diff --git a/libs/surfaceflinger/LayerBase.h b/libs/surfaceflinger/LayerBase.h
new file mode 100644
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+++ b/libs/surfaceflinger/LayerBase.h
@@ -0,0 +1,356 @@
+/*
+ * Copyright (C) 2007 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_LAYER_BASE_H
+#define ANDROID_LAYER_BASE_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <private/ui/LayerState.h>
+
+#include <ui/Region.h>
+#include <ui/Overlay.h>
+
+#include <pixelflinger/pixelflinger.h>
+
+#include "Transform.h"
+
+namespace android {
+
+// ---------------------------------------------------------------------------
+
+class SurfaceFlinger;
+class DisplayHardware;
+class GraphicPlane;
+class Client;
+
+// ---------------------------------------------------------------------------
+
+class LayerBase
+{
+    // poor man's dynamic_cast below
+    template<typename T>
+    struct getTypeInfoOfAnyType {
+        static uint32_t get() { return T::typeInfo; }
+    };
+
+    template<typename T>
+    struct getTypeInfoOfAnyType<T*> {
+        static uint32_t get() { return getTypeInfoOfAnyType<T>::get(); }
+    };
+
+public:
+    static const uint32_t typeInfo;
+    static const char* const typeID;
+    virtual char const* getTypeID() const { return typeID; }
+    virtual uint32_t getTypeInfo() const { return typeInfo; }
+    
+    template<typename T>
+    static T dynamicCast(LayerBase* base) {
+        uint32_t mostDerivedInfo = base->getTypeInfo();
+        uint32_t castToInfo = getTypeInfoOfAnyType<T>::get();
+        if ((mostDerivedInfo & castToInfo) == castToInfo)
+            return static_cast<T>(base);
+        return 0;
+    }
+
+    
+    static Vector<GLuint> deletedTextures; 
+
+    LayerBase(SurfaceFlinger* flinger, DisplayID display);
+    virtual ~LayerBase();
+    
+    DisplayID           dpy;
+    mutable bool        contentDirty;
+            Region      visibleRegionScreen;
+            Region      transparentRegionScreen;
+            Region      coveredRegionScreen;
+            
+            struct State {
+                uint32_t        w;
+                uint32_t        h;
+                uint32_t        z;
+                uint8_t         alpha;
+                uint8_t         flags;
+                uint8_t         reserved[2];
+                int32_t         sequence;   // changes when visible regions can change
+                uint32_t        tint;
+                Transform       transform;
+                Region          transparentRegion;
+            };
+
+            // modify current state
+            bool setPosition(int32_t x, int32_t y);
+            bool setLayer(uint32_t z);
+            bool setSize(uint32_t w, uint32_t h);
+            bool setAlpha(uint8_t alpha);
+            bool setMatrix(const layer_state_t::matrix22_t& matrix);
+            bool setTransparentRegionHint(const Region& opaque);
+            bool setFlags(uint8_t flags, uint8_t mask);
+            
+            void commitTransaction(bool skipSize);
+            bool requestTransaction();
+            void forceVisibilityTransaction();
+            
+            uint32_t getTransactionFlags(uint32_t flags);
+            uint32_t setTransactionFlags(uint32_t flags);
+            
+            Rect visibleBounds() const;
+            void drawRegion(const Region& reg) const;
+
+            void invalidate();
+            
+    /**
+     * draw - performs some global clipping optimizations
+     * and calls onDraw().
+     * Typically this method is not overridden, instead implement onDraw()
+     * to perform the actual drawing.  
+     */
+    virtual void draw(const Region& clip) const;
+    
+    /**
+     * onDraw - draws the surface.
+     */
+    virtual void onDraw(const Region& clip) const = 0;
+    
+    /**
+     * initStates - called just after construction
+     */
+    virtual void initStates(uint32_t w, uint32_t h, uint32_t flags);
+    
+    /**
+     * setSizeChanged - called when the *current* state's size is changed.
+     */
+    virtual void setSizeChanged(uint32_t w, uint32_t h);
+    
+    /**
+     * doTransaction - process the transaction. This is a good place to figure
+     * out which attributes of the surface have changed.
+     */
+    virtual uint32_t doTransaction(uint32_t transactionFlags);
+    
+    /**
+     * setVisibleRegion - called to set the new visible region. This gives
+     * a chance to update the new visible region or record the fact it changed.
+     */
+    virtual void setVisibleRegion(const Region& visibleRegion);
+    
+    /**
+     * setCoveredRegion - called when the covered region changes. The covered
+     * region correspond to any area of the surface that is covered 
+     * (transparently or not) by another surface.
+     */
+    virtual void setCoveredRegion(const Region& coveredRegion);
+    
+    /**
+     * getPhysicalSize - returns the physical size of the drawing state of
+     * the surface. If the surface is backed by a bitmap, this is the size of
+     * the bitmap (as opposed to the size of the drawing state).
+     */
+    virtual Point getPhysicalSize() const;
+
+    /**
+     * validateVisibility - cache a bunch of things
+     */
+    virtual void validateVisibility(const Transform& globalTransform);
+
+    /**
+     * lockPageFlip - called each time the screen is redrawn and returns whether
+     * the visible regions need to be recomputed (this is a fairly heavy
+     * operation, so this should be set only if needed). Typically this is used
+     * to figure out if the content or size of a surface has changed.
+     */
+    virtual void lockPageFlip(bool& recomputeVisibleRegions);
+    
+    /**
+     * unlockPageFlip - called each time the screen is redrawn. updates the
+     * final dirty region wrt the planeTransform.
+     * At this point, all visible regions, surface position and size, etc... are
+     * correct.
+     */
+    virtual void unlockPageFlip(const Transform& planeTransform, Region& outDirtyRegion);
+    
+    /**
+     * finishPageFlip - called after all surfaces have drawn.
+     */
+    virtual void finishPageFlip();
+    
+    /**
+     * needsBlending - true if this surface needs blending
+     */
+    virtual bool needsBlending() const  { return false; }
+
+    /**
+     * transformed -- true is this surface needs a to be transformed
+     */
+    virtual bool transformed() const    { return mTransformed; }
+
+    /**
+     * isSecure - true if this surface is secure, that is if it prevents
+     * screenshots or vns servers.
+     */
+    virtual bool isSecure() const       { return false; }
+
+            enum { // flags for doTransaction()
+                eVisibleRegion      = 0x00000002,
+                eRestartTransaction = 0x00000008
+            };
+
+
+    inline  const State&    drawingState() const    { return mDrawingState; }
+    inline  const State&    currentState() const    { return mCurrentState; }
+    inline  State&          currentState()          { return mCurrentState; }
+
+    static int compareCurrentStateZ(LayerBase*const* layerA, LayerBase*const* layerB) {
+        return layerA[0]->currentState().z - layerB[0]->currentState().z;
+    }
+
+    int32_t  getOrientation() const { return mOrientation; }
+    int  tx() const             { return mLeft; }
+    int  ty() const             { return mTop; }
+    
+protected:
+    const GraphicPlane& graphicPlane(int dpy) const;
+          GraphicPlane& graphicPlane(int dpy);
+
+          GLuint createTexture() const;
+    
+          void drawWithOpenGL(const Region& clip,
+                  GLint textureName,
+                  const GGLSurface& surface,
+                  int transform = 0) const;
+
+          void clearWithOpenGL(const Region& clip) const;
+
+          void loadTexture(const Region& dirty,
+                  GLint textureName, const GGLSurface& t,
+                  GLuint& textureWidth, GLuint& textureHeight) const;
+
+          bool canUseCopybit() const;
+          
+                SurfaceFlinger* mFlinger;
+                uint32_t        mFlags;
+
+                // cached during validateVisibility()
+                bool            mTransformed;
+                int32_t         mOrientation;
+                GLfixed         mVertices[4][2];
+                Rect            mTransformedBounds;
+                bool            mCanUseCopyBit;
+                int             mLeft;
+                int             mTop;
+            
+                // these are protected by an external lock
+                State           mCurrentState;
+                State           mDrawingState;
+    volatile    int32_t         mTransactionFlags;
+
+                // don't change, don't need a lock
+                bool            mPremultipliedAlpha;
+
+                // only read
+    const       uint32_t        mIdentity;
+     
+                // atomic
+    volatile    int32_t         mInvalidate;
+                
+
+private:
+                void validateTexture(GLint textureName) const;
+    static      int32_t         sIdentity;
+};
+
+
+// ---------------------------------------------------------------------------
+
+class LayerBaseClient : public LayerBase
+{
+public:
+    class Surface;
+   static const uint32_t typeInfo;
+    static const char* const typeID;
+    virtual char const* getTypeID() const { return typeID; }
+    virtual uint32_t getTypeInfo() const { return typeInfo; }
+
+    LayerBaseClient(SurfaceFlinger* flinger, DisplayID display, 
+            Client* client, int32_t i);
+    virtual ~LayerBaseClient();
+
+
+    Client*             const client;
+    layer_cblk_t*       const lcblk;
+
+    inline  int32_t     clientIndex() const { return mIndex; }
+            int32_t     serverIndex() const;
+
+    virtual sp<Surface> getSurface() const;
+   
+            uint32_t    getIdentity() const { return mIdentity; }
+
+    class Surface : public BnSurface 
+    {
+    public:
+        Surface(SurfaceID id, int identity) { 
+            mParams.token = id;
+            mParams.identity = identity;
+        }
+        Surface(SurfaceID id, 
+                const sp<IMemoryHeap>& heap0,
+                const sp<IMemoryHeap>& heap1,
+                int identity)
+        {
+            mParams.token = id;
+            mParams.identity = identity;
+            mParams.heap[0] = heap0;
+            mParams.heap[1] = heap1;
+        }
+        virtual ~Surface() {
+            // TODO: We now have a point here were we can clean-up the
+            // client's mess.
+            // This is also where surface id should be recycled.
+            //LOGD("Surface %d, heaps={%p, %p} destroyed",
+            //        mId, mHeap[0].get(), mHeap[1].get());
+        }
+
+        virtual void getSurfaceData(
+                ISurfaceFlingerClient::surface_data_t* params) const {
+            *params = mParams;
+        }
+
+        virtual status_t registerBuffers(const ISurface::BufferHeap& buffers) 
+                { return INVALID_OPERATION; }
+        virtual void postBuffer(ssize_t offset) { }
+        virtual void unregisterBuffers() { };
+        virtual sp<OverlayRef> createOverlay(
+                uint32_t w, uint32_t h, int32_t format) {
+            return NULL;
+        };
+
+    private:
+        ISurfaceFlingerClient::surface_data_t mParams;
+    };
+
+private:
+    int32_t mIndex;
+
+};
+
+// ---------------------------------------------------------------------------
+
+}; // namespace android
+
+#endif // ANDROID_LAYER_BASE_H