diff --git a/libs/ui/Android.mk b/libs/ui/Android.mk
index d44d2f9..7c367ef 100644
--- a/libs/ui/Android.mk
+++ b/libs/ui/Android.mk
@@ -29,7 +29,6 @@
 	Time.cpp
 
 LOCAL_SHARED_LIBRARIES := \
-	libcorecg \
 	libcutils \
 	libutils \
 	libpixelflinger \
diff --git a/libs/ui/Region.cpp b/libs/ui/Region.cpp
index 30da911..065ed54 100644
--- a/libs/ui/Region.cpp
+++ b/libs/ui/Region.cpp
@@ -16,302 +16,653 @@
 
 #define LOG_TAG "Region"
 
-#include <stdio.h>
-#include <utils/Atomic.h>
-#include <utils/Debug.h>
+#include <utils/Log.h>
 #include <utils/String8.h>
+
+#include <ui/Rect.h>
 #include <ui/Region.h>
+#include <ui/Point.h>
+
+#include <private/ui/RegionHelper.h>
+
+// ----------------------------------------------------------------------------
+#define VALIDATE_REGIONS        (false)
+#define VALIDATE_WITH_CORECG    (false)
+// ----------------------------------------------------------------------------
+
+#if VALIDATE_WITH_CORECG
+#include <core/SkRegion.h>
+#endif
 
 namespace android {
+// ----------------------------------------------------------------------------
+
+enum {
+    op_nand = region_operator<Rect>::op_nand,
+    op_and  = region_operator<Rect>::op_and,
+    op_or   = region_operator<Rect>::op_or,
+    op_xor  = region_operator<Rect>::op_xor
+};
 
 // ----------------------------------------------------------------------------
 
 Region::Region()
+    : mBounds(0,0)
 {
 }
 
 Region::Region(const Region& rhs)
-    : mRegion(rhs.mRegion)
+    : mBounds(rhs.mBounds), mStorage(rhs.mStorage)
 {
 }
 
-Region::Region(const SkRegion& rhs)
-    : mRegion(rhs)
+Region::Region(const Rect& rhs)
+    : mBounds(rhs)
 {
 }
 
+Region::Region(const Parcel& parcel)
+{
+    status_t err = read(parcel);
+    LOGE_IF(err<0, "error %s reading Region from parcel", strerror(err));
+}
+
+Region::Region(const void* buffer)
+{
+    status_t err = read(buffer);
+    LOGE_IF(err<0, "error %s reading Region from parcel", strerror(err));
+}
+
 Region::~Region()
 {
 }
 
-Region::Region(const Rect& rhs)
-{
-    set(rhs);
-}
-
-Region::Region(const Parcel& parcel)
-{
-    read(parcel);
-}
-
-Region::Region(const void* buffer)
-{
-    read(buffer);
-}
-
 Region& Region::operator = (const Region& rhs)
 {
-    mRegion = rhs.mRegion;
+#if VALIDATE_REGIONS
+    validate(rhs, "operator=");
+#endif
+    mBounds = rhs.mBounds;
+    mStorage = rhs.mStorage;
     return *this;
 }
 
-const SkRegion& Region::toSkRegion() const
-{
-    return mRegion;
-}
-
-Rect Region::bounds() const
-{
-    const SkIRect& b(mRegion.getBounds());
-    return Rect(b.fLeft, b.fTop, b.fRight, b.fBottom);
-}
-
 void Region::clear()
 {
-    mRegion.setEmpty();
+    mBounds.clear();
+    mStorage.clear();
 }
 
 void Region::set(const Rect& r)
 {
-    SkIRect ir;
-    ir.set(r.left, r.top, r.right, r.bottom);
-    mRegion.setRect(ir);
+    mBounds = r;
+    mStorage.clear();
 }
 
 void Region::set(uint32_t w, uint32_t h)
 {
-    SkIRect ir;
-    ir.set(0, 0, w, h);
-    mRegion.setRect(ir);
+    mBounds = Rect(int(w), int(h));
+    mStorage.clear();
 }
 
 // ----------------------------------------------------------------------------
 
-Region& Region::orSelf(const Rect& r)
+void Region::addRectUnchecked(int l, int t, int r, int b)
 {
-    SkIRect ir;
-    ir.set(r.left, r.top, r.right, r.bottom);
-    mRegion.op(ir, SkRegion::kUnion_Op);
-    return *this;
+    mStorage.add(Rect(l,t,r,b));
+#if VALIDATE_REGIONS
+    validate(*this, "addRectUnchecked");
+#endif
 }
 
-Region& Region::andSelf(const Rect& r)
-{
-    SkIRect ir;
-    ir.set(r.left, r.top, r.right, r.bottom);
-    mRegion.op(ir, SkRegion::kIntersect_Op);
+// ----------------------------------------------------------------------------
+
+Region& Region::orSelf(const Rect& r) {
+    return operationSelf(r, op_or);
+}
+Region& Region::andSelf(const Rect& r) {
+    return operationSelf(r, op_and);
+}
+Region& Region::subtractSelf(const Rect& r) {
+    return operationSelf(r, op_nand);
+}
+Region& Region::operationSelf(const Rect& r, int op) {
+    Region lhs(*this);
+    boolean_operation(op, *this, lhs, r);
     return *this;
 }
 
 // ----------------------------------------------------------------------------
 
 Region& Region::orSelf(const Region& rhs) {
-    mRegion.op(rhs.mRegion, SkRegion::kUnion_Op);
-    return *this;
+    return operationSelf(rhs, op_or);
 }
-
 Region& Region::andSelf(const Region& rhs) {
-    mRegion.op(rhs.mRegion, SkRegion::kIntersect_Op);
-    return *this;
+    return operationSelf(rhs, op_and);
 }
-
 Region& Region::subtractSelf(const Region& rhs) {
-    mRegion.op(rhs.mRegion, SkRegion::kDifference_Op);
+    return operationSelf(rhs, op_nand);
+}
+Region& Region::operationSelf(const Region& rhs, int op) {
+    Region lhs(*this);
+    boolean_operation(op, *this, lhs, rhs);
     return *this;
 }
 
 Region& Region::translateSelf(int x, int y) {
-    if (x|y) mRegion.translate(x, y);
+    if (x|y) translate(*this, x, y);
     return *this;
 }
 
+// ----------------------------------------------------------------------------
+
+Region Region::merge(const Rect& rhs) const {
+    return operation(rhs, op_or);
+}
+Region Region::intersect(const Rect& rhs) const {
+    return operation(rhs, op_and);
+}
+Region Region::subtract(const Rect& rhs) const {
+    return operation(rhs, op_nand);
+}
+Region Region::operation(const Rect& rhs, int op) const {
+    Region result;
+    boolean_operation(op, result, *this, rhs);
+    return result;
+}
+
+// ----------------------------------------------------------------------------
+
 Region Region::merge(const Region& rhs) const {
-    Region result;
-    result.mRegion.op(mRegion, rhs.mRegion, SkRegion::kUnion_Op);
-    return result;
+    return operation(rhs, op_or);
 }
-
 Region Region::intersect(const Region& rhs) const {
-    Region result;
-    result.mRegion.op(mRegion, rhs.mRegion, SkRegion::kIntersect_Op);
-    return result;
+    return operation(rhs, op_and);
 }
-
 Region Region::subtract(const Region& rhs) const {
+    return operation(rhs, op_nand);
+}
+Region Region::operation(const Region& rhs, int op) const {
     Region result;
-    result.mRegion.op(mRegion, rhs.mRegion, SkRegion::kDifference_Op);
+    boolean_operation(op, result, *this, rhs);
     return result;
 }
 
 Region Region::translate(int x, int y) const {
     Region result;
-    mRegion.translate(x, y, &result.mRegion);
+    translate(result, *this, x, y);
     return result;
 }
 
 // ----------------------------------------------------------------------------
 
 Region& Region::orSelf(const Region& rhs, int dx, int dy) {
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    mRegion.op(r, SkRegion::kUnion_Op);
-    return *this;
+    return operationSelf(rhs, dx, dy, op_or);
 }
-
 Region& Region::andSelf(const Region& rhs, int dx, int dy) {
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    mRegion.op(r, SkRegion::kIntersect_Op);
+    return operationSelf(rhs, dx, dy, op_and);
+}
+Region& Region::subtractSelf(const Region& rhs, int dx, int dy) {
+    return operationSelf(rhs, dx, dy, op_nand);
+}
+Region& Region::operationSelf(const Region& rhs, int dx, int dy, int op) {
+    Region lhs(*this);
+    boolean_operation(op, *this, lhs, rhs, dx, dy);
     return *this;
 }
 
-Region& Region::subtractSelf(const Region& rhs, int dx, int dy) {
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    mRegion.op(r, SkRegion::kDifference_Op);
-    return *this;
-}
+// ----------------------------------------------------------------------------
 
 Region Region::merge(const Region& rhs, int dx, int dy) const {
-    Region result;
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    result.mRegion.op(mRegion, r, SkRegion::kUnion_Op);
-    return result;
+    return operation(rhs, dx, dy, op_or);
 }
-
 Region Region::intersect(const Region& rhs, int dx, int dy) const {
-    Region result;
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    result.mRegion.op(mRegion, r, SkRegion::kIntersect_Op);
-    return result;
+    return operation(rhs, dx, dy, op_and);
 }
-
 Region Region::subtract(const Region& rhs, int dx, int dy) const {
+    return operation(rhs, dx, dy, op_nand);
+}
+Region Region::operation(const Region& rhs, int dx, int dy, int op) const {
     Region result;
-    SkRegion r(rhs.mRegion);
-    r.translate(dx, dy);
-    result.mRegion.op(mRegion, r, SkRegion::kDifference_Op);
+    boolean_operation(op, result, *this, rhs, dx, dy);
     return result;
 }
 
 // ----------------------------------------------------------------------------
 
-Region::iterator::iterator(const Region& r)
-    : mIt(r.mRegion)
+// This is our region rasterizer, which merges rects and spans together
+// to obtain an optimal region.
+class Region::rasterizer : public region_operator<Rect>::region_rasterizer 
 {
+    Rect& bounds;
+    Vector<Rect>& storage;
+    Rect* head;
+    Rect* tail;
+    Vector<Rect> span;
+    Rect* cur;
+public:
+    rasterizer(Region& reg) 
+        : bounds(reg.mBounds), storage(reg.mStorage), head(), tail(), cur() {
+        bounds.top = bounds.bottom = 0;
+        bounds.left   = INT_MAX;
+        bounds.right  = INT_MIN;
+        storage.clear();
+    }
+
+    ~rasterizer() {
+        if (span.size()) {
+            flushSpan();
+        }
+        if (storage.size()) {
+            bounds.top = storage.itemAt(0).top;
+            bounds.bottom = storage.top().bottom;
+            if (storage.size() == 1) {
+                storage.clear();
+            }
+        } else {
+            bounds.left  = 0;
+            bounds.right = 0;
+        }
+    }
+    
+    virtual void operator()(const Rect& rect) {
+        //LOGD(">>> %3d, %3d, %3d, %3d", 
+        //        rect.left, rect.top, rect.right, rect.bottom);
+        if (span.size()) {
+            if (cur->top != rect.top) {
+                flushSpan();
+            } else if (cur->right == rect.left) {
+                cur->right = rect.right;
+                return;
+            }
+        }
+        span.add(rect);
+        cur = span.editArray() + (span.size() - 1);
+    }
+private:
+    template<typename T> 
+    static inline T min(T rhs, T lhs) { return rhs < lhs ? rhs : lhs; }
+    template<typename T> 
+    static inline T max(T rhs, T lhs) { return rhs > lhs ? rhs : lhs; }
+    void flushSpan() {
+        bool merge = false;
+        if (tail-head == ssize_t(span.size())) {
+            Rect const* p = cur;
+            Rect const* q = head;
+            if (p->top == q->bottom) {
+                merge = true;
+                while (q != tail) {
+                    if ((p->left != q->left) || (p->right != q->right)) {
+                        merge = false;
+                        break;
+                    }
+                    p++, q++;
+                }
+            }
+        }
+        if (merge) {
+            const int bottom = span[0].bottom;
+            Rect* r = head;
+            while (r != tail) {
+                r->bottom = bottom;
+                r++;
+            }
+        } else {
+            bounds.left = min(span.itemAt(0).left, bounds.left);
+            bounds.right = max(span.top().right, bounds.right);
+            storage.appendVector(span);
+            tail = storage.editArray() + storage.size();
+            head = tail - span.size();
+        }
+        span.clear();
+    }
+};
+
+bool Region::validate(const Region& reg, const char* name)
+{
+    bool result = true;
+    const_iterator cur = reg.begin();
+    const_iterator const tail = reg.end();
+    const_iterator prev = cur++;
+    Rect b(*prev);
+    while (cur != tail) {
+        b.left   = b.left   < cur->left   ? b.left   : cur->left;
+        b.top    = b.top    < cur->top    ? b.top    : cur->top;
+        b.right  = b.right  > cur->right  ? b.right  : cur->right;
+        b.bottom = b.bottom > cur->bottom ? b.bottom : cur->bottom;
+        if (cur->top == prev->top) {
+            if (cur->bottom != prev->bottom) {
+                LOGE("%s: invalid span %p", name, cur);
+                result = false;
+            } else if (cur->left < prev->right) {
+                LOGE("%s: spans overlap horizontally prev=%p, cur=%p",
+                        name, prev, cur);
+                result = false;
+            }
+        } else if (cur->top < prev->bottom) {
+            LOGE("%s: spans overlap vertically prev=%p, cur=%p",
+                    name, prev, cur);
+            result = false;
+        }
+        prev = cur;
+        cur++;
+    }
+    if (b != reg.getBounds()) {
+        result = false;
+        LOGE("%s: invalid bounds [%d,%d,%d,%d] vs. [%d,%d,%d,%d]", name,
+                b.left, b.top, b.right, b.bottom,
+                reg.getBounds().left, reg.getBounds().top, 
+                reg.getBounds().right, reg.getBounds().bottom);
+    }
+    if (result == false) {
+        reg.dump(name);
+    }
+    return result;
 }
 
-int Region::iterator::iterate(Rect* rect)
+void Region::boolean_operation(int op, Region& dst,
+        const Region& lhs,
+        const Region& rhs, int dx, int dy)
 {
-    if (mIt.done())
-        return 0;
-    const SkIRect& r(mIt.rect());
-    rect->left  = r.fLeft;
-    rect->top   = r.fTop;
-    rect->right = r.fRight;
-    rect->bottom= r.fBottom;
-    mIt.next();
-    return 1;
+    size_t lhs_count;
+    Rect const * const lhs_rects = lhs.getArray(&lhs_count);
+
+    size_t rhs_count;
+    Rect const * const rhs_rects = rhs.getArray(&rhs_count);
+
+    region_operator<Rect>::region lhs_region(lhs_rects, lhs_count);
+    region_operator<Rect>::region rhs_region(rhs_rects, rhs_count, dx, dy);
+    region_operator<Rect> operation(op, lhs_region, rhs_region);
+    { // scope for rasterizer (dtor has side effects)
+        rasterizer r(dst);
+        operation(r);
+    }
+
+#if VALIDATE_REGIONS
+    validate(lhs, "boolean_operation: lhs");
+    validate(rhs, "boolean_operation: rhs");
+    validate(dst, "boolean_operation: dst");
+#endif
+
+#if VALIDATE_WITH_CORECG
+    SkRegion sk_lhs;
+    SkRegion sk_rhs;
+    SkRegion sk_dst;
+    
+    for (size_t i=0 ; i<lhs_count ; i++)
+        sk_lhs.op(
+                lhs_rects[i].left   + dx,
+                lhs_rects[i].top    + dy,
+                lhs_rects[i].right  + dx,
+                lhs_rects[i].bottom + dy,
+                SkRegion::kUnion_Op);
+    
+    for (size_t i=0 ; i<rhs_count ; i++)
+        sk_rhs.op(
+                rhs_rects[i].left   + dx,
+                rhs_rects[i].top    + dy,
+                rhs_rects[i].right  + dx,
+                rhs_rects[i].bottom + dy,
+                SkRegion::kUnion_Op);
+ 
+    const char* name = "---";
+    SkRegion::Op sk_op;
+    switch (op) {
+        case op_or: sk_op = SkRegion::kUnion_Op; name="OR"; break;
+        case op_and: sk_op = SkRegion::kIntersect_Op; name="AND"; break;
+        case op_nand: sk_op = SkRegion::kDifference_Op; name="NAND"; break;
+    }
+    sk_dst.op(sk_lhs, sk_rhs, sk_op);
+
+    if (sk_dst.isEmpty() && dst.isEmpty())
+        return;
+    
+    bool same = true;
+    Region::const_iterator head = dst.begin();
+    Region::const_iterator const tail = dst.end();
+    SkRegion::Iterator it(sk_dst);
+    while (!it.done()) {
+        if (head != tail) {
+            if (
+                    head->left != it.rect().fLeft ||     
+                    head->top != it.rect().fTop ||     
+                    head->right != it.rect().fRight ||     
+                    head->bottom != it.rect().fBottom
+            ) {
+                same = false;
+                break;
+            }
+        } else {
+            same = false;
+            break;
+        }
+        head++;
+        it.next();
+    }
+    
+    if (head != tail) {
+        same = false;
+    }
+    
+    if(!same) {
+        LOGD("---\nregion boolean %s failed", name);
+        lhs.dump("lhs");
+        rhs.dump("rhs");
+        dst.dump("dst");
+        LOGD("should be");
+        SkRegion::Iterator it(sk_dst);
+        while (!it.done()) {
+            LOGD("    [%3d, %3d, %3d, %3d]",
+                it.rect().fLeft,
+                it.rect().fTop,
+                it.rect().fRight,
+                it.rect().fBottom);
+            it.next();
+        }
+    }
+#endif
+}
+
+void Region::boolean_operation(int op, Region& dst,
+        const Region& lhs,
+        const Rect& rhs, int dx, int dy)
+{
+#if VALIDATE_WITH_CORECG || VALIDATE_REGIONS
+    boolean_operation(op, dst, lhs, Region(rhs), dx, dy);
+#else
+    size_t lhs_count;
+    Rect const * const lhs_rects = lhs.getArray(&lhs_count);
+
+    region_operator<Rect>::region lhs_region(lhs_rects, lhs_count);
+    region_operator<Rect>::region rhs_region(&rhs, 1, dx, dy);
+    region_operator<Rect> operation(op, lhs_region, rhs_region);
+    { // scope for rasterizer (dtor has side effects)
+        rasterizer r(dst);
+        operation(r);
+    }
+
+#endif
+}
+
+void Region::boolean_operation(int op, Region& dst,
+        const Region& lhs, const Region& rhs)
+{
+    boolean_operation(op, dst, lhs, rhs, 0, 0);
+}
+
+void Region::boolean_operation(int op, Region& dst,
+        const Region& lhs, const Rect& rhs)
+{
+    boolean_operation(op, dst, lhs, rhs, 0, 0);
+}
+
+void Region::translate(Region& reg, int dx, int dy)
+{
+    if (!reg.isEmpty()) {
+#if VALIDATE_REGIONS
+        validate(reg, "translate (before)");
+#endif
+        reg.mBounds.translate(dx, dy);
+        size_t count = reg.mStorage.size();
+        Rect* rects = reg.mStorage.editArray();
+        while (count) {
+            rects->translate(dx, dy);
+            rects++;
+            count--;
+        }
+#if VALIDATE_REGIONS
+        validate(reg, "translate (after)");
+#endif
+    }
+}
+
+void Region::translate(Region& dst, const Region& reg, int dx, int dy)
+{
+    dst = reg;
+    translate(dst, dx, dy);
 }
 
 // ----------------------------------------------------------------------------
 
-// we write a 4byte size ahead of the actual region, so we know how much we'll need for reading
-
 status_t Region::write(Parcel& parcel) const
 {
-    int32_t size = mRegion.flatten(NULL);
-    parcel.writeInt32(size);
-    mRegion.flatten(parcel.writeInplace(size));
+#if VALIDATE_REGIONS
+    validate(*this, "write(Parcel)");
+#endif
+    status_t err;
+    const size_t count = mStorage.size();
+    const size_t sizeNeeded = sizeof(int32_t) + (1+count)*sizeof(Rect);
+    void* buffer = parcel.writeInplace(sizeNeeded);
+    if (!buffer) return NO_MEMORY;
+    ssize_t written = Region::write(buffer, sizeNeeded);
+    if (written < 0) return status_t(written);
     return NO_ERROR;
 }
 
 status_t Region::read(const Parcel& parcel)
 {
-    size_t size = parcel.readInt32();
-    mRegion.unflatten(parcel.readInplace(size));
+    void const* buffer = parcel.readInplace(sizeof(int32_t));
+    if (!buffer) return NO_MEMORY;
+    const size_t count = *static_cast<int32_t const *>(buffer);
+    void const* dummy = parcel.readInplace((1+count)*sizeof(Rect));
+    if (!dummy) return NO_MEMORY;
+    const size_t sizeNeeded = sizeof(int32_t) + (1+count)*sizeof(Rect);
+    const ssize_t read = Region::read(buffer);
+    if (read < 0) return status_t(read);
+#if VALIDATE_REGIONS
+    validate(*this, "read(Parcel)");
+#endif
     return NO_ERROR;
 }
 
 ssize_t Region::write(void* buffer, size_t size) const
 {
-    size_t sizeNeeded = mRegion.flatten(NULL);
+#if VALIDATE_REGIONS
+    validate(*this, "write(buffer)");
+#endif
+    const size_t count = mStorage.size();
+    const size_t sizeNeeded = sizeof(int32_t) + (1+count)*sizeof(Rect);
     if (sizeNeeded > size) return NO_MEMORY;
-    return mRegion.flatten(buffer);
+    int32_t* const p = static_cast<int32_t*>(buffer); 
+    *p = count;
+    memcpy(p+1, &mBounds, sizeof(Rect));
+    if (count) {
+        memcpy(p+5, mStorage.array(), count*sizeof(Rect));
+    }
+    return ssize_t(sizeNeeded);
 }
 
 ssize_t Region::read(const void* buffer)
 {
-    return mRegion.unflatten(buffer);
+    int32_t const* const p = static_cast<int32_t const*>(buffer); 
+    const size_t count = *p;
+    memcpy(&mBounds, p+1, sizeof(Rect));
+    mStorage.clear();
+    if (count) {
+        mStorage.insertAt(0, count);
+        memcpy(mStorage.editArray(), p+5, count*sizeof(Rect));
+    }
+#if VALIDATE_REGIONS
+    validate(*this, "read(buffer)");
+#endif
+    return ssize_t(sizeof(int32_t) + (1+count)*sizeof(Rect));
 }
 
 ssize_t Region::writeEmpty(void* buffer, size_t size)
 {
-    if (size < 4) return NO_MEMORY;
-    // this needs to stay in sync with SkRegion
-    *static_cast<int32_t*>(buffer) = -1;
-    return 4;
+    const size_t sizeNeeded = sizeof(int32_t) + sizeof(Rect);
+    if (sizeNeeded > size) return NO_MEMORY;
+    int32_t* const p = static_cast<int32_t*>(buffer); 
+    memset(p, 0, sizeNeeded);
+    return ssize_t(sizeNeeded);
 }
 
 bool Region::isEmpty(void* buffer)
 {
-    // this needs to stay in sync with SkRegion
-    return *static_cast<int32_t*>(buffer) == -1;
+    int32_t const* const p = static_cast<int32_t const*>(buffer); 
+    Rect const* const b = reinterpret_cast<Rect const *>(p+1);
+    return b->isEmpty();
 }
 
-size_t Region::rects(Vector<Rect>& rectList) const
+// ----------------------------------------------------------------------------
+
+Region::const_iterator Region::begin() const {
+    return isRect() ? &mBounds : mStorage.array();
+}
+
+Region::const_iterator Region::end() const {
+    return isRect() ? ((&mBounds) + 1) : (mStorage.array() + mStorage.size());
+}
+
+Rect const* Region::getArray(size_t* count) const {
+    const_iterator const b(begin());
+    const_iterator const e(end());
+    if (count) *count = e-b;
+    return b;
+}
+
+size_t Region::getRects(Vector<Rect>& rectList) const
 {
-    rectList.clear();
-    if (!isEmpty()) {
-        SkRegion::Iterator iterator(mRegion);
-        while( !iterator.done() ) {
-            const SkIRect& ir(iterator.rect());
-            rectList.push(Rect(ir.fLeft, ir.fTop, ir.fRight, ir.fBottom));
-            iterator.next();
-        }
+    rectList = mStorage;
+    if (rectList.isEmpty()) {
+        rectList.clear();
+        rectList.add(mBounds);
     }
     return rectList.size();
 }
 
+// ----------------------------------------------------------------------------
+
 void Region::dump(String8& out, const char* what, uint32_t flags) const
 {
     (void)flags;
-    Vector<Rect> r;
-    rects(r);
-    
+    const_iterator head = begin();
+    const_iterator const tail = end();
+
     size_t SIZE = 256;
     char buffer[SIZE];
-    
-    snprintf(buffer, SIZE, "  Region %s (this=%p, count=%d)\n", what, this, r.size());
+
+    snprintf(buffer, SIZE, "  Region %s (this=%p, count=%d)\n",
+            what, this, tail-head);
     out.append(buffer);
-    for (size_t i=0 ; i<r.size() ; i++) {
+    while (head != tail) {
         snprintf(buffer, SIZE, "    [%3d, %3d, %3d, %3d]\n",
-            r[i].left, r[i].top,r[i].right,r[i].bottom);
+                head->left, head->top, head->right, head->bottom);
         out.append(buffer);
+        head++;
     }
 }
 
 void Region::dump(const char* what, uint32_t flags) const
 {
     (void)flags;
-    Vector<Rect> r;
-    rects(r);
-    LOGD("  Region %s (this=%p, count=%d)\n", what, this, r.size());
-    for (size_t i=0 ; i<r.size() ; i++) {
+    const_iterator head = begin();
+    const_iterator const tail = end();
+    LOGD("  Region %s (this=%p, count=%d)\n", what, this, tail-head);
+    while (head != tail) {
         LOGD("    [%3d, %3d, %3d, %3d]\n",
-            r[i].left, r[i].top,r[i].right,r[i].bottom);
+                head->left, head->top, head->right, head->bottom);
+        head++;
     }
 }
 
diff --git a/libs/ui/Surface.cpp b/libs/ui/Surface.cpp
index 6437619..6db30c3 100644
--- a/libs/ui/Surface.cpp
+++ b/libs/ui/Surface.cpp
@@ -125,15 +125,17 @@
     uint8_t* dst_bits;
     dst->lock(GRALLOC_USAGE_SW_WRITE_OFTEN, reg.bounds(), (void**)&dst_bits);
     
-    Region::iterator iterator(reg);
-    if (iterator) {
+    size_t c;
+    Rect const* const rects = reg.getArray(&c);
+    
+    if (c) {
         // NOTE: dst and src must be the same format
-        Rect r;
         const size_t bpp = bytesPerPixel(src->format);
         const size_t dbpr = dst->stride * bpp;
         const size_t sbpr = src->stride * bpp;
 
-        while (iterator.iterate(&r)) {
+        for (size_t i=0 ; i<c ; i++) {
+            const Rect& r = rects[i];
             ssize_t h = r.height();
             if (h <= 0) continue;
             size_t size = r.width() * bpp;
diff --git a/libs/ui/tests/Android.mk b/libs/ui/tests/Android.mk
new file mode 100644
index 0000000..6cc4a5a
--- /dev/null
+++ b/libs/ui/tests/Android.mk
@@ -0,0 +1,16 @@
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES:= \
+	region.cpp
+
+LOCAL_SHARED_LIBRARIES := \
+	libcutils \
+	libutils \
+    libui
+
+LOCAL_MODULE:= test-region
+
+LOCAL_MODULE_TAGS := tests
+
+include $(BUILD_EXECUTABLE)
diff --git a/libs/ui/tests/region.cpp b/libs/ui/tests/region.cpp
new file mode 100644
index 0000000..0deb2ba
--- /dev/null
+++ b/libs/ui/tests/region.cpp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2009 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 "Region"
+
+#include <stdio.h>
+#include <utils/Debug.h>
+#include <ui/Rect.h>
+#include <ui/Region.h>
+
+using namespace android;
+
+int main()
+{
+    Region reg0( Rect(  0, 0,  100, 100 ) );
+    Region reg1 = reg0;
+    Region reg2, reg3;
+    
+    reg0.dump("reg0");
+    reg1.dump("reg1");
+
+    reg0 = reg0 | reg0.translate(150, 0);
+    reg0.dump("reg0");
+    reg1.dump("reg1");
+
+    reg0 = reg0 | reg0.translate(300, 0);
+    reg0.dump("reg0");
+    reg1.dump("reg1");
+
+    //reg2 = reg0 | reg0.translate(0, 100);
+    //reg0.dump("reg0");
+    //reg1.dump("reg1");
+    //reg2.dump("reg2");
+
+    //reg3 = reg0 | reg0.translate(0, 150);
+    //reg0.dump("reg0");
+    //reg1.dump("reg1");
+    //reg2.dump("reg2");
+    //reg3.dump("reg3");
+
+    LOGD("---");
+    reg2 = reg0 | reg0.translate(100, 0);
+    reg0.dump("reg0");
+    reg1.dump("reg1");
+    reg2.dump("reg2");
+    
+    return 0;
+}
+