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diff --git a/libs/hwui/RenderBuffer.h b/libs/hwui/RenderBuffer.h
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+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef ANDROID_HWUI_RENDER_BUFFER_H
+#define ANDROID_HWUI_RENDER_BUFFER_H
+
+#include <GLES2/gl2.h>
+#include <GLES2/gl2ext.h>
+
+namespace android {
+namespace uirenderer {
+
+/**
+ * Represents an OpenGL render buffer. Render buffers are attached
+ * to layers to perform stencil work.
+ */
+struct RenderBuffer {
+    /**
+     * Creates a new render buffer in the specified format and dimensions.
+     * The format must be one of the formats allowed by glRenderbufferStorage().
+     */
+    RenderBuffer(GLenum format, uint32_t width, uint32_t height):
+        mFormat(format), mWidth(width), mHeight(height), mAllocated(false) {
+
+        glGenRenderbuffers(1, &mName);
+    }
+
+    ~RenderBuffer() {
+        if (mName && mAllocated) {
+            glDeleteRenderbuffers(1, &mName);
+        }
+    }
+
+    /**
+     * Returns the GL name of this render buffer.
+     */
+    GLuint getName() const {
+        return mName;
+    }
+
+    /**
+     * Returns the format of this render buffer.
+     */
+    GLenum getFormat() const {
+        return mFormat;
+    }
+
+    /**
+     * Binds this render buffer to the current GL context.
+     */
+    void bind() const {
+        glBindRenderbuffer(GL_RENDERBUFFER, mName);
+    }
+
+    /**
+     * Indicates whether this render buffer has allocated its
+     * storage. See allocate() and resize().
+     */
+    bool isAllocated() const {
+        return mAllocated;
+    }
+
+    /**
+     * Allocates this render buffer's storage if needed.
+     * This method doesn't do anything if isAllocated() returns true.
+     */
+    void allocate() {
+        if (!mAllocated) {
+            glRenderbufferStorage(GL_RENDERBUFFER, mFormat, mWidth, mHeight);
+            mAllocated = true;
+        }
+    }
+
+    /**
+     * Resizes this render buffer. If the buffer was previously allocated,
+     * the storage is re-allocated wit the new specified dimensions. If the
+     * buffer wasn't previously allocated, the buffer remains unallocated.
+     */
+    void resize(uint32_t width, uint32_t height) {
+        if (isAllocated() && (width != mWidth || height != mHeight)) {
+            glRenderbufferStorage(GL_RENDERBUFFER, mFormat, width, height);
+        }
+
+        mWidth = width;
+        mHeight = height;
+    }
+
+    /**
+     * Returns the width of the render buffer in pixels.
+     */
+    uint32_t getWidth() const {
+        return mWidth;
+    }
+
+    /**
+     * Returns the height of the render buffer in pixels.
+     */
+    uint32_t getHeight() const {
+        return mHeight;
+    }
+
+    /**
+     * Returns the size of this render buffer in bytes.
+     */
+    uint32_t getSize() const {
+        // Round to the nearest byte
+        return (uint32_t) ((mWidth * mHeight * formatSize(mFormat)) / 8.0f + 0.5f);
+    }
+
+    /**
+     * Returns the number of bits per component in the specified format.
+     * The format must be one of the formats allowed by glRenderbufferStorage().
+     */
+    static uint32_t formatSize(GLenum format) {
+        switch (format) {
+            case GL_STENCIL_INDEX8:
+                return 8;
+            case GL_STENCIL_INDEX1_OES:
+                return 1;
+            case GL_STENCIL_INDEX4_OES:
+                return 4;
+            case GL_DEPTH_COMPONENT16:
+            case GL_RGBA4:
+            case GL_RGB565:
+            case GL_RGB5_A1:
+                return 16;
+        }
+        return 0;
+    }
+
+    /**
+     * Indicates whether the specified format represents a stencil buffer.
+     */
+    static bool isStencilBuffer(GLenum format) {
+        switch (format) {
+            case GL_STENCIL_INDEX8:
+            case GL_STENCIL_INDEX1_OES:
+            case GL_STENCIL_INDEX4_OES:
+                return true;
+        }
+        return false;
+    }
+
+private:
+    GLenum mFormat;
+
+    uint32_t mWidth;
+    uint32_t mHeight;
+
+    bool mAllocated;
+
+    GLuint mName;
+}; // struct RenderBuffer
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif // ANDROID_HWUI_RENDER_BUFFER_H