diff options
Diffstat (limited to 'src/core/SkLightingShader.cpp')
| -rw-r--r-- | src/core/SkLightingShader.cpp | 738 |
1 files changed, 738 insertions, 0 deletions
diff --git a/src/core/SkLightingShader.cpp b/src/core/SkLightingShader.cpp new file mode 100644 index 0000000000..ce5c0ddb25 --- /dev/null +++ b/src/core/SkLightingShader.cpp @@ -0,0 +1,738 @@ + +/* + * 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 "SkBitmapProcState.h" +#include "SkColor.h" +#include "SkEmptyShader.h" +#include "SkErrorInternals.h" +#include "SkLightingShader.h" +#include "SkMathPriv.h" +#include "SkPoint3.h" +#include "SkReadBuffer.h" +#include "SkWriteBuffer.h" + +//////////////////////////////////////////////////////////////////////////// + +/* + SkLightingShader TODOs: + support other than clamp mode + allow 'diffuse' & 'normal' to be of different dimensions? + support different light types + support multiple lights + enforce normal map is 4 channel + use SkImages instead if SkBitmaps + + To Test: + non-opaque diffuse textures + A8 diffuse textures + down & upsampled draws +*/ + + + +/** \class SkLightingShaderImpl + This subclass of shader applies lighting. +*/ +class SK_API SkLightingShaderImpl : public SkShader { +public: + + /** Create a new lighting shader that uses the provided normal map and + lights to light the diffuse bitmap. + @param diffuse the diffuse bitmap + @param normal the normal map + @param lights the lights applied to the normal map + @param invNormRotation rotation applied to the normal map's normals + @param diffLocalM the local matrix for the diffuse coordinates + @param normLocalM the local matrix for the normal coordinates + */ + SkLightingShaderImpl(const SkBitmap& diffuse, const SkBitmap& normal, + const SkLightingShader::Lights* lights, + const SkVector& invNormRotation, + const SkMatrix* diffLocalM, const SkMatrix* normLocalM) + : INHERITED(diffLocalM) + , fDiffuseMap(diffuse) + , fNormalMap(normal) + , fLights(SkRef(lights)) + , fInvNormRotation(invNormRotation) { + + if (normLocalM) { + fNormLocalMatrix = *normLocalM; + } else { + fNormLocalMatrix.reset(); + } + // Pre-cache so future calls to fNormLocalMatrix.getType() are threadsafe. + (void)fNormLocalMatrix.getType(); + + } + + bool isOpaque() const override; + + bool asFragmentProcessor(GrContext*, const SkPaint& paint, const SkMatrix& viewM, + const SkMatrix* localMatrix, GrColor* color, + GrProcessorDataManager*, GrFragmentProcessor** fp) const override; + + size_t contextSize() const override; + + class LightingShaderContext : public SkShader::Context { + public: + // The context takes ownership of the states. It will call their destructors + // but will NOT free the memory. + LightingShaderContext(const SkLightingShaderImpl&, const ContextRec&, + SkBitmapProcState* diffuseState, SkBitmapProcState* normalState); + ~LightingShaderContext() override; + + void shadeSpan(int x, int y, SkPMColor[], int count) override; + + uint32_t getFlags() const override { return fFlags; } + + private: + SkBitmapProcState* fDiffuseState; + SkBitmapProcState* fNormalState; + uint32_t fFlags; + + typedef SkShader::Context INHERITED; + }; + + SK_TO_STRING_OVERRIDE() + SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLightingShaderImpl) + +protected: + void flatten(SkWriteBuffer&) const override; + Context* onCreateContext(const ContextRec&, void*) const override; + bool computeNormTotalInverse(const ContextRec& rec, SkMatrix* normTotalInverse) const; + +private: + SkBitmap fDiffuseMap; + SkBitmap fNormalMap; + + SkAutoTUnref<const SkLightingShader::Lights> fLights; + + SkMatrix fNormLocalMatrix; + SkVector fInvNormRotation; + + friend class SkLightingShader; + + typedef SkShader INHERITED; +}; + +//////////////////////////////////////////////////////////////////////////// + +#if SK_SUPPORT_GPU + +#include "GrCoordTransform.h" +#include "GrFragmentProcessor.h" +#include "GrTextureAccess.h" +#include "gl/GrGLProcessor.h" +#include "gl/builders/GrGLProgramBuilder.h" +#include "SkGr.h" + +class LightingFP : public GrFragmentProcessor { +public: + LightingFP(GrProcessorDataManager* pdm, GrTexture* diffuse, GrTexture* normal, + const SkMatrix& diffMatrix, const SkMatrix& normMatrix, + const GrTextureParams& diffParams, const GrTextureParams& normParams, + const SkLightingShader::Lights* lights, const SkVector& invNormRotation) + : fDiffDeviceTransform(kLocal_GrCoordSet, diffMatrix, diffuse, diffParams.filterMode()) + , fNormDeviceTransform(kLocal_GrCoordSet, normMatrix, normal, normParams.filterMode()) + , fDiffuseTextureAccess(diffuse, diffParams) + , fNormalTextureAccess(normal, normParams) + , fInvNormRotation(invNormRotation) { + this->addCoordTransform(&fDiffDeviceTransform); + this->addCoordTransform(&fNormDeviceTransform); + this->addTextureAccess(&fDiffuseTextureAccess); + this->addTextureAccess(&fNormalTextureAccess); + + // fuse all ambient lights into a single one + fAmbientColor.set(0.0f, 0.0f, 0.0f); + for (int i = 0; i < lights->numLights(); ++i) { + if (SkLight::kAmbient_LightType == lights->light(i).type()) { + fAmbientColor += lights->light(i).color(); + } else { + // TODO: handle more than one of these + fLightColor = lights->light(i).color(); + fLightDir = lights->light(i).dir(); + } + } + + this->initClassID<LightingFP>(); + } + + class LightingGLFP : public GrGLFragmentProcessor { + public: + LightingGLFP() { + fLightDir.fX = 10000.0f; + fLightColor.fX = 0.0f; + fAmbientColor.fX = 0.0f; + fInvNormRotation.fX = 0.0f; + } + + void emitCode(EmitArgs& args) override { + + GrGLFragmentBuilder* fpb = args.fBuilder->getFragmentShaderBuilder(); + + // add uniforms + const char* lightDirUniName = NULL; + fLightDirUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, + kVec3f_GrSLType, kDefault_GrSLPrecision, + "LightDir", &lightDirUniName); + + const char* lightColorUniName = NULL; + fLightColorUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, + kVec3f_GrSLType, kDefault_GrSLPrecision, + "LightColor", &lightColorUniName); + + const char* ambientColorUniName = NULL; + fAmbientColorUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, + kVec3f_GrSLType, kDefault_GrSLPrecision, + "AmbientColor", &ambientColorUniName); + + const char* xformUniName = NULL; + fXformUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, + kVec2f_GrSLType, kDefault_GrSLPrecision, + "Xform", &xformUniName); + + fpb->codeAppend("vec4 diffuseColor = "); + fpb->appendTextureLookupAndModulate(args.fInputColor, args.fSamplers[0], + args.fCoords[0].c_str(), + args.fCoords[0].getType()); + fpb->codeAppend(";"); + + fpb->codeAppend("vec4 normalColor = "); + fpb->appendTextureLookup(args.fSamplers[1], + args.fCoords[1].c_str(), + args.fCoords[1].getType()); + fpb->codeAppend(";"); + + fpb->codeAppend("vec3 normal = normalColor.rgb - vec3(0.5);"); + + fpb->codeAppendf("mat3 m = mat3(%s.x, -%s.y, 0.0, %s.y, %s.x, 0.0, 0.0, 0.0, 1.0);", + xformUniName, xformUniName, xformUniName, xformUniName); + + // TODO: inverse map the light direction vectors in the vertex shader rather than + // transforming all the normals here! + fpb->codeAppend("normal = normalize(m*normal);"); + + fpb->codeAppendf("float NdotL = clamp(dot(normal, %s), 0.0, 1.0);", lightDirUniName); + // diffuse light + fpb->codeAppendf("vec3 result = %s*diffuseColor.rgb*NdotL;", lightColorUniName); + // ambient light + fpb->codeAppendf("result += %s;", ambientColorUniName); + fpb->codeAppendf("%s = vec4(result.rgb, diffuseColor.a);", args.fOutputColor); + } + + static void GenKey(const GrProcessor& proc, const GrGLSLCaps&, + GrProcessorKeyBuilder* b) { +// const LightingFP& lightingFP = proc.cast<LightingFP>(); + // only one shader generated currently + b->add32(0x0); + } + + protected: + void onSetData(const GrGLProgramDataManager& pdman, const GrProcessor& proc) override { + const LightingFP& lightingFP = proc.cast<LightingFP>(); + + const SkVector3& lightDir = lightingFP.lightDir(); + if (lightDir != fLightDir) { + pdman.set3fv(fLightDirUni, 1, &lightDir.fX); + fLightDir = lightDir; + } + + const SkColor3f& lightColor = lightingFP.lightColor(); + if (lightColor != fLightColor) { + pdman.set3fv(fLightColorUni, 1, &lightColor.fX); + fLightColor = lightColor; + } + + const SkColor3f& ambientColor = lightingFP.ambientColor(); + if (ambientColor != fAmbientColor) { + pdman.set3fv(fAmbientColorUni, 1, &ambientColor.fX); + fAmbientColor = ambientColor; + } + + const SkVector& invNormRotation = lightingFP.invNormRotation(); + if (invNormRotation != fInvNormRotation) { + pdman.set2fv(fXformUni, 1, &invNormRotation.fX); + fInvNormRotation = invNormRotation; + } + } + + private: + SkVector3 fLightDir; + GrGLProgramDataManager::UniformHandle fLightDirUni; + + SkColor3f fLightColor; + GrGLProgramDataManager::UniformHandle fLightColorUni; + + SkColor3f fAmbientColor; + GrGLProgramDataManager::UniformHandle fAmbientColorUni; + + SkVector fInvNormRotation; + GrGLProgramDataManager::UniformHandle fXformUni; + }; + + void onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const override { + LightingGLFP::GenKey(*this, caps, b); + } + + const char* name() const override { return "LightingFP"; } + + void onComputeInvariantOutput(GrInvariantOutput* inout) const override { + inout->mulByUnknownFourComponents(); + } + + const SkVector3& lightDir() const { return fLightDir; } + const SkColor3f& lightColor() const { return fLightColor; } + const SkColor3f& ambientColor() const { return fAmbientColor; } + const SkVector& invNormRotation() const { return fInvNormRotation; } + +private: + GrGLFragmentProcessor* onCreateGLInstance() const override { return SkNEW(LightingGLFP); } + + bool onIsEqual(const GrFragmentProcessor& proc) const override { + const LightingFP& lightingFP = proc.cast<LightingFP>(); + return fDiffDeviceTransform == lightingFP.fDiffDeviceTransform && + fNormDeviceTransform == lightingFP.fNormDeviceTransform && + fDiffuseTextureAccess == lightingFP.fDiffuseTextureAccess && + fNormalTextureAccess == lightingFP.fNormalTextureAccess && + fLightDir == lightingFP.fLightDir && + fLightColor == lightingFP.fLightColor && + fAmbientColor == lightingFP.fAmbientColor && + fInvNormRotation == lightingFP.fInvNormRotation; + } + + GrCoordTransform fDiffDeviceTransform; + GrCoordTransform fNormDeviceTransform; + GrTextureAccess fDiffuseTextureAccess; + GrTextureAccess fNormalTextureAccess; + SkVector3 fLightDir; + SkColor3f fLightColor; + SkColor3f fAmbientColor; + + SkVector fInvNormRotation; +}; + +//////////////////////////////////////////////////////////////////////////// + +static bool make_mat(const SkBitmap& bm, + const SkMatrix& localMatrix1, + const SkMatrix* localMatrix2, + SkMatrix* result) { + + result->setIDiv(bm.width(), bm.height()); + + SkMatrix lmInverse; + if (!localMatrix1.invert(&lmInverse)) { + return false; + } + if (localMatrix2) { + SkMatrix inv; + if (!localMatrix2->invert(&inv)) { + return false; + } + lmInverse.postConcat(inv); + } + result->preConcat(lmInverse); + + return true; +} + +bool SkLightingShaderImpl::asFragmentProcessor(GrContext* context, const SkPaint& paint, + const SkMatrix& viewM, const SkMatrix* localMatrix, + GrColor* color, GrProcessorDataManager* pdm, + GrFragmentProcessor** fp) const { + // we assume diffuse and normal maps have same width and height + // TODO: support different sizes + SkASSERT(fDiffuseMap.width() == fNormalMap.width() && + fDiffuseMap.height() == fNormalMap.height()); + SkMatrix diffM, normM; + + if (!make_mat(fDiffuseMap, this->getLocalMatrix(), localMatrix, &diffM)) { + return false; + } + + if (!make_mat(fNormalMap, fNormLocalMatrix, localMatrix, &normM)) { + return false; + } + + bool doBicubic; + GrTextureParams::FilterMode diffFilterMode = GrSkFilterQualityToGrFilterMode( + SkTMin(paint.getFilterQuality(), kMedium_SkFilterQuality), + viewM, + this->getLocalMatrix(), + &doBicubic); + SkASSERT(!doBicubic); + + GrTextureParams::FilterMode normFilterMode = GrSkFilterQualityToGrFilterMode( + SkTMin(paint.getFilterQuality(), kMedium_SkFilterQuality), + viewM, + fNormLocalMatrix, + &doBicubic); + SkASSERT(!doBicubic); + + // TODO: support other tile modes + GrTextureParams diffParams(kClamp_TileMode, diffFilterMode); + SkAutoTUnref<GrTexture> diffuseTexture(GrRefCachedBitmapTexture(context, + fDiffuseMap, &diffParams)); + if (!diffuseTexture) { + SkErrorInternals::SetError(kInternalError_SkError, + "Couldn't convert bitmap to texture."); + return false; + } + + GrTextureParams normParams(kClamp_TileMode, normFilterMode); + SkAutoTUnref<GrTexture> normalTexture(GrRefCachedBitmapTexture(context, + fNormalMap, &normParams)); + if (!normalTexture) { + SkErrorInternals::SetError(kInternalError_SkError, + "Couldn't convert bitmap to texture."); + return false; + } + + + *fp = SkNEW_ARGS(LightingFP, (pdm, diffuseTexture, normalTexture, + diffM, normM, diffParams, normParams, fLights, + fInvNormRotation)); + + *color = GrColorPackA4(paint.getAlpha()); + return true; +} +#else + +bool SkLightingShaderImpl::asFragmentProcessor(GrContext* context, const SkPaint& paint, + const SkMatrix& viewM, const SkMatrix* localMatrix, + GrColor* color, GrProcessorDataManager*, + GrFragmentProcessor** fp) const { + SkDEBUGFAIL("Should not call in GPU-less build"); + return false; +} + +#endif + +//////////////////////////////////////////////////////////////////////////// + +bool SkLightingShaderImpl::isOpaque() const { + return fDiffuseMap.isOpaque(); +} + +size_t SkLightingShaderImpl::contextSize() const { + return 2 * sizeof(SkBitmapProcState) + sizeof(LightingShaderContext); +} + +SkLightingShaderImpl::LightingShaderContext::LightingShaderContext(const SkLightingShaderImpl& shader, + const ContextRec& rec, + SkBitmapProcState* diffuseState, + SkBitmapProcState* normalState) + : INHERITED(shader, rec) + , fDiffuseState(diffuseState) + , fNormalState(normalState) +{ + const SkPixmap& pixmap = fDiffuseState->fPixmap; + bool isOpaque = pixmap.isOpaque(); + + // update fFlags + uint32_t flags = 0; + if (isOpaque && (255 == this->getPaintAlpha())) { + flags |= kOpaqueAlpha_Flag; + } + + fFlags = flags; +} + +SkLightingShaderImpl::LightingShaderContext::~LightingShaderContext() { + // The bitmap proc states have been created outside of the context on memory that will be freed + // elsewhere. Call the destructors but leave the freeing of the memory to the caller. + fDiffuseState->~SkBitmapProcState(); + fNormalState->~SkBitmapProcState(); +} + +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 TMP_COUNT 16 + +void SkLightingShaderImpl::LightingShaderContext::shadeSpan(int x, int y, + SkPMColor result[], int count) { + const SkLightingShaderImpl& lightShader = static_cast<const SkLightingShaderImpl&>(fShader); + + uint32_t tmpColor[TMP_COUNT], tmpNormal[TMP_COUNT]; + SkPMColor tmpColor2[2*TMP_COUNT], tmpNormal2[2*TMP_COUNT]; + + SkBitmapProcState::MatrixProc diffMProc = fDiffuseState->getMatrixProc(); + SkBitmapProcState::SampleProc32 diffSProc = fDiffuseState->getSampleProc32(); + + SkBitmapProcState::MatrixProc normalMProc = fNormalState->getMatrixProc(); + SkBitmapProcState::SampleProc32 normalSProc = fNormalState->getSampleProc32(); + + int diffMax = fDiffuseState->maxCountForBufferSize(sizeof(tmpColor[0]) * TMP_COUNT); + int normMax = fNormalState->maxCountForBufferSize(sizeof(tmpNormal[0]) * TMP_COUNT); + int max = SkTMin(diffMax, normMax); + + SkASSERT(fDiffuseState->fPixmap.addr()); + SkASSERT(fNormalState->fPixmap.addr()); + + SkPoint3 norm, xformedNorm; + + do { + int n = count; + if (n > max) { + n = max; + } + + diffMProc(*fDiffuseState, tmpColor, n, x, y); + diffSProc(*fDiffuseState, tmpColor, n, tmpColor2); + + normalMProc(*fNormalState, tmpNormal, n, x, y); + normalSProc(*fNormalState, tmpNormal, n, tmpNormal2); + + for (int i = 0; i < n; ++i) { + SkASSERT(0xFF == SkColorGetA(tmpNormal2[i])); // opaque -> unpremul + norm.set(SkIntToScalar(SkGetPackedR32(tmpNormal2[i]))-127.0f, + SkIntToScalar(SkGetPackedG32(tmpNormal2[i]))-127.0f, + SkIntToScalar(SkGetPackedB32(tmpNormal2[i]))-127.0f); + norm.normalize(); + + xformedNorm.fX = lightShader.fInvNormRotation.fX * norm.fX + + lightShader.fInvNormRotation.fY * norm.fY; + xformedNorm.fY = lightShader.fInvNormRotation.fX * norm.fX - + lightShader.fInvNormRotation.fY * norm.fY; + xformedNorm.fZ = norm.fZ; + + SkColor diffColor = SkUnPreMultiply::PMColorToColor(tmpColor2[i]); + + SkColor3f accum = SkColor3f::Make(0.0f, 0.0f, 0.0f); + // 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 SkLight& light = lightShader.fLights->light(l); + + if (SkLight::kAmbient_LightType == light.type()) { + accum += light.color().makeScale(255.0f); + } else { + SkScalar NdotL = xformedNorm.dot(light.dir()); + if (NdotL < 0.0f) { + NdotL = 0.0f; + } + + accum.fX += light.color().fX * SkColorGetR(diffColor) * NdotL; + accum.fY += light.color().fY * SkColorGetG(diffColor) * NdotL; + accum.fZ += light.color().fZ * SkColorGetB(diffColor) * NdotL; + } + } + + 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 + +SkFlattenable* SkLightingShaderImpl::CreateProc(SkReadBuffer& buf) { + SkMatrix diffLocalM; + bool hasDiffLocalM = buf.readBool(); + if (hasDiffLocalM) { + buf.readMatrix(&diffLocalM); + } else { + diffLocalM.reset(); + } + + SkMatrix normLocalM; + bool hasNormLocalM = buf.readBool(); + if (hasNormLocalM) { + buf.readMatrix(&normLocalM); + } else { + normLocalM.reset(); + } + + SkBitmap diffuse; + if (!buf.readBitmap(&diffuse)) { + return NULL; + } + diffuse.setImmutable(); + + SkBitmap normal; + if (!buf.readBitmap(&normal)) { + return NULL; + } + normal.setImmutable(); + + int numLights = buf.readInt(); + + SkLightingShader::Lights::Builder builder; + + for (int l = 0; l < numLights; ++l) { + bool isAmbient = buf.readBool(); + + SkColor3f color; + if (!buf.readScalarArray(&color.fX, 3)) { + return NULL; + } + + if (isAmbient) { + builder.add(SkLight(color)); + } else { + SkVector3 dir; + if (!buf.readScalarArray(&dir.fX, 3)) { + return NULL; + } + builder.add(SkLight(color, dir)); + } + } + + SkAutoTUnref<const SkLightingShader::Lights> lights(builder.finish()); + + return SkNEW_ARGS(SkLightingShaderImpl, (diffuse, normal, lights, + SkVector::Make(1.0f, 0.0f), + &diffLocalM, &normLocalM)); +} + +void SkLightingShaderImpl::flatten(SkWriteBuffer& buf) const { + this->INHERITED::flatten(buf); + + bool hasNormLocalM = !fNormLocalMatrix.isIdentity(); + buf.writeBool(hasNormLocalM); + if (hasNormLocalM) { + buf.writeMatrix(fNormLocalMatrix); + } + + buf.writeBitmap(fDiffuseMap); + buf.writeBitmap(fNormalMap); + + buf.writeInt(fLights->numLights()); + for (int l = 0; l < fLights->numLights(); ++l) { + const SkLight& light = fLights->light(l); + + bool isAmbient = SkLight::kAmbient_LightType == light.type(); + + buf.writeBool(isAmbient); + buf.writeScalarArray(&light.color().fX, 3); + if (!isAmbient) { + buf.writeScalarArray(&light.dir().fX, 3); + } + } +} + +bool SkLightingShaderImpl::computeNormTotalInverse(const ContextRec& rec, + SkMatrix* normTotalInverse) const { + SkMatrix total; + total.setConcat(*rec.fMatrix, fNormLocalMatrix); + + const SkMatrix* m = &total; + if (rec.fLocalMatrix) { + total.setConcat(*m, *rec.fLocalMatrix); + m = &total; + } + return m->invert(normTotalInverse); +} + +SkShader::Context* SkLightingShaderImpl::onCreateContext(const ContextRec& rec, + void* storage) const { + + SkMatrix diffTotalInv; + // computeTotalInverse was called in SkShader::createContext so we know it will succeed + SkAssertResult(this->computeTotalInverse(rec, &diffTotalInv)); + + SkMatrix normTotalInv; + if (!this->computeNormTotalInverse(rec, &normTotalInv)) { + return NULL; + } + + void* diffuseStateStorage = (char*)storage + sizeof(LightingShaderContext); + SkBitmapProcState* diffuseState = SkNEW_PLACEMENT(diffuseStateStorage, SkBitmapProcState); + SkASSERT(diffuseState); + + diffuseState->fTileModeX = SkShader::kClamp_TileMode; + diffuseState->fTileModeY = SkShader::kClamp_TileMode; + diffuseState->fOrigBitmap = fDiffuseMap; + if (!diffuseState->chooseProcs(diffTotalInv, *rec.fPaint)) { + diffuseState->~SkBitmapProcState(); + return NULL; + } + + void* normalStateStorage = (char*)storage + sizeof(LightingShaderContext) + sizeof(SkBitmapProcState); + SkBitmapProcState* normalState = SkNEW_PLACEMENT(normalStateStorage, SkBitmapProcState); + SkASSERT(normalState); + + normalState->fTileModeX = SkShader::kClamp_TileMode; + normalState->fTileModeY = SkShader::kClamp_TileMode; + normalState->fOrigBitmap = fNormalMap; + if (!normalState->chooseProcs(normTotalInv, *rec.fPaint)) { + diffuseState->~SkBitmapProcState(); + normalState->~SkBitmapProcState(); + return NULL; + } + + return SkNEW_PLACEMENT_ARGS(storage, LightingShaderContext, (*this, rec, + diffuseState, normalState)); +} + +/////////////////////////////////////////////////////////////////////////////// + +static bool bitmap_is_too_big(const SkBitmap& bm) { + // SkBitmapProcShader stores bitmap coordinates in a 16bit buffer, as it + // communicates between its matrix-proc and its sampler-proc. Until we can + // widen that, we have to reject bitmaps that are larger. + // + static const int kMaxSize = 65535; + + return bm.width() > kMaxSize || bm.height() > kMaxSize; +} + +SkShader* SkLightingShader::Create(const SkBitmap& diffuse, const SkBitmap& normal, + const Lights* lights, + const SkVector& invNormRotation, + const SkMatrix* diffLocalM, const SkMatrix* normLocalM) { + if (diffuse.isNull() || bitmap_is_too_big(diffuse) || + normal.isNull() || bitmap_is_too_big(normal) || + diffuse.width() != normal.width() || + diffuse.height() != normal.height()) { + return nullptr; + } + + SkASSERT(SkScalarNearlyEqual(invNormRotation.lengthSqd(), SK_Scalar1)); + + return SkNEW_ARGS(SkLightingShaderImpl, (diffuse, normal, lights, + invNormRotation, diffLocalM, normLocalM)); +} + +/////////////////////////////////////////////////////////////////////////////// + +SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkLightingShader) + SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLightingShaderImpl) +SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END + +/////////////////////////////////////////////////////////////////////////////// |