libs/hwui/LayerRenderer.cpp - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2011 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 <ui/Rect.h>

 #include "LayerCache.h"
 #include "LayerRenderer.h"
 #include "Matrix.h"
 #include "Properties.h"
 #include "Rect.h"

 namespace android {
 namespace uirenderer {

 ///////////////////////////////////////////////////////////////////////////////
 // Rendering
 ///////////////////////////////////////////////////////////////////////////////

 void LayerRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
     LAYER_RENDERER_LOGD("Rendering into layer, fbo = %d", mLayer->fbo);

     glBindFramebuffer(GL_FRAMEBUFFER, mLayer->fbo);

     const float width = mLayer->layer.getWidth();
     const float height = mLayer->layer.getHeight();

 #if RENDER_LAYERS_AS_REGIONS
     Rect dirty(left, top, right, bottom);
     if (dirty.isEmpty() || (dirty.left <= 0 && dirty.top <= 0 &&
             dirty.right >= width && dirty.bottom >= height)) {
         mLayer->region.clear();
         dirty.set(0.0f, 0.0f, width, height);
     } else {
         dirty.intersect(0.0f, 0.0f, width, height);
         android::Rect r(dirty.left, dirty.top, dirty.right, dirty.bottom);
         mLayer->region.subtractSelf(r);
     }

     OpenGLRenderer::prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, opaque);
 #else
     OpenGLRenderer::prepareDirty(0.0f, 0.0f, width, height, opaque);
 #endif
 }

 void LayerRenderer::finish() {
     OpenGLRenderer::finish();

     generateMesh();

     LAYER_RENDERER_LOGD("Finished rendering into layer, fbo = %d", mLayer->fbo);

     // No need to unbind our FBO, this will be taken care of by the caller
     // who will invoke OpenGLRenderer::resume()
 }

 GLint LayerRenderer::getTargetFbo() {
     return mLayer->fbo;
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Dirty region tracking
 ///////////////////////////////////////////////////////////////////////////////

 bool LayerRenderer::hasLayer() {
     return true;
 }

 Region* LayerRenderer::getRegion() {
 #if RENDER_LAYERS_AS_REGIONS
     if (getSnapshot()->flags & Snapshot::kFlagFboTarget) {
         return OpenGLRenderer::getRegion();
     }
     return &mLayer->region;
 #else
     return OpenGLRenderer::getRegion();
 #endif
 }

 void LayerRenderer::generateMesh() {
 #if RENDER_LAYERS_AS_REGIONS
     if (mLayer->region.isRect() || mLayer->region.isEmpty()) {
         if (mLayer->mesh) {
             delete mLayer->mesh;
             delete mLayer->meshIndices;

             mLayer->mesh = NULL;
             mLayer->meshIndices = NULL;
             mLayer->meshElementCount = 0;
         }

         mLayer->setRegionAsRect();
         return;
     }

     size_t count;
     const android::Rect* rects = mLayer->region.getArray(&count);

     GLsizei elementCount = count * 6;

     if (mLayer->mesh && mLayer->meshElementCount < elementCount) {
         delete mLayer->mesh;
         delete mLayer->meshIndices;

         mLayer->mesh = NULL;
         mLayer->meshIndices = NULL;
     }

     bool rebuildIndices = false;
     if (!mLayer->mesh) {
         mLayer->mesh = new TextureVertex[count * 4];
         mLayer->meshIndices = new uint16_t[elementCount];
         rebuildIndices = true;
     }
     mLayer->meshElementCount = elementCount;

     const float texX = 1.0f / float(mLayer->width);
     const float texY = 1.0f / float(mLayer->height);
     const float height = mLayer->layer.getHeight();

     TextureVertex* mesh = mLayer->mesh;
     uint16_t* indices = mLayer->meshIndices;

     for (size_t i = 0; i < count; i++) {
         const android::Rect* r = &rects[i];

         const float u1 = r->left * texX;
         const float v1 = (height - r->top) * texY;
         const float u2 = r->right * texX;
         const float v2 = (height - r->bottom) * texY;

         TextureVertex::set(mesh++, r->left, r->top, u1, v1);
         TextureVertex::set(mesh++, r->right, r->top, u2, v1);
         TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
         TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);

         if (rebuildIndices) {
             uint16_t quad = i * 4;
             int index = i * 6;
             indices[index    ] = quad;       // top-left
             indices[index + 1] = quad + 1;   // top-right
             indices[index + 2] = quad + 2;   // bottom-left
             indices[index + 3] = quad + 2;   // bottom-left
             indices[index + 4] = quad + 1;   // top-right
             indices[index + 5] = quad + 3;   // bottom-right
         }
     }
 #endif
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Layers management
 ///////////////////////////////////////////////////////////////////////////////

 Layer* LayerRenderer::createLayer(uint32_t width, uint32_t height, bool isOpaque) {
     LAYER_RENDERER_LOGD("Creating new layer %dx%d", width, height);

     GLuint fbo = Caches::getInstance().fboCache.get();
     if (!fbo) {
         LOGW("Could not obtain an FBO");
         return NULL;
     }

     glActiveTexture(GL_TEXTURE0);
     Layer* layer = Caches::getInstance().layerCache.get(width, height);
     if (!layer) {
         LOGW("Could not obtain a layer");
         return NULL;
     }

     layer->fbo = fbo;
     layer->layer.set(0.0f, 0.0f, width, height);
     layer->texCoords.set(0.0f, height / float(layer->height),
             width / float(layer->width), 0.0f);
     layer->alpha = 255;
     layer->mode = SkXfermode::kSrcOver_Mode;
     layer->blend = !isOpaque;
     layer->colorFilter = NULL;
     layer->region.clear();

     GLuint previousFbo;
     glGetIntegerv(GL_FRAMEBUFFER_BINDING, (GLint*) &previousFbo);

     glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
     glBindTexture(GL_TEXTURE_2D, layer->texture);

     // Initialize the texture if needed
     if (layer->empty) {
         layer->empty = false;
         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
                 GL_RGBA, GL_UNSIGNED_BYTE, NULL);

         if (glGetError() != GL_NO_ERROR) {
             LOGD("Could not allocate texture");
             glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
             glDeleteTextures(1, &layer->texture);
             Caches::getInstance().fboCache.put(fbo);
             delete layer;
             return NULL;
         }
     }

     glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
             layer->texture, 0);

     glDisable(GL_SCISSOR_TEST);
     glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
     glClear(GL_COLOR_BUFFER_BIT);
     glEnable(GL_SCISSOR_TEST);

     glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);

     return layer;
 }

 bool LayerRenderer::resizeLayer(Layer* layer, uint32_t width, uint32_t height) {
     if (layer) {
         LAYER_RENDERER_LOGD("Resizing layer fbo = %d to %dx%d", layer->fbo, width, height);

         if (Caches::getInstance().layerCache.resize(layer, width, height)) {
             layer->layer.set(0.0f, 0.0f, width, height);
             layer->texCoords.set(0.0f, height / float(layer->height),
                     width / float(layer->width), 0.0f);
         } else {
             if (layer->texture) glDeleteTextures(1, &layer->texture);
             delete layer;
             return false;
         }
     }

     return true;
 }

 static void setTextureParameters(Layer* layer) {
     glBindTexture(layer->renderTarget, layer->texture);

     glTexParameteri(layer->renderTarget, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameteri(layer->renderTarget, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

     glTexParameteri(layer->renderTarget, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(layer->renderTarget, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 }

 Layer* LayerRenderer::createTextureLayer(bool isOpaque) {
     LAYER_RENDERER_LOGD("Creating new texture layer");

     Layer* layer = new Layer(0, 0);
     layer->isCacheable = false;
     layer->isTextureLayer = true;
     layer->blend = !isOpaque;
     layer->empty = true;
     layer->fbo = 0;
     layer->colorFilter = NULL;
     layer->fbo = 0;
     layer->layer.set(0.0f, 0.0f, 0.0f, 0.0f);
     layer->texCoords.set(0.0f, 1.0f, 0.0f, 1.0f);
     layer->alpha = 255;
     layer->mode = SkXfermode::kSrcOver_Mode;
     layer->colorFilter = NULL;
     layer->region.clear();
     layer->renderTarget = GL_NONE; // see ::updateTextureLayer()

     glActiveTexture(GL_TEXTURE0);
     glGenTextures(1, &layer->texture);

     return layer;
 }

 void LayerRenderer::updateTextureLayer(Layer* layer, uint32_t width, uint32_t height,
         bool isOpaque, GLenum renderTarget, float* transform) {
     if (layer) {
         layer->blend = !isOpaque;
         layer->width = width;
         layer->height = height;
         layer->layer.set(0.0f, 0.0f, width, height);
         layer->region.set(width, height);
         layer->regionRect.set(0.0f, 0.0f, width, height);
         layer->texTransform.load(transform);

         if (renderTarget != layer->renderTarget) {
             layer->renderTarget = renderTarget;
             setTextureParameters(layer);
         }
     }
 }

 void LayerRenderer::destroyLayer(Layer* layer) {
     if (layer) {
         LAYER_RENDERER_LOGD("Destroying layer, fbo = %d", layer->fbo);

         if (layer->fbo) {
             Caches::getInstance().fboCache.put(layer->fbo);
         }

         if (!Caches::getInstance().layerCache.put(layer)) {
             if (layer->texture) glDeleteTextures(1, &layer->texture);
             delete layer;
         } else {
             layer->region.clear();
         }
     }
 }

 void LayerRenderer::destroyLayerDeferred(Layer* layer) {
     if (layer) {
         LAYER_RENDERER_LOGD("Deferring layer destruction, fbo = %d", layer->fbo);

         Caches::getInstance().deleteLayerDeferred(layer);
     }
 }

 bool LayerRenderer::copyLayer(Layer* layer, SkBitmap* bitmap) {
     Caches& caches = Caches::getInstance();
     if (layer && layer->isTextureLayer && bitmap->width() <= caches.maxTextureSize &&
             bitmap->height() <= caches.maxTextureSize) {

         GLuint fbo = caches.fboCache.get();
         if (!fbo) {
             LOGW("Could not obtain an FBO");
             return false;
         }

         SkAutoLockPixels alp(*bitmap);

         GLuint texture;
         GLuint previousFbo;

         GLenum format;
         GLenum type;

         GLenum error = GL_NO_ERROR;
         bool status = false;

         switch (bitmap->config()) {
             case SkBitmap::kA8_Config:
                 format = GL_ALPHA;
                 type = GL_UNSIGNED_BYTE;
                 break;
             case SkBitmap::kRGB_565_Config:
                 format = GL_RGB;
                 type = GL_UNSIGNED_SHORT_5_6_5;
                 break;
             case SkBitmap::kARGB_4444_Config:
                 format = GL_RGBA;
                 type = GL_UNSIGNED_SHORT_4_4_4_4;
                 break;
             case SkBitmap::kARGB_8888_Config:
             default:
                 format = GL_RGBA;
                 type = GL_UNSIGNED_BYTE;
                 break;
         }

         float alpha = layer->alpha;
         SkXfermode::Mode mode = layer->mode;

         layer->mode = SkXfermode::kSrc_Mode;
         layer->alpha = 255;
         layer->fbo = fbo;

         glGetIntegerv(GL_FRAMEBUFFER_BINDING, (GLint*) &previousFbo);
         glBindFramebuffer(GL_FRAMEBUFFER, fbo);

         glGenTextures(1, &texture);
         if ((error = glGetError()) != GL_NO_ERROR) goto error;

         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, texture);

         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

         glTexImage2D(GL_TEXTURE_2D, 0, format, bitmap->width(), bitmap->height(),
                 0, format, type, NULL);
         if ((error = glGetError()) != GL_NO_ERROR) goto error;

         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
                 GL_TEXTURE_2D, texture, 0);
         if ((error = glGetError()) != GL_NO_ERROR) goto error;

         {
             LayerRenderer renderer(layer);
             renderer.setViewport(bitmap->width(), bitmap->height());
             renderer.OpenGLRenderer::prepareDirty(0.0f, 0.0f,
                     bitmap->width(), bitmap->height(), !layer->blend);
             if ((error = glGetError()) != GL_NO_ERROR) goto error;

             {
                 Rect bounds;
                 bounds.set(0.0f, 0.0f, bitmap->width(), bitmap->height());
                 renderer.drawTextureLayer(layer, bounds);

                 glReadPixels(0, 0, bitmap->width(), bitmap->height(), format,
                         type, bitmap->getPixels());

                 if ((error = glGetError()) != GL_NO_ERROR) goto error;
             }

             status = true;
         }

 error:
 #if DEBUG_OPENGL
         if (error != GL_NO_ERROR) {
             LOGD("GL error while copying layer into bitmap = 0x%x", error);
         }
 #endif

         glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
         layer->mode = mode;
         layer->alpha = alpha;
         layer->fbo = 0;
         glDeleteTextures(1, &texture);
         caches.fboCache.put(fbo);

         return status;
     }
     return false;
 }

 }; // namespace uirenderer
 }; // namespace android
	/*
	* Copyright (C) 2011 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 <ui/Rect.h>

	#include "LayerCache.h"
	#include "LayerRenderer.h"
	#include "Matrix.h"
	#include "Properties.h"
	#include "Rect.h"

	namespace android {
	namespace uirenderer {

	///////////////////////////////////////////////////////////////////////////////
	// Rendering
	///////////////////////////////////////////////////////////////////////////////

	void LayerRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
	LAYER_RENDERER_LOGD("Rendering into layer, fbo = %d", mLayer->fbo);

	glBindFramebuffer(GL_FRAMEBUFFER, mLayer->fbo);

	const float width = mLayer->layer.getWidth();
	const float height = mLayer->layer.getHeight();

	#if RENDER_LAYERS_AS_REGIONS
	Rect dirty(left, top, right, bottom);
	if (dirty.isEmpty() \|\| (dirty.left <= 0 && dirty.top <= 0 &&
	dirty.right >= width && dirty.bottom >= height)) {
	mLayer->region.clear();
	dirty.set(0.0f, 0.0f, width, height);
	} else {
	dirty.intersect(0.0f, 0.0f, width, height);
	android::Rect r(dirty.left, dirty.top, dirty.right, dirty.bottom);
	mLayer->region.subtractSelf(r);
	}

	OpenGLRenderer::prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, opaque);
	#else
	OpenGLRenderer::prepareDirty(0.0f, 0.0f, width, height, opaque);
	#endif
	}

	void LayerRenderer::finish() {
	OpenGLRenderer::finish();

	generateMesh();

	LAYER_RENDERER_LOGD("Finished rendering into layer, fbo = %d", mLayer->fbo);

	// No need to unbind our FBO, this will be taken care of by the caller
	// who will invoke OpenGLRenderer::resume()
	}

	GLint LayerRenderer::getTargetFbo() {
	return mLayer->fbo;
	}

	///////////////////////////////////////////////////////////////////////////////
	// Dirty region tracking
	///////////////////////////////////////////////////////////////////////////////

	bool LayerRenderer::hasLayer() {
	return true;
	}

	Region* LayerRenderer::getRegion() {
	#if RENDER_LAYERS_AS_REGIONS
	if (getSnapshot()->flags & Snapshot::kFlagFboTarget) {
	return OpenGLRenderer::getRegion();
	}
	return &mLayer->region;
	#else
	return OpenGLRenderer::getRegion();
	#endif
	}

	void LayerRenderer::generateMesh() {
	#if RENDER_LAYERS_AS_REGIONS
	if (mLayer->region.isRect() \|\| mLayer->region.isEmpty()) {
	if (mLayer->mesh) {
	delete mLayer->mesh;
	delete mLayer->meshIndices;

	mLayer->mesh = NULL;
	mLayer->meshIndices = NULL;
	mLayer->meshElementCount = 0;
	}

	mLayer->setRegionAsRect();
	return;
	}

	size_t count;
	const android::Rect* rects = mLayer->region.getArray(&count);

	GLsizei elementCount = count * 6;

	if (mLayer->mesh && mLayer->meshElementCount < elementCount) {
	delete mLayer->mesh;
	delete mLayer->meshIndices;

	mLayer->mesh = NULL;
	mLayer->meshIndices = NULL;
	}

	bool rebuildIndices = false;
	if (!mLayer->mesh) {
	mLayer->mesh = new TextureVertex[count * 4];
	mLayer->meshIndices = new uint16_t[elementCount];
	rebuildIndices = true;
	}
	mLayer->meshElementCount = elementCount;

	const float texX = 1.0f / float(mLayer->width);
	const float texY = 1.0f / float(mLayer->height);
	const float height = mLayer->layer.getHeight();

	TextureVertex* mesh = mLayer->mesh;
	uint16_t* indices = mLayer->meshIndices;

	for (size_t i = 0; i < count; i++) {
	const android::Rect* r = &rects[i];

	const float u1 = r->left * texX;
	const float v1 = (height - r->top) * texY;
	const float u2 = r->right * texX;
	const float v2 = (height - r->bottom) * texY;

	TextureVertex::set(mesh++, r->left, r->top, u1, v1);
	TextureVertex::set(mesh++, r->right, r->top, u2, v1);
	TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
	TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);

	if (rebuildIndices) {
	uint16_t quad = i * 4;
	int index = i * 6;
	indices[index ] = quad; // top-left
	indices[index + 1] = quad + 1; // top-right
	indices[index + 2] = quad + 2; // bottom-left
	indices[index + 3] = quad + 2; // bottom-left
	indices[index + 4] = quad + 1; // top-right
	indices[index + 5] = quad + 3; // bottom-right
	}
	}
	#endif
	}

	///////////////////////////////////////////////////////////////////////////////
	// Layers management
	///////////////////////////////////////////////////////////////////////////////

	Layer* LayerRenderer::createLayer(uint32_t width, uint32_t height, bool isOpaque) {
	LAYER_RENDERER_LOGD("Creating new layer %dx%d", width, height);

	GLuint fbo = Caches::getInstance().fboCache.get();
	if (!fbo) {
	LOGW("Could not obtain an FBO");
	return NULL;
	}

	glActiveTexture(GL_TEXTURE0);
	Layer* layer = Caches::getInstance().layerCache.get(width, height);
	if (!layer) {
	LOGW("Could not obtain a layer");
	return NULL;
	}

	layer->fbo = fbo;
	layer->layer.set(0.0f, 0.0f, width, height);
	layer->texCoords.set(0.0f, height / float(layer->height),
	width / float(layer->width), 0.0f);
	layer->alpha = 255;
	layer->mode = SkXfermode::kSrcOver_Mode;
	layer->blend = !isOpaque;
	layer->colorFilter = NULL;
	layer->region.clear();

	GLuint previousFbo;
	glGetIntegerv(GL_FRAMEBUFFER_BINDING, (GLint*) &previousFbo);

	glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
	glBindTexture(GL_TEXTURE_2D, layer->texture);

	// Initialize the texture if needed
	if (layer->empty) {
	layer->empty = false;
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
	GL_RGBA, GL_UNSIGNED_BYTE, NULL);

	if (glGetError() != GL_NO_ERROR) {
	LOGD("Could not allocate texture");
	glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
	glDeleteTextures(1, &layer->texture);
	Caches::getInstance().fboCache.put(fbo);
	delete layer;
	return NULL;
	}
	}

	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
	layer->texture, 0);

	glDisable(GL_SCISSOR_TEST);
	glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
	glClear(GL_COLOR_BUFFER_BIT);
	glEnable(GL_SCISSOR_TEST);

	glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);

	return layer;
	}

	bool LayerRenderer::resizeLayer(Layer* layer, uint32_t width, uint32_t height) {
	if (layer) {
	LAYER_RENDERER_LOGD("Resizing layer fbo = %d to %dx%d", layer->fbo, width, height);

	if (Caches::getInstance().layerCache.resize(layer, width, height)) {
	layer->layer.set(0.0f, 0.0f, width, height);
	layer->texCoords.set(0.0f, height / float(layer->height),
	width / float(layer->width), 0.0f);
	} else {
	if (layer->texture) glDeleteTextures(1, &layer->texture);
	delete layer;
	return false;
	}
	}

	return true;
	}

	static void setTextureParameters(Layer* layer) {
	glBindTexture(layer->renderTarget, layer->texture);

	glTexParameteri(layer->renderTarget, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(layer->renderTarget, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

	glTexParameteri(layer->renderTarget, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(layer->renderTarget, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
	}

	Layer* LayerRenderer::createTextureLayer(bool isOpaque) {
	LAYER_RENDERER_LOGD("Creating new texture layer");

	Layer* layer = new Layer(0, 0);
	layer->isCacheable = false;
	layer->isTextureLayer = true;
	layer->blend = !isOpaque;
	layer->empty = true;
	layer->fbo = 0;
	layer->colorFilter = NULL;
	layer->fbo = 0;
	layer->layer.set(0.0f, 0.0f, 0.0f, 0.0f);
	layer->texCoords.set(0.0f, 1.0f, 0.0f, 1.0f);
	layer->alpha = 255;
	layer->mode = SkXfermode::kSrcOver_Mode;
	layer->colorFilter = NULL;
	layer->region.clear();
	layer->renderTarget = GL_NONE; // see ::updateTextureLayer()

	glActiveTexture(GL_TEXTURE0);
	glGenTextures(1, &layer->texture);

	return layer;
	}

	void LayerRenderer::updateTextureLayer(Layer* layer, uint32_t width, uint32_t height,
	bool isOpaque, GLenum renderTarget, float* transform) {
	if (layer) {
	layer->blend = !isOpaque;
	layer->width = width;
	layer->height = height;
	layer->layer.set(0.0f, 0.0f, width, height);
	layer->region.set(width, height);
	layer->regionRect.set(0.0f, 0.0f, width, height);
	layer->texTransform.load(transform);

	if (renderTarget != layer->renderTarget) {
	layer->renderTarget = renderTarget;
	setTextureParameters(layer);
	}
	}
	}

	void LayerRenderer::destroyLayer(Layer* layer) {
	if (layer) {
	LAYER_RENDERER_LOGD("Destroying layer, fbo = %d", layer->fbo);

	if (layer->fbo) {
	Caches::getInstance().fboCache.put(layer->fbo);
	}

	if (!Caches::getInstance().layerCache.put(layer)) {
	if (layer->texture) glDeleteTextures(1, &layer->texture);
	delete layer;
	} else {
	layer->region.clear();
	}
	}
	}

	void LayerRenderer::destroyLayerDeferred(Layer* layer) {
	if (layer) {
	LAYER_RENDERER_LOGD("Deferring layer destruction, fbo = %d", layer->fbo);

	Caches::getInstance().deleteLayerDeferred(layer);
	}
	}

	bool LayerRenderer::copyLayer(Layer* layer, SkBitmap* bitmap) {
	Caches& caches = Caches::getInstance();
	if (layer && layer->isTextureLayer && bitmap->width() <= caches.maxTextureSize &&
	bitmap->height() <= caches.maxTextureSize) {

	GLuint fbo = caches.fboCache.get();
	if (!fbo) {
	LOGW("Could not obtain an FBO");
	return false;
	}

	SkAutoLockPixels alp(*bitmap);

	GLuint texture;
	GLuint previousFbo;

	GLenum format;
	GLenum type;

	GLenum error = GL_NO_ERROR;
	bool status = false;

	switch (bitmap->config()) {
	case SkBitmap::kA8_Config:
	format = GL_ALPHA;
	type = GL_UNSIGNED_BYTE;
	break;
	case SkBitmap::kRGB_565_Config:
	format = GL_RGB;
	type = GL_UNSIGNED_SHORT_5_6_5;
	break;
	case SkBitmap::kARGB_4444_Config:
	format = GL_RGBA;
	type = GL_UNSIGNED_SHORT_4_4_4_4;
	break;
	case SkBitmap::kARGB_8888_Config:
	default:
	format = GL_RGBA;
	type = GL_UNSIGNED_BYTE;
	break;
	}

	float alpha = layer->alpha;
	SkXfermode::Mode mode = layer->mode;

	layer->mode = SkXfermode::kSrc_Mode;
	layer->alpha = 255;
	layer->fbo = fbo;

	glGetIntegerv(GL_FRAMEBUFFER_BINDING, (GLint*) &previousFbo);
	glBindFramebuffer(GL_FRAMEBUFFER, fbo);

	glGenTextures(1, &texture);
	if ((error = glGetError()) != GL_NO_ERROR) goto error;

	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, texture);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

	glTexImage2D(GL_TEXTURE_2D, 0, format, bitmap->width(), bitmap->height(),
	0, format, type, NULL);
	if ((error = glGetError()) != GL_NO_ERROR) goto error;

	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
	GL_TEXTURE_2D, texture, 0);
	if ((error = glGetError()) != GL_NO_ERROR) goto error;

	{
	LayerRenderer renderer(layer);
	renderer.setViewport(bitmap->width(), bitmap->height());
	renderer.OpenGLRenderer::prepareDirty(0.0f, 0.0f,
	bitmap->width(), bitmap->height(), !layer->blend);
	if ((error = glGetError()) != GL_NO_ERROR) goto error;

	{
	Rect bounds;
	bounds.set(0.0f, 0.0f, bitmap->width(), bitmap->height());
	renderer.drawTextureLayer(layer, bounds);

	glReadPixels(0, 0, bitmap->width(), bitmap->height(), format,
	type, bitmap->getPixels());

	if ((error = glGetError()) != GL_NO_ERROR) goto error;
	}

	status = true;
	}

	error:
	#if DEBUG_OPENGL
	if (error != GL_NO_ERROR) {
	LOGD("GL error while copying layer into bitmap = 0x%x", error);
	}
	#endif

	glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
	layer->mode = mode;
	layer->alpha = alpha;
	layer->fbo = 0;
	glDeleteTextures(1, &texture);
	caches.fboCache.put(fbo);

	return status;
	}
	return false;
	}

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