blob: be29af077f0a10a4e4a465f9537552147de032cf [file] [log] [blame]
/*
* Copyright 2022 Google LLC
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkColorFilter.h"
#include "include/core/SkFlattenable.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkTypes.h"
#include "src/core/SkColorFilterBase.h"
#include "src/core/SkColorFilterPriv.h"
#include "src/core/SkEffectPriv.h"
#include "src/core/SkRasterPipeline.h"
#include "src/core/SkRasterPipelineOpList.h"
#include "src/core/SkVM.h"
#if SK_SUPPORT_GPU
#include "src/gpu/ganesh/GrFragmentProcessor.h"
#include <memory>
#include <utility>
class GrColorInfo;
class GrRecordingContext;
class SkSurfaceProps;
#endif
class SkArenaAlloc;
class SkColorInfo;
class SkReadBuffer;
class SkWriteBuffer;
#ifdef SK_GRAPHITE_ENABLED
#include "src/gpu/graphite/KeyContext.h"
#include "src/gpu/graphite/KeyHelpers.h"
#include "src/gpu/graphite/PaintParamsKey.h"
namespace skgpu::graphite {
class PipelineDataGatherer;
}
#endif
/**
* Remaps the input color's alpha to a Gaussian ramp and then outputs premul white using the
* remapped alpha.
*/
class SkGaussianColorFilter final : public SkColorFilterBase {
public:
SkGaussianColorFilter() : SkColorFilterBase() {}
bool appendStages(const SkStageRec& rec, bool shaderIsOpaque) const override {
rec.fPipeline->append(SkRasterPipelineOp::gauss_a_to_rgba);
return true;
}
#if SK_SUPPORT_GPU
GrFPResult asFragmentProcessor(std::unique_ptr<GrFragmentProcessor> inputFP,
GrRecordingContext*,
const GrColorInfo&,
const SkSurfaceProps&) const override;
#endif
#ifdef SK_GRAPHITE_ENABLED
void addToKey(const skgpu::graphite::KeyContext&,
skgpu::graphite::PaintParamsKeyBuilder*,
skgpu::graphite::PipelineDataGatherer*) const override;
#endif
protected:
void flatten(SkWriteBuffer&) const override {}
skvm::Color onProgram(skvm::Builder* p, skvm::Color c, const SkColorInfo& dst, skvm::Uniforms*,
SkArenaAlloc*) const override {
// x = 1 - x;
// exp(-x * x * 4) - 0.018f;
// ... now approximate with quartic
//
skvm::F32 x = p->splat(-2.26661229133605957031f);
x = c.a * x + 2.89795351028442382812f;
x = c.a * x + 0.21345567703247070312f;
x = c.a * x + 0.15489584207534790039f;
x = c.a * x + 0.00030726194381713867f;
return {x, x, x, x};
}
private:
SK_FLATTENABLE_HOOKS(SkGaussianColorFilter)
};
sk_sp<SkFlattenable> SkGaussianColorFilter::CreateProc(SkReadBuffer&) {
return SkColorFilterPriv::MakeGaussian();
}
#if SK_SUPPORT_GPU
#include "include/effects/SkRuntimeEffect.h"
#include "src/core/SkRuntimeEffectPriv.h"
#include "src/gpu/ganesh/effects/GrSkSLFP.h"
GrFPResult SkGaussianColorFilter::asFragmentProcessor(std::unique_ptr<GrFragmentProcessor> inputFP,
GrRecordingContext*,
const GrColorInfo&,
const SkSurfaceProps&) const {
static const SkRuntimeEffect* effect = SkMakeRuntimeEffect(SkRuntimeEffect::MakeForColorFilter,
"half4 main(half4 inColor) {"
"half factor = 1 - inColor.a;"
"factor = exp(-factor * factor * 4) - 0.018;"
"return half4(factor);"
"}"
);
SkASSERT(SkRuntimeEffectPriv::SupportsConstantOutputForConstantInput(effect));
return GrFPSuccess(GrSkSLFP::Make(effect, "gaussian_fp", std::move(inputFP),
GrSkSLFP::OptFlags::kNone));
}
#endif
#ifdef SK_GRAPHITE_ENABLED
void SkGaussianColorFilter::addToKey(const skgpu::graphite::KeyContext& keyContext,
skgpu::graphite::PaintParamsKeyBuilder* builder,
skgpu::graphite::PipelineDataGatherer* gatherer) const {
using namespace skgpu::graphite;
GaussianColorFilterBlock::BeginBlock(keyContext, builder, gatherer);
builder->endBlock();
}
#endif
sk_sp<SkColorFilter> SkColorFilterPriv::MakeGaussian() {
return sk_sp<SkColorFilter>(new SkGaussianColorFilter);
}