diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index 33b2f00..877b17c 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -22,10 +22,12 @@
 #include <utils/RefBase.h>
 #include <utils/String16.h>
 #include <utils/Vector.h>
+#include <utils/Flattenable.h>
 
 // ---------------------------------------------------------------------------
 namespace android {
 
+template <typename T> class LightFlattenable;
 class Flattenable;
 class IBinder;
 class IPCThreadState;
@@ -102,6 +104,10 @@
     status_t            writeWeakBinder(const wp<IBinder>& val);
     status_t            write(const Flattenable& val);
 
+    template<typename T>
+    status_t            write(const LightFlattenable<T>& val);
+
+
     // Place a native_handle into the parcel (the native_handle's file-
     // descriptors are dup'ed, so it is safe to delete the native_handle
     // when this function returns). 
@@ -153,6 +159,9 @@
     wp<IBinder>         readWeakBinder() const;
     status_t            read(Flattenable& val) const;
 
+    template<typename T>
+    status_t            read(LightFlattenable<T>& val) const;
+
     // Like Parcel.java's readExceptionCode().  Reads the first int32
     // off of a Parcel's header, returning 0 or the negative error
     // code on exceptions, but also deals with skipping over rich
@@ -267,6 +276,40 @@
 
 // ---------------------------------------------------------------------------
 
+template<typename T>
+status_t Parcel::write(const LightFlattenable<T>& val) {
+    size_t size(val.getSize());
+    if (!val.isFixedSize()) {
+        status_t err = writeInt32(size);
+        if (err != NO_ERROR) {
+            return err;
+        }
+    }
+    void* buffer = writeInplace(size);
+    return buffer == NULL ? NO_MEMORY :
+        val.flatten(buffer);
+}
+
+template<typename T>
+status_t Parcel::read(LightFlattenable<T>& val) const {
+    size_t size;
+    if (val.isFixedSize()) {
+        size = val.getSize();
+    } else {
+        int32_t s;
+        status_t err = readInt32(&s);
+        if (err != NO_ERROR) {
+            return err;
+        }
+        size = s;
+    }
+    void const* buffer = readInplace(size);
+    return buffer == NULL ? NO_MEMORY :
+        val.unflatten(buffer, size);
+}
+
+// ---------------------------------------------------------------------------
+
 inline TextOutput& operator<<(TextOutput& to, const Parcel& parcel)
 {
     parcel.print(to);
diff --git a/include/gui/Sensor.h b/include/gui/Sensor.h
index e59757a..2af2307 100644
--- a/include/gui/Sensor.h
+++ b/include/gui/Sensor.h
@@ -41,7 +41,7 @@
 
 // ----------------------------------------------------------------------------
 
-class Sensor : public ASensor, public Flattenable
+class Sensor : public ASensor, public LightFlattenable<Sensor>
 {
 public:
     enum {
@@ -54,7 +54,7 @@
 
             Sensor();
             Sensor(struct sensor_t const* hwSensor);
-    virtual ~Sensor();
+            ~Sensor();
 
     const String8& getName() const;
     const String8& getVendor() const;
@@ -68,13 +68,11 @@
     nsecs_t getMinDelayNs() const;
     int32_t getVersion() const;
 
-    // Flattenable interface
-    virtual size_t getFlattenedSize() const;
-    virtual size_t getFdCount() const;
-    virtual status_t flatten(void* buffer, size_t size,
-            int fds[], size_t count) const;
-    virtual status_t unflatten(void const* buffer, size_t size,
-            int fds[], size_t count);
+    // LightFlattenable protocol
+    inline bool isFixedSize() const { return false; }
+    size_t getSize() const;
+    status_t flatten(void* buffer) const;
+    status_t unflatten(void const* buffer, size_t size);
 
 private:
     String8 mName;
diff --git a/include/ui/Point.h b/include/ui/Point.h
index 1653120..1d7f64d 100644
--- a/include/ui/Point.h
+++ b/include/ui/Point.h
@@ -17,11 +17,12 @@
 #ifndef ANDROID_UI_POINT
 #define ANDROID_UI_POINT
 
+#include <utils/Flattenable.h>
 #include <utils/TypeHelpers.h>
 
 namespace android {
 
-class Point
+class Point : public LightFlattenablePod<Point>
 {
 public:
     int x;
diff --git a/include/ui/Rect.h b/include/ui/Rect.h
index c2c2675..47d37b6 100644
--- a/include/ui/Rect.h
+++ b/include/ui/Rect.h
@@ -17,6 +17,7 @@
 #ifndef ANDROID_UI_RECT
 #define ANDROID_UI_RECT
 
+#include <utils/Flattenable.h>
 #include <utils/TypeHelpers.h>
 #include <ui/Point.h>
 
@@ -24,7 +25,7 @@
 
 namespace android {
 
-class Rect : public ARect
+class Rect : public ARect, public LightFlattenablePod<Rect>
 {
 public:
     typedef ARect::value_type value_type;
diff --git a/include/ui/Region.h b/include/ui/Region.h
index f242f18..f0819af 100644
--- a/include/ui/Region.h
+++ b/include/ui/Region.h
@@ -23,6 +23,7 @@
 #include <utils/Vector.h>
 
 #include <ui/Rect.h>
+#include <utils/Flattenable.h>
 
 namespace android {
 // ---------------------------------------------------------------------------
@@ -30,13 +31,12 @@
 class String8;
 
 // ---------------------------------------------------------------------------
-class Region
+class Region : public LightFlattenable<Region>
 {
 public:
                         Region();
                         Region(const Region& rhs);
     explicit            Region(const Rect& rhs);
-    explicit            Region(const void* buffer);
                         ~Region();
                         
         Region& operator = (const Region& rhs);
@@ -122,12 +122,10 @@
             // be sorted in Y and X and must not make the region invalid.
             void        addRectUnchecked(int l, int t, int r, int b);
 
-            // flatten/unflatten a region to/from a raw buffer
-            ssize_t     write(void* buffer, size_t size) const;
-    static  ssize_t     writeEmpty(void* buffer, size_t size);
-
-            ssize_t     read(const void* buffer);
-    static  bool        isEmpty(void* buffer);
+    inline  bool        isFixedSize() const { return false; }
+            size_t      getSize() const;
+            status_t    flatten(void* buffer) const;
+            status_t    unflatten(void const* buffer, size_t size);
 
     void        dump(String8& out, const char* what, uint32_t flags=0) const;
     void        dump(const char* what, uint32_t flags=0) const;
diff --git a/include/utils/Flattenable.h b/include/utils/Flattenable.h
index 852be3b..e40d289 100644
--- a/include/utils/Flattenable.h
+++ b/include/utils/Flattenable.h
@@ -24,6 +24,11 @@
 
 namespace android {
 
+/*
+ * The Flattenable interface allows an object to serialize itself out
+ * to a byte-buffer and an array of file descriptors.
+ */
+
 class Flattenable
 {
 public:
@@ -56,6 +61,73 @@
 
 };
 
+/*
+ * LightFlattenable is a protocol allowing object to serialize themselves out
+ * to a byte-buffer.
+ *
+ * LightFlattenable objects must implement this protocol.
+ *
+ * LightFlattenable doesn't require the object to be virtual.
+ */
+template <typename T>
+class LightFlattenable {
+public:
+    // returns whether this object always flatten into the same size.
+    // for efficiency, this should always be inline.
+    inline bool isFixedSize() const;
+
+    // returns size in bytes of the flattened object. must be a constant.
+    inline size_t getSize() const;
+
+    // flattens the object into buffer.
+    inline status_t flatten(void* buffer) const;
+
+    // unflattens the object from buffer of given size.
+    inline status_t unflatten(void const* buffer, size_t size);
+};
+
+template <typename T>
+inline bool LightFlattenable<T>::isFixedSize() const {
+    return static_cast<T const*>(this)->T::isFixedSize();
+}
+template <typename T>
+inline size_t LightFlattenable<T>::getSize() const {
+    return static_cast<T const*>(this)->T::getSize();
+}
+template <typename T>
+inline status_t LightFlattenable<T>::flatten(void* buffer) const {
+    return static_cast<T const*>(this)->T::flatten(buffer);
+}
+template <typename T>
+inline status_t LightFlattenable<T>::unflatten(void const* buffer, size_t size) {
+    return static_cast<T*>(this)->T::unflatten(buffer, size);
+}
+
+/*
+ * LightFlattenablePod is an implementation of the LightFlattenable protocol
+ * for POD (plain-old-data) objects.
+ */
+template <typename T>
+class LightFlattenablePod : public LightFlattenable<T> {
+public:
+    inline bool isFixedSize() const {
+        return true;
+    }
+
+    inline size_t getSize() const {
+        return sizeof(T);
+    }
+    inline status_t flatten(void* buffer) const {
+        *reinterpret_cast<T*>(buffer) = *static_cast<T const*>(this);
+        return NO_ERROR;
+    }
+    inline status_t unflatten(void const* buffer, size_t) {
+        *static_cast<T*>(this) = *reinterpret_cast<T const*>(buffer);
+        return NO_ERROR;
+    }
+};
+
+
 }; // namespace android