src/gpu/effects/GrConvolutionEffect.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "GrConvolutionEffect.h"
 #include "gl/GrGLEffect.h"
 #include "gl/GrGLSL.h"
 #include "gl/GrGLTexture.h"
 #include "GrTBackendEffectFactory.h"

 // For brevity
 typedef GrGLUniformManager::UniformHandle UniformHandle;

 class GrGLConvolutionEffect : public GrGLEffect {
 public:
     GrGLConvolutionEffect(const GrBackendEffectFactory&, const GrDrawEffect&);

     virtual void emitCode(GrGLShaderBuilder*,
                           const GrDrawEffect&,
                           EffectKey,
                           const char* outputColor,
                           const char* inputColor,
                           const TransformedCoordsArray&,
                           const TextureSamplerArray&) SK_OVERRIDE;

     virtual void setData(const GrGLUniformManager& uman, const GrDrawEffect&) SK_OVERRIDE;

     static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);

 private:
     int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); }
     bool useBounds() const { return fUseBounds; }
     Gr1DKernelEffect::Direction direction() const { return fDirection; }

     int                 fRadius;
     bool                fUseBounds;
     Gr1DKernelEffect::Direction    fDirection;
     UniformHandle       fKernelUni;
     UniformHandle       fImageIncrementUni;
     UniformHandle       fBoundsUni;

     typedef GrGLEffect INHERITED;
 };

 GrGLConvolutionEffect::GrGLConvolutionEffect(const GrBackendEffectFactory& factory,
                                              const GrDrawEffect& drawEffect)
     : INHERITED(factory) {
     const GrConvolutionEffect& c = drawEffect.castEffect<GrConvolutionEffect>();
     fRadius = c.radius();
     fUseBounds = c.useBounds();
     fDirection = c.direction();
 }

 void GrGLConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
                                      const GrDrawEffect&,
                                      EffectKey key,
                                      const char* outputColor,
                                      const char* inputColor,
                                      const TransformedCoordsArray& coords,
                                      const TextureSamplerArray& samplers) {
     SkString coords2D = builder->ensureFSCoords2D(coords, 0);
     fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                              kVec2f_GrSLType, "ImageIncrement");
     if (this->useBounds()) {
         fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                          kVec2f_GrSLType, "Bounds");
     }
     fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
                                           kFloat_GrSLType, "Kernel", this->width());

     builder->fsCodeAppendf("\t\t%s = vec4(0, 0, 0, 0);\n", outputColor);

     int width = this->width();
     const GrGLShaderVar& kernel = builder->getUniformVariable(fKernelUni);
     const char* imgInc = builder->getUniformCStr(fImageIncrementUni);

     builder->fsCodeAppendf("\t\tvec2 coord = %s - %d.0 * %s;\n", coords2D.c_str(), fRadius, imgInc);

     // Manually unroll loop because some drivers don't; yields 20-30% speedup.
     for (int i = 0; i < width; i++) {
         SkString index;
         SkString kernelIndex;
         index.appendS32(i);
         kernel.appendArrayAccess(index.c_str(), &kernelIndex);
         builder->fsCodeAppendf("\t\t%s += ", outputColor);
         builder->fsAppendTextureLookup(samplers[0], "coord");
         if (this->useBounds()) {
             const char* bounds = builder->getUniformCStr(fBoundsUni);
             const char* component = this->direction() == Gr1DKernelEffect::kY_Direction ? "y" : "x";
             builder->fsCodeAppendf(" * float(coord.%s >= %s.x && coord.%s <= %s.y)",
                 component, bounds, component, bounds);
         }
         builder->fsCodeAppendf(" * %s;\n", kernelIndex.c_str());
         builder->fsCodeAppendf("\t\tcoord += %s;\n", imgInc);
     }

     SkString modulate;
     GrGLSLMulVarBy4f(&modulate, 2, outputColor, inputColor);
     builder->fsCodeAppend(modulate.c_str());
 }

 void GrGLConvolutionEffect::setData(const GrGLUniformManager& uman,
                                     const GrDrawEffect& drawEffect) {
     const GrConvolutionEffect& conv = drawEffect.castEffect<GrConvolutionEffect>();
     GrTexture& texture = *conv.texture(0);
     // the code we generated was for a specific kernel radius
     SkASSERT(conv.radius() == fRadius);
     float imageIncrement[2] = { 0 };
     float ySign = texture.origin() != kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
     switch (conv.direction()) {
         case Gr1DKernelEffect::kX_Direction:
             imageIncrement[0] = 1.0f / texture.width();
             break;
         case Gr1DKernelEffect::kY_Direction:
             imageIncrement[1] = ySign / texture.height();
             break;
         default:
             SkFAIL("Unknown filter direction.");
     }
     uman.set2fv(fImageIncrementUni, 1, imageIncrement);
     if (conv.useBounds()) {
         const float* bounds = conv.bounds();
         if (Gr1DKernelEffect::kY_Direction == conv.direction() &&
             texture.origin() != kTopLeft_GrSurfaceOrigin) {
             uman.set2f(fBoundsUni, 1.0f - bounds[1], 1.0f - bounds[0]);
         } else {
             uman.set2f(fBoundsUni, bounds[0], bounds[1]);
         }
     }
     uman.set1fv(fKernelUni, this->width(), conv.kernel());
 }

 GrGLEffect::EffectKey GrGLConvolutionEffect::GenKey(const GrDrawEffect& drawEffect,
                                                     const GrGLCaps&) {
     const GrConvolutionEffect& conv = drawEffect.castEffect<GrConvolutionEffect>();
     EffectKey key = conv.radius();
     key <<= 2;
     if (conv.useBounds()) {
         key |= 0x2;
         key |= GrConvolutionEffect::kY_Direction == conv.direction() ? 0x1 : 0x0;
     }
     return key;
 }

 ///////////////////////////////////////////////////////////////////////////////

 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
                                          Direction direction,
                                          int radius,
                                          const float* kernel,
                                          bool useBounds,
                                          float bounds[2])
     : Gr1DKernelEffect(texture, direction, radius), fUseBounds(useBounds) {
     SkASSERT(radius <= kMaxKernelRadius);
     SkASSERT(NULL != kernel);
     int width = this->width();
     for (int i = 0; i < width; i++) {
         fKernel[i] = kernel[i];
     }
     memcpy(fBounds, bounds, sizeof(fBounds));
 }

 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
                                          Direction direction,
                                          int radius,
                                          float gaussianSigma,
                                          bool useBounds,
                                          float bounds[2])
     : Gr1DKernelEffect(texture, direction, radius), fUseBounds(useBounds) {
     SkASSERT(radius <= kMaxKernelRadius);
     int width = this->width();

     float sum = 0.0f;
     float denom = 1.0f / (2.0f * gaussianSigma * gaussianSigma);
     for (int i = 0; i < width; ++i) {
         float x = static_cast<float>(i - this->radius());
         // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian
         // is dropped here, since we renormalize the kernel below.
         fKernel[i] = sk_float_exp(- x * x * denom);
         sum += fKernel[i];
     }
     // Normalize the kernel
     float scale = 1.0f / sum;
     for (int i = 0; i < width; ++i) {
         fKernel[i] *= scale;
     }
     memcpy(fBounds, bounds, sizeof(fBounds));
 }

 GrConvolutionEffect::~GrConvolutionEffect() {
 }

 const GrBackendEffectFactory& GrConvolutionEffect::getFactory() const {
     return GrTBackendEffectFactory<GrConvolutionEffect>::getInstance();
 }

 bool GrConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
     const GrConvolutionEffect& s = CastEffect<GrConvolutionEffect>(sBase);
     return (this->texture(0) == s.texture(0) &&
             this->radius() == s.radius() &&
             this->direction() == s.direction() &&
             this->useBounds() == s.useBounds() &&
             0 == memcmp(fBounds, s.fBounds, sizeof(fBounds)) &&
             0 == memcmp(fKernel, s.fKernel, this->width() * sizeof(float)));
 }

 ///////////////////////////////////////////////////////////////////////////////

 GR_DEFINE_EFFECT_TEST(GrConvolutionEffect);

 GrEffectRef* GrConvolutionEffect::TestCreate(SkRandom* random,
                                              GrContext*,
                                              const GrDrawTargetCaps&,
                                              GrTexture* textures[]) {
     int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
                                       GrEffectUnitTest::kAlphaTextureIdx;
     Direction dir = random->nextBool() ? kX_Direction : kY_Direction;
     int radius = random->nextRangeU(1, kMaxKernelRadius);
     float kernel[kMaxKernelWidth];
     for (size_t i = 0; i < SK_ARRAY_COUNT(kernel); ++i) {
         kernel[i] = random->nextSScalar1();
     }
     float bounds[2];
     for (size_t i = 0; i < SK_ARRAY_COUNT(bounds); ++i) {
         bounds[i] = random->nextF();
     }

     bool useBounds = random->nextBool();
     return GrConvolutionEffect::Create(textures[texIdx],
                                        dir,
                                        radius,
                                        kernel,
                                        useBounds,
                                        bounds);
 }
	/*
	* Copyright 2012 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "GrConvolutionEffect.h"
	#include "gl/GrGLEffect.h"
	#include "gl/GrGLSL.h"
	#include "gl/GrGLTexture.h"
	#include "GrTBackendEffectFactory.h"

	// For brevity
	typedef GrGLUniformManager::UniformHandle UniformHandle;

	class GrGLConvolutionEffect : public GrGLEffect {
	public:
	GrGLConvolutionEffect(const GrBackendEffectFactory&, const GrDrawEffect&);

	virtual void emitCode(GrGLShaderBuilder*,
	const GrDrawEffect&,
	EffectKey,
	const char* outputColor,
	const char* inputColor,
	const TransformedCoordsArray&,
	const TextureSamplerArray&) SK_OVERRIDE;

	virtual void setData(const GrGLUniformManager& uman, const GrDrawEffect&) SK_OVERRIDE;

	static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);

	private:
	int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); }
	bool useBounds() const { return fUseBounds; }
	Gr1DKernelEffect::Direction direction() const { return fDirection; }

	int fRadius;
	bool fUseBounds;
	Gr1DKernelEffect::Direction fDirection;
	UniformHandle fKernelUni;
	UniformHandle fImageIncrementUni;
	UniformHandle fBoundsUni;

	typedef GrGLEffect INHERITED;
	};

	GrGLConvolutionEffect::GrGLConvolutionEffect(const GrBackendEffectFactory& factory,
	const GrDrawEffect& drawEffect)
	: INHERITED(factory) {
	const GrConvolutionEffect& c = drawEffect.castEffect<GrConvolutionEffect>();
	fRadius = c.radius();
	fUseBounds = c.useBounds();
	fDirection = c.direction();
	}

	void GrGLConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
	const GrDrawEffect&,
	EffectKey key,
	const char* outputColor,
	const char* inputColor,
	const TransformedCoordsArray& coords,
	const TextureSamplerArray& samplers) {
	SkString coords2D = builder->ensureFSCoords2D(coords, 0);
	fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
	kVec2f_GrSLType, "ImageIncrement");
	if (this->useBounds()) {
	fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
	kVec2f_GrSLType, "Bounds");
	}
	fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
	kFloat_GrSLType, "Kernel", this->width());

	builder->fsCodeAppendf("\t\t%s = vec4(0, 0, 0, 0);\n", outputColor);

	int width = this->width();
	const GrGLShaderVar& kernel = builder->getUniformVariable(fKernelUni);
	const char* imgInc = builder->getUniformCStr(fImageIncrementUni);

	builder->fsCodeAppendf("\t\tvec2 coord = %s - %d.0 * %s;\n", coords2D.c_str(), fRadius, imgInc);

	// Manually unroll loop because some drivers don't; yields 20-30% speedup.
	for (int i = 0; i < width; i++) {
	SkString index;
	SkString kernelIndex;
	index.appendS32(i);
	kernel.appendArrayAccess(index.c_str(), &kernelIndex);
	builder->fsCodeAppendf("\t\t%s += ", outputColor);
	builder->fsAppendTextureLookup(samplers[0], "coord");
	if (this->useBounds()) {
	const char* bounds = builder->getUniformCStr(fBoundsUni);
	const char* component = this->direction() == Gr1DKernelEffect::kY_Direction ? "y" : "x";
	builder->fsCodeAppendf(" * float(coord.%s >= %s.x && coord.%s <= %s.y)",
	component, bounds, component, bounds);
	}
	builder->fsCodeAppendf(" * %s;\n", kernelIndex.c_str());
	builder->fsCodeAppendf("\t\tcoord += %s;\n", imgInc);
	}

	SkString modulate;
	GrGLSLMulVarBy4f(&modulate, 2, outputColor, inputColor);
	builder->fsCodeAppend(modulate.c_str());
	}

	void GrGLConvolutionEffect::setData(const GrGLUniformManager& uman,
	const GrDrawEffect& drawEffect) {
	const GrConvolutionEffect& conv = drawEffect.castEffect<GrConvolutionEffect>();
	GrTexture& texture = *conv.texture(0);
	// the code we generated was for a specific kernel radius
	SkASSERT(conv.radius() == fRadius);
	float imageIncrement[2] = { 0 };
	float ySign = texture.origin() != kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
	switch (conv.direction()) {
	case Gr1DKernelEffect::kX_Direction:
	imageIncrement[0] = 1.0f / texture.width();
	break;
	case Gr1DKernelEffect::kY_Direction:
	imageIncrement[1] = ySign / texture.height();
	break;
	default:
	SkFAIL("Unknown filter direction.");
	}
	uman.set2fv(fImageIncrementUni, 1, imageIncrement);
	if (conv.useBounds()) {
	const float* bounds = conv.bounds();
	if (Gr1DKernelEffect::kY_Direction == conv.direction() &&
	texture.origin() != kTopLeft_GrSurfaceOrigin) {
	uman.set2f(fBoundsUni, 1.0f - bounds[1], 1.0f - bounds[0]);
	} else {
	uman.set2f(fBoundsUni, bounds[0], bounds[1]);
	}
	}
	uman.set1fv(fKernelUni, this->width(), conv.kernel());
	}

	GrGLEffect::EffectKey GrGLConvolutionEffect::GenKey(const GrDrawEffect& drawEffect,
	const GrGLCaps&) {
	const GrConvolutionEffect& conv = drawEffect.castEffect<GrConvolutionEffect>();
	EffectKey key = conv.radius();
	key <<= 2;
	if (conv.useBounds()) {
	key \|= 0x2;
	key \|= GrConvolutionEffect::kY_Direction == conv.direction() ? 0x1 : 0x0;
	}
	return key;
	}

	///////////////////////////////////////////////////////////////////////////////

	GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
	Direction direction,
	int radius,
	const float* kernel,
	bool useBounds,
	float bounds[2])
	: Gr1DKernelEffect(texture, direction, radius), fUseBounds(useBounds) {
	SkASSERT(radius <= kMaxKernelRadius);
	SkASSERT(NULL != kernel);
	int width = this->width();
	for (int i = 0; i < width; i++) {
	fKernel[i] = kernel[i];
	}
	memcpy(fBounds, bounds, sizeof(fBounds));
	}

	GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
	Direction direction,
	int radius,
	float gaussianSigma,
	bool useBounds,
	float bounds[2])
	: Gr1DKernelEffect(texture, direction, radius), fUseBounds(useBounds) {
	SkASSERT(radius <= kMaxKernelRadius);
	int width = this->width();

	float sum = 0.0f;
	float denom = 1.0f / (2.0f * gaussianSigma * gaussianSigma);
	for (int i = 0; i < width; ++i) {
	float x = static_cast<float>(i - this->radius());
	// Note that the constant term (1/(sqrt(2pisigma^2)) of the Gaussian
	// is dropped here, since we renormalize the kernel below.
	fKernel[i] = sk_float_exp(- x * x * denom);
	sum += fKernel[i];
	}
	// Normalize the kernel
	float scale = 1.0f / sum;
	for (int i = 0; i < width; ++i) {
	fKernel[i] *= scale;
	}
	memcpy(fBounds, bounds, sizeof(fBounds));
	}

	GrConvolutionEffect::~GrConvolutionEffect() {
	}

	const GrBackendEffectFactory& GrConvolutionEffect::getFactory() const {
	return GrTBackendEffectFactory<GrConvolutionEffect>::getInstance();
	}

	bool GrConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
	const GrConvolutionEffect& s = CastEffect<GrConvolutionEffect>(sBase);
	return (this->texture(0) == s.texture(0) &&
	this->radius() == s.radius() &&
	this->direction() == s.direction() &&
	this->useBounds() == s.useBounds() &&
	0 == memcmp(fBounds, s.fBounds, sizeof(fBounds)) &&
	0 == memcmp(fKernel, s.fKernel, this->width() * sizeof(float)));
	}

	///////////////////////////////////////////////////////////////////////////////

	GR_DEFINE_EFFECT_TEST(GrConvolutionEffect);

	GrEffectRef* GrConvolutionEffect::TestCreate(SkRandom* random,
	GrContext*,
	const GrDrawTargetCaps&,
	GrTexture* textures[]) {
	int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
	GrEffectUnitTest::kAlphaTextureIdx;
	Direction dir = random->nextBool() ? kX_Direction : kY_Direction;
	int radius = random->nextRangeU(1, kMaxKernelRadius);
	float kernel[kMaxKernelWidth];
	for (size_t i = 0; i < SK_ARRAY_COUNT(kernel); ++i) {
	kernel[i] = random->nextSScalar1();
	}
	float bounds[2];
	for (size_t i = 0; i < SK_ARRAY_COUNT(bounds); ++i) {
	bounds[i] = random->nextF();
	}

	bool useBounds = random->nextBool();
	return GrConvolutionEffect::Create(textures[texIdx],
	dir,
	radius,
	kernel,
	useBounds,
	bounds);
	}