libs/hwui/SkiaShader.cpp - platform/frameworks/base - Gitiles

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "OpenGLRenderer"

 #include <utils/Log.h>

 #include <SkMatrix.h>

 #include "SkiaShader.h"
 #include "Texture.h"
 #include "Matrix.h"

 namespace android {
 namespace uirenderer {

 ///////////////////////////////////////////////////////////////////////////////
 // Support
 ///////////////////////////////////////////////////////////////////////////////

 static const GLenum gTextureUnitsMap[] = {
         GL_TEXTURE0,
         GL_TEXTURE1,
         GL_TEXTURE2
 };

 static const GLint gTileModes[] = {
         GL_CLAMP_TO_EDGE,   // == SkShader::kClamp_TileMode
         GL_REPEAT,          // == SkShader::kRepeat_Mode
         GL_MIRRORED_REPEAT  // == SkShader::kMirror_TileMode
 };

 ///////////////////////////////////////////////////////////////////////////////
 // Base shader
 ///////////////////////////////////////////////////////////////////////////////

 SkiaShader::SkiaShader(Type type, SkShader* key, SkShader::TileMode tileX,
         SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
         mType(type), mKey(key), mTileX(tileX), mTileY(tileY), mBlend(blend) {
     setMatrix(matrix);
 }

 SkiaShader::~SkiaShader() {
 }

 void SkiaShader::describe(ProgramDescription& description, const Extensions& extensions) {
 }

 void SkiaShader::setupProgram(Program* program, const mat4& modelView, const Snapshot& snapshot,
         GLuint* textureUnit) {
 }

 void SkiaShader::bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit) {
     glActiveTexture(gTextureUnitsMap[textureUnit]);
     glBindTexture(GL_TEXTURE_2D, texture);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
 }

 void SkiaShader::computeScreenSpaceMatrix(mat4& screenSpace, const mat4& modelView) {
     screenSpace.loadMultiply(mUnitMatrix, mShaderMatrix);
     screenSpace.multiply(modelView);
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Bitmap shader
 ///////////////////////////////////////////////////////////////////////////////

 SkiaBitmapShader::SkiaBitmapShader(SkBitmap* bitmap, SkShader* key, SkShader::TileMode tileX,
         SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
         SkiaShader(kBitmap, key, tileX, tileY, matrix, blend), mBitmap(bitmap), mTexture(NULL) {
     updateLocalMatrix(matrix);
 }

 void SkiaBitmapShader::describe(ProgramDescription& description, const Extensions& extensions) {
     const Texture* texture = mTextureCache->get(mBitmap);
     if (!texture) return;
     mTexture = texture;

     const float width = texture->width;
     const float height = texture->height;

     description.hasBitmap = true;
     // The driver does not support non-power of two mirrored/repeated
     // textures, so do it ourselves
     if (!extensions.hasNPot() && (!isPowerOfTwo(width) || !isPowerOfTwo(height)) &&
             (mTileX != SkShader::kClamp_TileMode || mTileY != SkShader::kClamp_TileMode)) {
         description.isBitmapNpot = true;
         description.bitmapWrapS = gTileModes[mTileX];
         description.bitmapWrapT = gTileModes[mTileY];
         mWrapS = GL_CLAMP_TO_EDGE;
         mWrapT = GL_CLAMP_TO_EDGE;
     } else {
         mWrapS = gTileModes[mTileX];
         mWrapT = gTileModes[mTileY];
     }
 }

 void SkiaBitmapShader::setupProgram(Program* program, const mat4& modelView,
         const Snapshot& snapshot, GLuint* textureUnit) {
     GLuint textureSlot = (*textureUnit)++;
     glActiveTexture(gTextureUnitsMap[textureSlot]);

     const Texture* texture = mTexture;
     mTexture = NULL;
     if (!texture) return;
     const AutoTexture autoCleanup(texture);

     const float width = texture->width;
     const float height = texture->height;

     mat4 textureTransform;
     computeScreenSpaceMatrix(textureTransform, modelView);

     // Uniforms
     bindTexture(texture->id, mWrapS, mWrapT, textureSlot);
     glUniform1i(program->getUniform("bitmapSampler"), textureSlot);
     glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
             GL_FALSE, &textureTransform.data[0]);
     glUniform2f(program->getUniform("textureDimension"), 1.0f / width, 1.0f / height);
 }

 void SkiaBitmapShader::updateTransforms(Program* program, const mat4& modelView,
         const Snapshot& snapshot) {
     mat4 textureTransform;
     computeScreenSpaceMatrix(textureTransform, modelView);
     glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
             GL_FALSE, &textureTransform.data[0]);
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Linear gradient shader
 ///////////////////////////////////////////////////////////////////////////////

 static void toUnitMatrix(const SkPoint pts[2], SkMatrix* matrix) {
     SkVector vec = pts[1] - pts[0];
     const float mag = vec.length();
     const float inv = mag ? 1.0f / mag : 0;

     vec.scale(inv);
     matrix->setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
     matrix->postTranslate(-pts[0].fX, -pts[0].fY);
     matrix->postScale(inv, inv);
 }

 SkiaLinearGradientShader::SkiaLinearGradientShader(float* bounds, uint32_t* colors,
         float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
         SkMatrix* matrix, bool blend):
         SkiaShader(kLinearGradient, key, tileMode, tileMode, matrix, blend),
         mBounds(bounds), mColors(colors), mPositions(positions), mCount(count) {
     SkPoint points[2];
     points[0].set(bounds[0], bounds[1]);
     points[1].set(bounds[2], bounds[3]);

     SkMatrix unitMatrix;
     toUnitMatrix(points, &unitMatrix);
     mUnitMatrix.load(unitMatrix);

     updateLocalMatrix(matrix);
 }

 SkiaLinearGradientShader::~SkiaLinearGradientShader() {
     delete[] mBounds;
     delete[] mColors;
     delete[] mPositions;
 }

 void SkiaLinearGradientShader::describe(ProgramDescription& description,
         const Extensions& extensions) {
     description.hasGradient = true;
     description.gradientType = ProgramDescription::kGradientLinear;
 }

 void SkiaLinearGradientShader::setupProgram(Program* program, const mat4& modelView,
         const Snapshot& snapshot, GLuint* textureUnit) {
     GLuint textureSlot = (*textureUnit)++;
     glActiveTexture(gTextureUnitsMap[textureSlot]);

     Texture* texture = mGradientCache->get(mKey);
     if (!texture) {
         texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount, mTileX);
     }

     mat4 screenSpace;
     computeScreenSpaceMatrix(screenSpace, modelView);

     // Uniforms
     bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
     glUniform1i(program->getUniform("gradientSampler"), textureSlot);
     glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
 }

 void SkiaLinearGradientShader::updateTransforms(Program* program, const mat4& modelView,
         const Snapshot& snapshot) {
     mat4 screenSpace;
     computeScreenSpaceMatrix(screenSpace, modelView);
     glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Circular gradient shader
 ///////////////////////////////////////////////////////////////////////////////

 static void toCircularUnitMatrix(const float x, const float y, const float radius,
         SkMatrix* matrix) {
     const float inv = 1.0f / radius;
     matrix->setTranslate(-x, -y);
     matrix->postScale(inv, inv);
 }

 SkiaCircularGradientShader::SkiaCircularGradientShader(float x, float y, float radius,
         uint32_t* colors, float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
         SkMatrix* matrix, bool blend):
         SkiaSweepGradientShader(kCircularGradient, x, y, colors, positions, count, key,
                 tileMode, matrix, blend) {
     SkMatrix unitMatrix;
     toCircularUnitMatrix(x, y, radius, &unitMatrix);
     mUnitMatrix.load(unitMatrix);

     updateLocalMatrix(matrix);
 }

 void SkiaCircularGradientShader::describe(ProgramDescription& description,
         const Extensions& extensions) {
     description.hasGradient = true;
     description.gradientType = ProgramDescription::kGradientCircular;
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Sweep gradient shader
 ///////////////////////////////////////////////////////////////////////////////

 static void toSweepUnitMatrix(const float x, const float y, SkMatrix* matrix) {
     matrix->setTranslate(-x, -y);
 }

 SkiaSweepGradientShader::SkiaSweepGradientShader(float x, float y, uint32_t* colors,
         float* positions, int count, SkShader* key, SkMatrix* matrix, bool blend):
         SkiaShader(kSweepGradient, key, SkShader::kClamp_TileMode,
                 SkShader::kClamp_TileMode, matrix, blend),
         mColors(colors), mPositions(positions), mCount(count) {
     SkMatrix unitMatrix;
     toSweepUnitMatrix(x, y, &unitMatrix);
     mUnitMatrix.load(unitMatrix);

     updateLocalMatrix(matrix);
 }

 SkiaSweepGradientShader::SkiaSweepGradientShader(Type type, float x, float y, uint32_t* colors,
         float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
         SkMatrix* matrix, bool blend):
         SkiaShader(type, key, tileMode, tileMode, matrix, blend),
         mColors(colors), mPositions(positions), mCount(count) {
 }

 SkiaSweepGradientShader::~SkiaSweepGradientShader() {
     delete[] mColors;
     delete[] mPositions;
 }

 void SkiaSweepGradientShader::describe(ProgramDescription& description,
         const Extensions& extensions) {
     description.hasGradient = true;
     description.gradientType = ProgramDescription::kGradientSweep;
 }

 void SkiaSweepGradientShader::setupProgram(Program* program, const mat4& modelView,
         const Snapshot& snapshot, GLuint* textureUnit) {
     GLuint textureSlot = (*textureUnit)++;
     glActiveTexture(gTextureUnitsMap[textureSlot]);

     Texture* texture = mGradientCache->get(mKey);
     if (!texture) {
         texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount);
     }

     mat4 screenSpace;
     computeScreenSpaceMatrix(screenSpace, modelView);

     // Uniforms
     bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
     glUniform1i(program->getUniform("gradientSampler"), textureSlot);
     glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
 }

 void SkiaSweepGradientShader::updateTransforms(Program* program, const mat4& modelView,
         const Snapshot& snapshot) {
     mat4 screenSpace;
     computeScreenSpaceMatrix(screenSpace, modelView);
     glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Compose shader
 ///////////////////////////////////////////////////////////////////////////////

 SkiaComposeShader::SkiaComposeShader(SkiaShader* first, SkiaShader* second,
         SkXfermode::Mode mode, SkShader* key):
         SkiaShader(kCompose, key, SkShader::kClamp_TileMode, SkShader::kClamp_TileMode,
         NULL, first->blend() || second->blend()), mFirst(first), mSecond(second), mMode(mode) {
 }

 void SkiaComposeShader::set(TextureCache* textureCache, GradientCache* gradientCache) {
     SkiaShader::set(textureCache, gradientCache);
     mFirst->set(textureCache, gradientCache);
     mSecond->set(textureCache, gradientCache);
 }

 void SkiaComposeShader::describe(ProgramDescription& description, const Extensions& extensions) {
     mFirst->describe(description, extensions);
     mSecond->describe(description, extensions);
     if (mFirst->type() == kBitmap) {
         description.isBitmapFirst = true;
     }
     description.shadersMode = mMode;
 }

 void SkiaComposeShader::setupProgram(Program* program, const mat4& modelView,
         const Snapshot& snapshot, GLuint* textureUnit) {
     mFirst->setupProgram(program, modelView, snapshot, textureUnit);
     mSecond->setupProgram(program, modelView, snapshot, textureUnit);
 }

 }; // namespace uirenderer
 }; // namespace android
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "OpenGLRenderer"

	#include <utils/Log.h>

	#include <SkMatrix.h>

	#include "SkiaShader.h"
	#include "Texture.h"
	#include "Matrix.h"

	namespace android {
	namespace uirenderer {

	///////////////////////////////////////////////////////////////////////////////
	// Support
	///////////////////////////////////////////////////////////////////////////////

	static const GLenum gTextureUnitsMap[] = {
	GL_TEXTURE0,
	GL_TEXTURE1,
	GL_TEXTURE2
	};

	static const GLint gTileModes[] = {
	GL_CLAMP_TO_EDGE, // == SkShader::kClamp_TileMode
	GL_REPEAT, // == SkShader::kRepeat_Mode
	GL_MIRRORED_REPEAT // == SkShader::kMirror_TileMode
	};

	///////////////////////////////////////////////////////////////////////////////
	// Base shader
	///////////////////////////////////////////////////////////////////////////////

	SkiaShader::SkiaShader(Type type, SkShader* key, SkShader::TileMode tileX,
	SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
	mType(type), mKey(key), mTileX(tileX), mTileY(tileY), mBlend(blend) {
	setMatrix(matrix);
	}

	SkiaShader::~SkiaShader() {
	}

	void SkiaShader::describe(ProgramDescription& description, const Extensions& extensions) {
	}

	void SkiaShader::setupProgram(Program* program, const mat4& modelView, const Snapshot& snapshot,
	GLuint* textureUnit) {
	}

	void SkiaShader::bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit) {
	glActiveTexture(gTextureUnitsMap[textureUnit]);
	glBindTexture(GL_TEXTURE_2D, texture);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
	}

	void SkiaShader::computeScreenSpaceMatrix(mat4& screenSpace, const mat4& modelView) {
	screenSpace.loadMultiply(mUnitMatrix, mShaderMatrix);
	screenSpace.multiply(modelView);
	}

	///////////////////////////////////////////////////////////////////////////////
	// Bitmap shader
	///////////////////////////////////////////////////////////////////////////////

	SkiaBitmapShader::SkiaBitmapShader(SkBitmap* bitmap, SkShader* key, SkShader::TileMode tileX,
	SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
	SkiaShader(kBitmap, key, tileX, tileY, matrix, blend), mBitmap(bitmap), mTexture(NULL) {
	updateLocalMatrix(matrix);
	}

	void SkiaBitmapShader::describe(ProgramDescription& description, const Extensions& extensions) {
	const Texture* texture = mTextureCache->get(mBitmap);
	if (!texture) return;
	mTexture = texture;

	const float width = texture->width;
	const float height = texture->height;

	description.hasBitmap = true;
	// The driver does not support non-power of two mirrored/repeated
	// textures, so do it ourselves
	if (!extensions.hasNPot() && (!isPowerOfTwo(width) \|\| !isPowerOfTwo(height)) &&
	(mTileX != SkShader::kClamp_TileMode \|\| mTileY != SkShader::kClamp_TileMode)) {
	description.isBitmapNpot = true;
	description.bitmapWrapS = gTileModes[mTileX];
	description.bitmapWrapT = gTileModes[mTileY];
	mWrapS = GL_CLAMP_TO_EDGE;
	mWrapT = GL_CLAMP_TO_EDGE;
	} else {
	mWrapS = gTileModes[mTileX];
	mWrapT = gTileModes[mTileY];
	}
	}

	void SkiaBitmapShader::setupProgram(Program* program, const mat4& modelView,
	const Snapshot& snapshot, GLuint* textureUnit) {
	GLuint textureSlot = (*textureUnit)++;
	glActiveTexture(gTextureUnitsMap[textureSlot]);

	const Texture* texture = mTexture;
	mTexture = NULL;
	if (!texture) return;
	const AutoTexture autoCleanup(texture);

	const float width = texture->width;
	const float height = texture->height;

	mat4 textureTransform;
	computeScreenSpaceMatrix(textureTransform, modelView);

	// Uniforms
	bindTexture(texture->id, mWrapS, mWrapT, textureSlot);
	glUniform1i(program->getUniform("bitmapSampler"), textureSlot);
	glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
	GL_FALSE, &textureTransform.data[0]);
	glUniform2f(program->getUniform("textureDimension"), 1.0f / width, 1.0f / height);
	}

	void SkiaBitmapShader::updateTransforms(Program* program, const mat4& modelView,
	const Snapshot& snapshot) {
	mat4 textureTransform;
	computeScreenSpaceMatrix(textureTransform, modelView);
	glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
	GL_FALSE, &textureTransform.data[0]);
	}

	///////////////////////////////////////////////////////////////////////////////
	// Linear gradient shader
	///////////////////////////////////////////////////////////////////////////////

	static void toUnitMatrix(const SkPoint pts[2], SkMatrix* matrix) {
	SkVector vec = pts[1] - pts[0];
	const float mag = vec.length();
	const float inv = mag ? 1.0f / mag : 0;

	vec.scale(inv);
	matrix->setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
	matrix->postTranslate(-pts[0].fX, -pts[0].fY);
	matrix->postScale(inv, inv);
	}

	SkiaLinearGradientShader::SkiaLinearGradientShader(float* bounds, uint32_t* colors,
	float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
	SkMatrix* matrix, bool blend):
	SkiaShader(kLinearGradient, key, tileMode, tileMode, matrix, blend),
	mBounds(bounds), mColors(colors), mPositions(positions), mCount(count) {
	SkPoint points[2];
	points[0].set(bounds[0], bounds[1]);
	points[1].set(bounds[2], bounds[3]);

	SkMatrix unitMatrix;
	toUnitMatrix(points, &unitMatrix);
	mUnitMatrix.load(unitMatrix);

	updateLocalMatrix(matrix);
	}

	SkiaLinearGradientShader::~SkiaLinearGradientShader() {
	delete[] mBounds;
	delete[] mColors;
	delete[] mPositions;
	}

	void SkiaLinearGradientShader::describe(ProgramDescription& description,
	const Extensions& extensions) {
	description.hasGradient = true;
	description.gradientType = ProgramDescription::kGradientLinear;
	}

	void SkiaLinearGradientShader::setupProgram(Program* program, const mat4& modelView,
	const Snapshot& snapshot, GLuint* textureUnit) {
	GLuint textureSlot = (*textureUnit)++;
	glActiveTexture(gTextureUnitsMap[textureSlot]);

	Texture* texture = mGradientCache->get(mKey);
	if (!texture) {
	texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount, mTileX);
	}

	mat4 screenSpace;
	computeScreenSpaceMatrix(screenSpace, modelView);

	// Uniforms
	bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
	glUniform1i(program->getUniform("gradientSampler"), textureSlot);
	glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
	}

	void SkiaLinearGradientShader::updateTransforms(Program* program, const mat4& modelView,
	const Snapshot& snapshot) {
	mat4 screenSpace;
	computeScreenSpaceMatrix(screenSpace, modelView);
	glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
	}

	///////////////////////////////////////////////////////////////////////////////
	// Circular gradient shader
	///////////////////////////////////////////////////////////////////////////////

	static void toCircularUnitMatrix(const float x, const float y, const float radius,
	SkMatrix* matrix) {
	const float inv = 1.0f / radius;
	matrix->setTranslate(-x, -y);
	matrix->postScale(inv, inv);
	}

	SkiaCircularGradientShader::SkiaCircularGradientShader(float x, float y, float radius,
	uint32_t* colors, float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
	SkMatrix* matrix, bool blend):
	SkiaSweepGradientShader(kCircularGradient, x, y, colors, positions, count, key,
	tileMode, matrix, blend) {
	SkMatrix unitMatrix;
	toCircularUnitMatrix(x, y, radius, &unitMatrix);
	mUnitMatrix.load(unitMatrix);

	updateLocalMatrix(matrix);
	}

	void SkiaCircularGradientShader::describe(ProgramDescription& description,
	const Extensions& extensions) {
	description.hasGradient = true;
	description.gradientType = ProgramDescription::kGradientCircular;
	}

	///////////////////////////////////////////////////////////////////////////////
	// Sweep gradient shader
	///////////////////////////////////////////////////////////////////////////////

	static void toSweepUnitMatrix(const float x, const float y, SkMatrix* matrix) {
	matrix->setTranslate(-x, -y);
	}

	SkiaSweepGradientShader::SkiaSweepGradientShader(float x, float y, uint32_t* colors,
	float* positions, int count, SkShader* key, SkMatrix* matrix, bool blend):
	SkiaShader(kSweepGradient, key, SkShader::kClamp_TileMode,
	SkShader::kClamp_TileMode, matrix, blend),
	mColors(colors), mPositions(positions), mCount(count) {
	SkMatrix unitMatrix;
	toSweepUnitMatrix(x, y, &unitMatrix);
	mUnitMatrix.load(unitMatrix);

	updateLocalMatrix(matrix);
	}

	SkiaSweepGradientShader::SkiaSweepGradientShader(Type type, float x, float y, uint32_t* colors,
	float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
	SkMatrix* matrix, bool blend):
	SkiaShader(type, key, tileMode, tileMode, matrix, blend),
	mColors(colors), mPositions(positions), mCount(count) {
	}

	SkiaSweepGradientShader::~SkiaSweepGradientShader() {
	delete[] mColors;
	delete[] mPositions;
	}

	void SkiaSweepGradientShader::describe(ProgramDescription& description,
	const Extensions& extensions) {
	description.hasGradient = true;
	description.gradientType = ProgramDescription::kGradientSweep;
	}

	void SkiaSweepGradientShader::setupProgram(Program* program, const mat4& modelView,
	const Snapshot& snapshot, GLuint* textureUnit) {
	GLuint textureSlot = (*textureUnit)++;
	glActiveTexture(gTextureUnitsMap[textureSlot]);

	Texture* texture = mGradientCache->get(mKey);
	if (!texture) {
	texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount);
	}

	mat4 screenSpace;
	computeScreenSpaceMatrix(screenSpace, modelView);

	// Uniforms
	bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
	glUniform1i(program->getUniform("gradientSampler"), textureSlot);
	glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
	}

	void SkiaSweepGradientShader::updateTransforms(Program* program, const mat4& modelView,
	const Snapshot& snapshot) {
	mat4 screenSpace;
	computeScreenSpaceMatrix(screenSpace, modelView);
	glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
	}

	///////////////////////////////////////////////////////////////////////////////
	// Compose shader
	///////////////////////////////////////////////////////////////////////////////

	SkiaComposeShader::SkiaComposeShader(SkiaShader* first, SkiaShader* second,
	SkXfermode::Mode mode, SkShader* key):
	SkiaShader(kCompose, key, SkShader::kClamp_TileMode, SkShader::kClamp_TileMode,
	NULL, first->blend() \|\| second->blend()), mFirst(first), mSecond(second), mMode(mode) {
	}

	void SkiaComposeShader::set(TextureCache* textureCache, GradientCache* gradientCache) {
	SkiaShader::set(textureCache, gradientCache);
	mFirst->set(textureCache, gradientCache);
	mSecond->set(textureCache, gradientCache);
	}

	void SkiaComposeShader::describe(ProgramDescription& description, const Extensions& extensions) {
	mFirst->describe(description, extensions);
	mSecond->describe(description, extensions);
	if (mFirst->type() == kBitmap) {
	description.isBitmapFirst = true;
	}
	description.shadersMode = mMode;
	}

	void SkiaComposeShader::setupProgram(Program* program, const mat4& modelView,
	const Snapshot& snapshot, GLuint* textureUnit) {
	mFirst->setupProgram(program, modelView, snapshot, textureUnit);
	mSecond->setupProgram(program, modelView, snapshot, textureUnit);
	}

	}; // namespace uirenderer
	}; // namespace android