| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrConvolutionEffect_DEFINED |
| #define GrConvolutionEffect_DEFINED |
| |
| #include "Gr1DKernelEffect.h" |
| #include "GrInvariantOutput.h" |
| |
| /** |
| * A convolution effect. The kernel is specified as an array of 2 * half-width |
| * + 1 weights. Each texel is multiplied by it's weight and summed to determine |
| * the output color. The output color is modulated by the input color. |
| */ |
| class GrConvolutionEffect : public Gr1DKernelEffect { |
| |
| public: |
| |
| /// Convolve with an arbitrary user-specified kernel |
| static GrFragmentProcessor* Create(GrProcessorDataManager* procDataManager, |
| GrTexture* tex, |
| Direction dir, |
| int halfWidth, |
| const float* kernel, |
| bool useBounds, |
| float bounds[2]) { |
| return SkNEW_ARGS(GrConvolutionEffect, (procDataManager, |
| tex, |
| dir, |
| halfWidth, |
| kernel, |
| useBounds, |
| bounds)); |
| } |
| |
| /// Convolve with a Gaussian kernel |
| static GrFragmentProcessor* CreateGaussian(GrProcessorDataManager* procDataManager, |
| GrTexture* tex, |
| Direction dir, |
| int halfWidth, |
| float gaussianSigma, |
| bool useBounds, |
| float bounds[2]) { |
| return SkNEW_ARGS(GrConvolutionEffect, (procDataManager, |
| tex, |
| dir, |
| halfWidth, |
| gaussianSigma, |
| useBounds, |
| bounds)); |
| } |
| |
| virtual ~GrConvolutionEffect(); |
| |
| const float* kernel() const { return fKernel; } |
| |
| const float* bounds() const { return fBounds; } |
| bool useBounds() const { return fUseBounds; } |
| |
| const char* name() const override { return "Convolution"; } |
| |
| enum { |
| // This was decided based on the min allowed value for the max texture |
| // samples per fragment program run in DX9SM2 (32). A sigma param of 4.0 |
| // on a blur filter gives a kernel width of 25 while a sigma of 5.0 |
| // would exceed a 32 wide kernel. |
| kMaxKernelRadius = 12, |
| // With a C++11 we could have a constexpr version of WidthFromRadius() |
| // and not have to duplicate this calculation. |
| kMaxKernelWidth = 2 * kMaxKernelRadius + 1, |
| }; |
| |
| protected: |
| |
| float fKernel[kMaxKernelWidth]; |
| bool fUseBounds; |
| float fBounds[2]; |
| |
| private: |
| GrConvolutionEffect(GrProcessorDataManager*, |
| GrTexture*, Direction, |
| int halfWidth, |
| const float* kernel, |
| bool useBounds, |
| float bounds[2]); |
| |
| /// Convolve with a Gaussian kernel |
| GrConvolutionEffect(GrProcessorDataManager*, |
| GrTexture*, Direction, |
| int halfWidth, |
| float gaussianSigma, |
| bool useBounds, |
| float bounds[2]); |
| |
| GrGLFragmentProcessor* onCreateGLInstance() const override; |
| |
| void onGetGLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override; |
| |
| bool onIsEqual(const GrFragmentProcessor&) const override; |
| |
| void onComputeInvariantOutput(GrInvariantOutput* inout) const override { |
| // If the texture was opaque we could know that the output color if we knew the sum of the |
| // kernel values. |
| inout->mulByUnknownFourComponents(); |
| } |
| |
| GR_DECLARE_FRAGMENT_PROCESSOR_TEST; |
| |
| typedef Gr1DKernelEffect INHERITED; |
| }; |
| |
| #endif |