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diff --git a/libs/hwui/PixelBuffer.h b/libs/hwui/PixelBuffer.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_PIXEL_BUFFER_H
+#define ANDROID_HWUI_PIXEL_BUFFER_H
+
+#include <GLES3/gl3.h>
+
+namespace android {
+namespace uirenderer {
+
+/**
+ * Represents a pixel buffer. A pixel buffer will be backed either by a
+ * PBO on OpenGL ES 3.0 and higher or by an array of uint8_t on other
+ * versions. If the buffer is backed by a PBO it will of type
+ * GL_PIXEL_UNPACK_BUFFER.
+ *
+ * To read from or write into a PixelBuffer you must first map the
+ * buffer using the map(AccessMode) method. This method returns a
+ * pointer to the beginning of the buffer.
+ *
+ * Before the buffer can be used by the GPU, for instance to upload
+ * a texture, you must first unmap the buffer. To do so, call the
+ * unmap() method.
+ *
+ * Mapping and unmapping a PixelBuffer can have the side effect of
+ * changing the currently active GL_PIXEL_UNPACK_BUFFER. It is
+ * therefore recommended to call Caches::unbindPixelbuffer() after
+ * using a PixelBuffer to upload to a texture.
+ */
+class PixelBuffer {
+public:
+    enum BufferType {
+        kBufferType_Auto,
+        kBufferType_CPU
+    };
+
+    enum AccessMode {
+        kAccessMode_None = 0,
+        kAccessMode_Read = GL_MAP_READ_BIT,
+        kAccessMode_Write = GL_MAP_WRITE_BIT,
+        kAccessMode_ReadWrite = GL_MAP_READ_BIT | GL_MAP_WRITE_BIT
+    };
+
+    /**
+     * Creates a new PixelBuffer object with the specified format and
+     * dimensions. The buffer is immediately allocated.
+     *
+     * The buffer type specifies how the buffer should be allocated.
+     * By default this method will automatically choose whether to allocate
+     * a CPU or GPU buffer.
+     */
+    static PixelBuffer* create(GLenum format, uint32_t width, uint32_t height,
+            BufferType type = kBufferType_Auto);
+
+    virtual ~PixelBuffer() {
+    }
+
+    /**
+     * Returns the format of this render buffer.
+     */
+    GLenum getFormat() const {
+        return mFormat;
+    }
+
+    /**
+     * Maps this before with the specified access mode. This method
+     * returns a pointer to the region of memory where the buffer was
+     * mapped.
+     *
+     * If the buffer is already mapped when this method is invoked,
+     * this method will return the previously mapped pointer. The
+     * access mode can only be changed by calling unmap() first.
+     *
+     * The specified access mode cannot be kAccessMode_None.
+     */
+    virtual uint8_t* map(AccessMode mode = kAccessMode_ReadWrite) = 0;
+
+    /**
+     * Unmaps this buffer, if needed. After the buffer is unmapped,
+     * the pointer previously returned by map() becomes invalid and
+     * should not be used. After calling this method, getMappedPointer()
+     * will always return NULL.
+     */
+    virtual void unmap() = 0;
+
+    /**
+     * Returns the current access mode for this buffer. If the buffer
+     * is not mapped, this method returns kAccessMode_None.
+     */
+    AccessMode getAccessMode() const {
+        return mAccessMode;
+    }
+
+    /**
+     * Returns the currently mapped pointer. Returns NULL if the buffer
+     * is not mapped.
+     */
+    virtual uint8_t* getMappedPointer() const = 0;
+
+    /**
+     * Upload the specified rectangle of this pixe buffer as a
+     * GL_TEXTURE_2D texture. Calling this method will trigger
+     * an unmap() if necessary.
+     */
+    virtual void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) = 0;
+
+    /**
+     * 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 pixel buffer in bytes.
+     */
+    uint32_t getSize() const {
+        return mWidth * mHeight * formatSize(mFormat);
+    }
+
+    /**
+     * Returns the number of bytes per pixel in the specified format.
+     *
+     * Supported formats:
+     *      GL_ALPHA
+     *      GL_RGBA
+     */
+    static uint32_t formatSize(GLenum format) {
+        switch (format) {
+            case GL_ALPHA:
+                return 1;
+            case GL_RGBA:
+                return 4;
+        }
+        return 0;
+    }
+
+protected:
+    /**
+     * Creates a new render buffer in the specified format and dimensions.
+     * The format must be GL_ALPHA or GL_RGBA.
+     */
+    PixelBuffer(GLenum format, uint32_t width, uint32_t height):
+            mFormat(format), mWidth(width), mHeight(height), mAccessMode(kAccessMode_None) {
+    }
+
+    GLenum mFormat;
+
+    uint32_t mWidth;
+    uint32_t mHeight;
+
+    AccessMode mAccessMode;
+
+}; // class PixelBuffer
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif // ANDROID_HWUI_PIXEL_BUFFER_H