| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrBicubicEffect.h" |
| #include "GrInvariantOutput.h" |
| #include "gl/builders/GrGLProgramBuilder.h" |
| |
| #define DS(x) SkDoubleToScalar(x) |
| |
| const SkScalar GrBicubicEffect::gMitchellCoefficients[16] = { |
| DS( 1.0 / 18.0), DS(-9.0 / 18.0), DS( 15.0 / 18.0), DS( -7.0 / 18.0), |
| DS(16.0 / 18.0), DS( 0.0 / 18.0), DS(-36.0 / 18.0), DS( 21.0 / 18.0), |
| DS( 1.0 / 18.0), DS( 9.0 / 18.0), DS( 27.0 / 18.0), DS(-21.0 / 18.0), |
| DS( 0.0 / 18.0), DS( 0.0 / 18.0), DS( -6.0 / 18.0), DS( 7.0 / 18.0), |
| }; |
| |
| |
| class GrGLBicubicEffect : public GrGLFragmentProcessor { |
| public: |
| GrGLBicubicEffect(const GrProcessor&); |
| |
| virtual void emitCode(EmitArgs&) override; |
| |
| static inline void GenKey(const GrProcessor& effect, const GrGLSLCaps&, |
| GrProcessorKeyBuilder* b) { |
| const GrTextureDomain& domain = effect.cast<GrBicubicEffect>().domain(); |
| b->add32(GrTextureDomain::GLDomain::DomainKey(domain)); |
| } |
| |
| protected: |
| void onSetData(const GrGLProgramDataManager&, const GrProcessor&) override; |
| |
| private: |
| typedef GrGLProgramDataManager::UniformHandle UniformHandle; |
| |
| UniformHandle fCoefficientsUni; |
| UniformHandle fImageIncrementUni; |
| GrTextureDomain::GLDomain fDomain; |
| |
| typedef GrGLFragmentProcessor INHERITED; |
| }; |
| |
| GrGLBicubicEffect::GrGLBicubicEffect(const GrProcessor&) { |
| } |
| |
| void GrGLBicubicEffect::emitCode(EmitArgs& args) { |
| const GrTextureDomain& domain = args.fFp.cast<GrBicubicEffect>().domain(); |
| |
| fCoefficientsUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, |
| kMat44f_GrSLType, kDefault_GrSLPrecision, |
| "Coefficients"); |
| fImageIncrementUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility, |
| kVec2f_GrSLType, kDefault_GrSLPrecision, |
| "ImageIncrement"); |
| |
| const char* imgInc = args.fBuilder->getUniformCStr(fImageIncrementUni); |
| const char* coeff = args.fBuilder->getUniformCStr(fCoefficientsUni); |
| |
| SkString cubicBlendName; |
| |
| static const GrGLShaderVar gCubicBlendArgs[] = { |
| GrGLShaderVar("coefficients", kMat44f_GrSLType), |
| GrGLShaderVar("t", kFloat_GrSLType), |
| GrGLShaderVar("c0", kVec4f_GrSLType), |
| GrGLShaderVar("c1", kVec4f_GrSLType), |
| GrGLShaderVar("c2", kVec4f_GrSLType), |
| GrGLShaderVar("c3", kVec4f_GrSLType), |
| }; |
| GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder(); |
| SkString coords2D = fsBuilder->ensureFSCoords2D(args.fCoords, 0); |
| fsBuilder->emitFunction(kVec4f_GrSLType, |
| "cubicBlend", |
| SK_ARRAY_COUNT(gCubicBlendArgs), |
| gCubicBlendArgs, |
| "\tvec4 ts = vec4(1.0, t, t * t, t * t * t);\n" |
| "\tvec4 c = coefficients * ts;\n" |
| "\treturn c.x * c0 + c.y * c1 + c.z * c2 + c.w * c3;\n", |
| &cubicBlendName); |
| fsBuilder->codeAppendf("\tvec2 coord = %s - %s * vec2(0.5);\n", coords2D.c_str(), imgInc); |
| // We unnormalize the coord in order to determine our fractional offset (f) within the texel |
| // We then snap coord to a texel center and renormalize. The snap prevents cases where the |
| // starting coords are near a texel boundary and accumulations of imgInc would cause us to skip/ |
| // double hit a texel. |
| fsBuilder->codeAppendf("\tcoord /= %s;\n", imgInc); |
| fsBuilder->codeAppend("\tvec2 f = fract(coord);\n"); |
| fsBuilder->codeAppendf("\tcoord = (coord - f + vec2(0.5)) * %s;\n", imgInc); |
| fsBuilder->codeAppend("\tvec4 rowColors[4];\n"); |
| for (int y = 0; y < 4; ++y) { |
| for (int x = 0; x < 4; ++x) { |
| SkString coord; |
| coord.printf("coord + %s * vec2(%d, %d)", imgInc, x - 1, y - 1); |
| SkString sampleVar; |
| sampleVar.printf("rowColors[%d]", x); |
| fDomain.sampleTexture(fsBuilder, domain, sampleVar.c_str(), coord, args.fSamplers[0]); |
| } |
| fsBuilder->codeAppendf("\tvec4 s%d = %s(%s, f.x, rowColors[0], rowColors[1], rowColors[2], rowColors[3]);\n", y, cubicBlendName.c_str(), coeff); |
| } |
| SkString bicubicColor; |
| bicubicColor.printf("%s(%s, f.y, s0, s1, s2, s3)", cubicBlendName.c_str(), coeff); |
| fsBuilder->codeAppendf("\t%s = %s;\n", args.fOutputColor,(GrGLSLExpr4(bicubicColor.c_str()) * |
| GrGLSLExpr4(args.fInputColor)).c_str()); |
| } |
| |
| void GrGLBicubicEffect::onSetData(const GrGLProgramDataManager& pdman, |
| const GrProcessor& processor) { |
| const GrBicubicEffect& bicubicEffect = processor.cast<GrBicubicEffect>(); |
| const GrTexture& texture = *processor.texture(0); |
| float imageIncrement[2]; |
| imageIncrement[0] = 1.0f / texture.width(); |
| imageIncrement[1] = 1.0f / texture.height(); |
| pdman.set2fv(fImageIncrementUni, 1, imageIncrement); |
| pdman.setMatrix4f(fCoefficientsUni, bicubicEffect.coefficients()); |
| fDomain.setData(pdman, bicubicEffect.domain(), texture.origin()); |
| } |
| |
| static inline void convert_row_major_scalar_coeffs_to_column_major_floats(float dst[16], |
| const SkScalar src[16]) { |
| for (int y = 0; y < 4; y++) { |
| for (int x = 0; x < 4; x++) { |
| dst[x * 4 + y] = SkScalarToFloat(src[y * 4 + x]); |
| } |
| } |
| } |
| |
| GrBicubicEffect::GrBicubicEffect(GrProcessorDataManager* procDataManager, |
| GrTexture* texture, |
| const SkScalar coefficients[16], |
| const SkMatrix &matrix, |
| const SkShader::TileMode tileModes[2]) |
| : INHERITED(procDataManager, texture, matrix, |
| GrTextureParams(tileModes, GrTextureParams::kNone_FilterMode)) |
| , fDomain(GrTextureDomain::IgnoredDomain()) { |
| this->initClassID<GrBicubicEffect>(); |
| convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients); |
| } |
| |
| GrBicubicEffect::GrBicubicEffect(GrProcessorDataManager* procDataManager, |
| GrTexture* texture, |
| const SkScalar coefficients[16], |
| const SkMatrix &matrix, |
| const SkRect& domain) |
| : INHERITED(procDataManager, texture, matrix, |
| GrTextureParams(SkShader::kClamp_TileMode, GrTextureParams::kNone_FilterMode)) |
| , fDomain(domain, GrTextureDomain::kClamp_Mode) { |
| this->initClassID<GrBicubicEffect>(); |
| convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients); |
| } |
| |
| GrBicubicEffect::~GrBicubicEffect() { |
| } |
| |
| void GrBicubicEffect::onGetGLProcessorKey(const GrGLSLCaps& caps, |
| GrProcessorKeyBuilder* b) const { |
| GrGLBicubicEffect::GenKey(*this, caps, b); |
| } |
| |
| GrGLFragmentProcessor* GrBicubicEffect::onCreateGLInstance() const { |
| return SkNEW_ARGS(GrGLBicubicEffect, (*this)); |
| } |
| |
| bool GrBicubicEffect::onIsEqual(const GrFragmentProcessor& sBase) const { |
| const GrBicubicEffect& s = sBase.cast<GrBicubicEffect>(); |
| return !memcmp(fCoefficients, s.coefficients(), 16) && |
| fDomain == s.fDomain; |
| } |
| |
| void GrBicubicEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const { |
| // FIXME: Perhaps we can do better. |
| inout->mulByUnknownSingleComponent(); |
| } |
| |
| GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrBicubicEffect); |
| |
| GrFragmentProcessor* GrBicubicEffect::TestCreate(GrProcessorTestData* d) { |
| int texIdx = d->fRandom->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx : |
| GrProcessorUnitTest::kAlphaTextureIdx; |
| SkScalar coefficients[16]; |
| for (int i = 0; i < 16; i++) { |
| coefficients[i] = d->fRandom->nextSScalar1(); |
| } |
| return GrBicubicEffect::Create(d->fProcDataManager, d->fTextures[texIdx], coefficients); |
| } |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrBicubicEffect::ShouldUseBicubic(const SkMatrix& matrix, |
| GrTextureParams::FilterMode* filterMode) { |
| if (matrix.isIdentity()) { |
| *filterMode = GrTextureParams::kNone_FilterMode; |
| return false; |
| } |
| |
| SkScalar scales[2]; |
| if (!matrix.getMinMaxScales(scales) || scales[0] < SK_Scalar1) { |
| // Bicubic doesn't handle arbitrary minimization well, as src texels can be skipped |
| // entirely, |
| *filterMode = GrTextureParams::kMipMap_FilterMode; |
| return false; |
| } |
| // At this point if scales[1] == SK_Scalar1 then the matrix doesn't do any scaling. |
| if (scales[1] == SK_Scalar1) { |
| if (matrix.rectStaysRect() && SkScalarIsInt(matrix.getTranslateX()) && |
| SkScalarIsInt(matrix.getTranslateY())) { |
| *filterMode = GrTextureParams::kNone_FilterMode; |
| } else { |
| // Use bilerp to handle rotation or fractional translation. |
| *filterMode = GrTextureParams::kBilerp_FilterMode; |
| } |
| return false; |
| } |
| // When we use the bicubic filtering effect each sample is read from the texture using |
| // nearest neighbor sampling. |
| *filterMode = GrTextureParams::kNone_FilterMode; |
| return true; |
| } |