1 files changed, 159 insertions, 0 deletions
diff --git a/libs/hwui/LayerCache.cpp b/libs/hwui/LayerCache.cpp
new file mode 100644
index 0000000..3d263a3
--- /dev/null
+++ b/libs/hwui/LayerCache.cpp
@@ -0,0 +1,159 @@
+/*
+ * 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 <GLES2/gl2.h>
+
+#include <utils/Log.h>
+
+#include "LayerCache.h"
+
+namespace android {
+namespace uirenderer {
+
+///////////////////////////////////////////////////////////////////////////////
+// Constructors/destructor
+///////////////////////////////////////////////////////////////////////////////
+
+LayerCache::LayerCache(uint32_t maxByteSize):
+        mCache(GenerationCache<LayerSize, Layer*>::kUnlimitedCapacity),
+        mIdGenerator(1), mSize(0), mMaxSize(maxByteSize) {
+}
+
+LayerCache::~LayerCache() {
+    clear();
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Size management
+///////////////////////////////////////////////////////////////////////////////
+
+uint32_t LayerCache::getSize() {
+    return mSize;
+}
+
+uint32_t LayerCache::getMaxSize() {
+    return mMaxSize;
+}
+
+void LayerCache::setMaxSize(uint32_t maxSize) {
+    mMaxSize = maxSize;
+    while (mSize > mMaxSize) {
+        Layer* oldest = mCache.removeOldest();
+        deleteLayer(oldest);
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Callbacks
+///////////////////////////////////////////////////////////////////////////////
+
+void LayerCache::operator()(LayerSize& size, Layer*& layer) {
+    deleteLayer(layer);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Caching
+///////////////////////////////////////////////////////////////////////////////
+
+void LayerCache::deleteLayer(Layer* layer) {
+    if (layer) {
+        mSize -= layer->layer.getWidth() * layer->layer.getHeight() * 4;
+
+        glDeleteFramebuffers(1, &layer->fbo);
+        glDeleteTextures(1, &layer->texture);
+        delete layer;
+    }
+}
+
+void LayerCache::clear() {
+    mCache.setOnEntryRemovedListener(this);
+    mCache.clear();
+    mCache.setOnEntryRemovedListener(NULL);
+}
+
+Layer* LayerCache::get(LayerSize& size, GLuint previousFbo) {
+    Layer* layer = mCache.remove(size);
+    if (layer) {
+        LAYER_LOGD("Reusing layer");
+
+        mSize -= layer->layer.getWidth() * layer->layer.getHeight() * 4;
+    } else {
+        LAYER_LOGD("Creating new layer");
+
+        layer = new Layer;
+        layer->blend = true;
+
+        // Generate the FBO and attach the texture
+        glGenFramebuffers(1, &layer->fbo);
+        glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
+
+        // Generate the texture in which the FBO will draw
+        glGenTextures(1, &layer->texture);
+        glBindTexture(GL_TEXTURE_2D, layer->texture);
+
+        // The FBO will not be scaled, so we can use lower quality filtering
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+        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, GL_RGBA, size.width, size.height, 0,
+                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+        // Bind texture to FBO
+        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
+                layer->texture, 0);
+
+        GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+        if (status != GL_FRAMEBUFFER_COMPLETE) {
+            LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
+
+            glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
+
+            glDeleteFramebuffers(1, &layer->fbo);
+            glDeleteTextures(1, &layer->texture);
+            delete layer;
+
+            return NULL;
+        }
+    }
+
+    return layer;
+}
+
+bool LayerCache::put(LayerSize& layerSize, Layer* layer) {
+    const uint32_t size = layerSize.width * layerSize.height * 4;
+    // Don't even try to cache a layer that's bigger than the cache
+    if (size < mMaxSize) {
+        while (mSize + size > mMaxSize) {
+            Layer* oldest = mCache.removeOldest();
+            deleteLayer(oldest);
+        }
+
+        layerSize.id = mIdGenerator++;
+        mCache.put(layerSize, layer);
+        mSize += size;
+
+        return true;
+    }
+    return false;
+}
+
+}; // namespace uirenderer
+}; // namespace android