map if there is one |
| } else { |
| SkDEBUGFAIL("Unimplemented Light Type passed to LightingFP"); |
| } |
| } |
| |
| this->registerChildProcessor(std::move(normalFP)); |
| this->initClassID<LightingFP>(); |
| } |
| |
| GrGLSLFragmentProcessor* onCreateGLSLInstance() const override { return new GLSLLightingFP; } |
| |
| bool onIsEqual(const GrFragmentProcessor& proc) const override { |
| const LightingFP& lightingFP = proc.cast<LightingFP>(); |
| return fDirectionalLights == lightingFP.fDirectionalLights && |
| fAmbientColor == lightingFP.fAmbientColor; |
| } |
| |
| SkTArray<SkLights::Light> fDirectionalLights; |
| SkColor3f fAmbientColor; |
| |
| typedef GrFragmentProcessor INHERITED; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| sk_sp<GrFragmentProcessor> SkLightingShaderImpl::asFragmentProcessor(const AsFPArgs& args) const { |
| sk_sp<GrFragmentProcessor> normalFP(fNormalSource->asFragmentProcessor(args)); |
| if (!normalFP) { |
| return nullptr; |
| } |
| |
| if (fDiffuseShader) { |
| sk_sp<GrFragmentProcessor> fpPipeline[] = { |
| as_SB(fDiffuseShader)->asFragmentProcessor(args), |
| LightingFP::Make(std::move(normalFP), fLights) |
| }; |
| if (!fpPipeline[0] || !fpPipeline[1]) { |
| return nullptr; |
| } |
| |
| sk_sp<GrFragmentProcessor> innerLightFP = GrFragmentProcessor::RunInSeries(fpPipeline, 2); |
| // FP is wrapped because paint's alpha needs to be applied to output |
| return GrFragmentProcessor::MulOutputByInputAlpha(std::move(innerLightFP)); |
| } else { |
| // FP is wrapped because paint comes in unpremul'd to fragment shader, but LightingFP |
| // expects premul'd color. |
| return GrFragmentProcessor::PremulInput(LightingFP::Make(std::move(normalFP), fLights)); |
| } |
| } |
| |
| #endif |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| bool SkLightingShaderImpl::isOpaque() const { |
| return (fDiffuseShader ? fDiffuseShader->isOpaque() : false); |
| } |
| |
| SkLightingShaderImpl::LightingShaderContext::LightingShaderContext( |
| const SkLightingShaderImpl& shader, const ContextRec& rec, |
| SkShaderBase::Context* diffuseContext, SkNormalSource::Provider* normalProvider, |
| void* heapAllocated) |
| : INHERITED(shader, rec) |
| , fDiffuseContext(diffuseContext) |
| , fNormalProvider(normalProvider) { |
| bool isOpaque = shader.isOpaque(); |
| |
| // update fFlags |
| uint32_t flags = 0; |
| if (isOpaque && (255 == this->getPaintAlpha())) { |
| flags |= kOpaqueAlpha_Flag; |
| } |
| |
| fPaintColor = rec.fPaint->getColor(); |
| fFlags = flags; |
| } |
| |
| static inline SkPMColor convert(SkColor3f color, U8CPU a) { |
| if (color.fX <= 0.0f) { |
| color.fX = 0.0f; |
| } else if (color.fX >= 255.0f) { |
| color.fX = 255.0f; |
| } |
| |
| if (color.fY <= 0.0f) { |
| color.fY = 0.0f; |
| } else if (color.fY >= 255.0f) { |
| color.fY = 255.0f; |
| } |
| |
| if (color.fZ <= 0.0f) { |
| color.fZ = 0.0f; |
| } else if (color.fZ >= 255.0f) { |
| color.fZ = 255.0f; |
| } |
| |
| return SkPreMultiplyARGB(a, (int) color.fX, (int) color.fY, (int) color.fZ); |
| } |
| |
| // larger is better (fewer times we have to loop), but we shouldn't |
| // take up too much stack-space (each one here costs 16 bytes) |
| #define BUFFER_MAX 16 |
| void SkLightingShaderImpl::LightingShaderContext::shadeSpan(int x, int y, |
| SkPMColor result[], int count) { |
| const SkLightingShaderImpl& lightShader = static_cast<const SkLightingShaderImpl&>(fShader); |
| |
| SkPMColor diffuse[BUFFER_MAX]; |
| SkPoint3 normals[BUFFER_MAX]; |
| |
| SkColor diffColor = fPaintColor; |
| |
| do { |
| int n = SkTMin(count, BUFFER_MAX); |
| |
| fNormalProvider->fillScanLine(x, y, normals, n); |
| |
| if (fDiffuseContext) { |
| fDiffuseContext->shadeSpan(x, y, diffuse, n); |
| } |
| |
| for (int i = 0; i < n; ++i) { |
| if (fDiffuseContext) { |
| diffColor = SkUnPreMultiply::PMColorToColor(diffuse[i]); |
| } |
| |
| SkColor3f accum = SkColor3f::Make(0.0f, 0.0f, 0.0f); |
| |
| // Adding ambient light |
| accum.fX += lightShader.fLights->ambientLightColor().fX * SkColorGetR(diffColor); |
| accum.fY += lightShader.fLights->ambientLightColor().fY * SkColorGetG(diffColor); |
| accum.fZ += lightShader.fLights->ambientLightColor().fZ * SkColorGetB(diffColor); |
| |
| // This is all done in linear unpremul color space (each component 0..255.0f though) |
| for (int l = 0; l < lightShader.fLights->numLights(); ++l) { |
| const SkLights::Light& light = lightShader.fLights->light(l); |
| |
| SkScalar illuminanceScalingFactor = 1.0f; |
| |
| if (SkLights::Light::kDirectional_LightType == light.type()) { |
| illuminanceScalingFactor = normals[i].dot(light.dir()); |
| if (illuminanceScalingFactor < 0.0f) { |
| illuminanceScalingFactor = 0.0f; |
| } |
| } |
| |
| accum.fX += light.color().fX * SkColorGetR(diffColor) * illuminanceScalingFactor; |
| accum.fY += light.color().fY * SkColorGetG(diffColor) * illuminanceScalingFactor; |
| accum.fZ += light.color().fZ * SkColorGetB(diffColor) * illuminanceScalingFactor; |
| } |
| |
| // convert() premultiplies the accumulate color with alpha |
| result[i] = convert(accum, SkColorGetA(diffColor)); |
| } |
| |
| result += n; |
| x += n; |
| count -= n; |
| } while (count > 0); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| #ifndef SK_IGNORE_TO_STRING |
| void SkLightingShaderImpl::toString(SkString* str) const { |
| str->appendf("LightingShader: ()"); |
| } |
| #endif |
| |
| sk_sp<SkFlattenable> SkLightingShaderImpl::CreateProc(SkReadBuffer& buf) { |
| |
| // Discarding SkShader flattenable params |
| bool hasLocalMatrix = buf.readBool(); |
| SkAssertResult(!hasLocalMatrix); |
| |
| sk_sp<SkLights> lights = SkLights::MakeFromBuffer(buf); |
| |
| sk_sp<SkNormalSource> normalSource(buf.readFlattenable<SkNormalSource>()); |
| |
| bool hasDiffuse = buf.readBool(); |
| sk_sp<SkShader> diffuseShader = nullptr; |
| if (hasDiffuse) { |
| diffuseShader = buf.readFlattenable<SkShaderBase>(); |
| } |
| |
| return sk_make_sp<SkLightingShaderImpl>(std::move(diffuseShader), std::move(normalSource), |
| std::move(lights)); |
| } |
| |
| void SkLightingShaderImpl::flatten(SkWriteBuffer& buf) const { |
| this->INHERITED::flatten(buf); |
| |
| fLights->flatten(buf); |
| |
| buf.writeFlattenable(fNormalSource.get()); |
| buf.writeBool(fDiffuseShader); |
| if (fDiffuseShader) { |
| buf.writeFlattenable(fDiffuseShader.get()); |
| } |
| } |
| |
| SkShaderBase::Context* SkLightingShaderImpl::onMakeContext( |
| const ContextRec& rec, SkArenaAlloc* alloc) const |
| { |
| SkShaderBase::Context *diffuseContext = nullptr; |
| if (fDiffuseShader) { |
| diffuseContext = as_SB(fDiffuseShader)->makeContext(rec, alloc); |
| if (!diffuseContext) { |
| return nullptr; |
| } |
| } |
| |
| SkNormalSource::Provider* normalProvider = fNormalSource->asProvider(rec, alloc); |
| if (!normalProvider) { |
| return nullptr; |
| } |
| |
| return alloc->make<LightingShaderContext>(*this, rec, diffuseContext, normalProvider, nullptr); |
| } |
| |
| sk_sp<SkShader> SkLightingShaderImpl::onMakeColorSpace(SkColorSpaceXformer* xformer) const { |
| sk_sp<SkShader> xformedDiffuseShader = |
| fDiffuseShader ? xformer->apply(fDiffuseShader.get()) : nullptr; |
| return SkLightingShader::Make(std::move(xformedDiffuseShader), fNormalSource, |
| fLights->makeColorSpace(xformer)); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| sk_sp<SkShader> SkLightingShader::Make(sk_sp<SkShader> diffuseShader, |
| sk_sp<SkNormalSource> normalSource, |
| sk_sp<SkLights> lights) { |
| SkASSERT(lights); |
| if (!normalSource) { |
| normalSource = SkNormalSource::MakeFlat(); |
| } |
| |
| return sk_make_sp<SkLightingShaderImpl>(std::move(diffuseShader), std::move(normalSource), |
| std::move(lights)); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkLightingShader) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLightingShaderImpl) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END |
| |
| /////////////////////////////////////////////////////////////////////////////// |