add boundary patch utils
diff --git a/Android.mk b/Android.mk
index 3d03194..5c0961e 100644
--- a/Android.mk
+++ b/Android.mk
@@ -156,9 +156,11 @@
 	src/core/SkUnPreMultiply.cpp \
 	src/core/SkXfermode.cpp \
 	src/core/SkWriter32.cpp \
+	src/utils/SkBoundaryPatch.cpp \
 	src/utils/SkCamera.cpp \
 	src/utils/SkDumpCanvas.cpp \
 	src/utils/SkInterpolator.cpp \
+	src/utils/SkMeshUtils.cpp \
 	src/utils/SkNinePatch.cpp \
 	src/utils/SkProxyCanvas.cpp
 
diff --git a/include/utils/SkBoundaryPatch.h b/include/utils/SkBoundaryPatch.h
new file mode 100644
index 0000000..835fc3e
--- /dev/null
+++ b/include/utils/SkBoundaryPatch.h
@@ -0,0 +1,55 @@
+#ifndef SkBoundaryPatch_DEFINED
+#define SkBoundaryPatch_DEFINED
+
+#include "SkPoint.h"
+#include "SkRefCnt.h"
+
+class SkBoundary : public SkRefCnt {
+public:
+    // These must be 0, 1, 2, 3 for efficiency in the subclass implementations
+    enum Edge {
+        kTop    = 0,
+        kRight  = 1,
+        kBottom = 2,
+        kLeft   = 3
+    };
+    // Edge index goes clockwise around the boundary, beginning at the "top"
+    virtual SkPoint eval(Edge, SkScalar unitInterval) = 0;
+};
+
+class SkBoundaryPatch {
+public:
+    SkBoundaryPatch();
+    ~SkBoundaryPatch();
+
+    SkBoundary* getBoundary() const { return fBoundary; }
+    SkBoundary* setBoundary(SkBoundary*);
+
+    SkPoint eval(SkScalar unitU, SkScalar unitV);
+    bool evalPatch(SkPoint verts[], int rows, int cols);
+
+private:
+    SkBoundary* fBoundary;
+};
+
+////////////////////////////////////////////////////////////////////////
+
+class SkLineBoundary : public SkBoundary {
+public:
+    SkPoint fPts[4];
+    
+    // override
+    virtual SkPoint eval(Edge, SkScalar);
+};
+
+class SkCubicBoundary : public SkBoundary {
+public:
+    // the caller sets the first 12 entries. The 13th is used by the impl.
+    SkPoint fPts[13];
+    
+    // override
+    virtual SkPoint eval(Edge, SkScalar);
+};
+
+#endif
+
diff --git a/include/utils/SkMeshUtils.h b/include/utils/SkMeshUtils.h
new file mode 100644
index 0000000..1235485
--- /dev/null
+++ b/include/utils/SkMeshUtils.h
@@ -0,0 +1,43 @@
+#ifndef SkMeshUtils_DEFINED
+#define SkMeshUtils_DEFINED
+
+#include "SkPoint.h"
+#include "SkColor.h"
+
+class SkBitmap;
+class SkCanvas;
+class SkPaint;
+
+class SkMeshIndices {
+public:
+    SkMeshIndices();
+    ~SkMeshIndices();
+    
+    bool init(int texW, int texH, int rows, int cols) {
+        return this->init(NULL, NULL, texW, texH, rows, cols);
+    }
+
+    bool init(SkPoint tex[], uint16_t indices[],
+              int texW, int texH, int rows, int cols);
+
+    size_t          indexCount() const { return fIndexCount; }
+    const uint16_t* indices() const { return fIndices; }
+
+    size_t          texCount() const { return fTexCount; }
+    const SkPoint*  tex() const { return fTex; }
+
+private:
+    size_t      fIndexCount, fTexCount;
+    SkPoint*    fTex;
+    uint16_t*   fIndices;
+    void*       fStorage; // may be null
+};
+
+class SkMeshUtils {
+public:
+    static void Draw(SkCanvas*, const SkBitmap&, int rows, int cols,
+                     const SkPoint verts[], const SkColor colors[],
+                     const SkPaint& paint);
+};
+
+#endif
diff --git a/src/utils/SkBoundaryPatch.cpp b/src/utils/SkBoundaryPatch.cpp
new file mode 100644
index 0000000..cdbc877
--- /dev/null
+++ b/src/utils/SkBoundaryPatch.cpp
@@ -0,0 +1,73 @@
+#include "SkBoundaryPatch.h"
+
+SkBoundaryPatch::SkBoundaryPatch() : fBoundary(NULL) {}
+
+SkBoundaryPatch::~SkBoundaryPatch() {
+    SkSafeUnref(fBoundary);
+}
+
+SkBoundary* SkBoundaryPatch::setBoundary(SkBoundary* b) {
+    SkRefCnt_SafeAssign(fBoundary, b);
+    return b;
+}
+
+static SkPoint SkMakePoint(SkScalar x, SkScalar y) {
+    SkPoint pt;
+    pt.set(x, y);
+    return pt;
+}
+
+static SkPoint SkPointInterp(const SkPoint& a, const SkPoint& b, SkScalar t) {
+    return SkMakePoint(SkScalarInterp(a.fX, b.fX, t),
+                       SkScalarInterp(a.fY, b.fY, t));
+}
+
+SkPoint SkBoundaryPatch::eval(SkScalar unitU, SkScalar unitV) {
+    SkBoundary* b = fBoundary;
+    SkPoint u = SkPointInterp(b->eval(SkBoundary::kLeft, SK_Scalar1 - unitV),
+                              b->eval(SkBoundary::kRight, unitV),
+                              unitU);
+    SkPoint v = SkPointInterp(b->eval(SkBoundary::kTop, unitU),
+                              b->eval(SkBoundary::kBottom, SK_Scalar1 - unitU),
+                              unitV);
+    return SkMakePoint(SkScalarAve(u.fX, v.fX),
+                       SkScalarAve(u.fY, v.fY));
+}
+
+bool SkBoundaryPatch::evalPatch(SkPoint verts[], int rows, int cols) {
+    if (rows < 2 || cols < 2) {
+        return false;
+    }
+
+    const SkScalar invR = SkScalarInvert(SkIntToScalar(rows - 1));
+    const SkScalar invC = SkScalarInvert(SkIntToScalar(cols - 1));
+    
+    for (int y = 0; y < cols; y++) {
+        SkScalar yy = y * invC;
+        for (int x = 0; x < rows; x++) {
+            *verts++ = this->eval(x * invR, yy);
+        }
+    }
+    return true;
+}
+
+////////////////////////////////////////////////////////////////////////
+
+#include "SkGeometry.h"
+
+SkPoint SkLineBoundary::eval(Edge e, SkScalar t) {
+    SkASSERT((unsigned)e < 4);
+    return SkPointInterp(fPts[e], fPts[(e + 1) & 3], t);
+}
+
+SkPoint SkCubicBoundary::eval(Edge e, SkScalar t) {
+    SkASSERT((unsigned)e < 4);
+
+    // ensure our 4th cubic wraps to the start of the first
+    fPts[12] = fPts[0];
+
+    SkPoint loc;
+    SkEvalCubicAt(&fPts[e * 3], t, &loc, NULL, NULL);
+    return loc;
+}
+
diff --git a/src/utils/SkMeshUtils.cpp b/src/utils/SkMeshUtils.cpp
new file mode 100644
index 0000000..0385b99
--- /dev/null
+++ b/src/utils/SkMeshUtils.cpp
@@ -0,0 +1,96 @@
+#include "SkMeshUtils.h"
+#include "SkCanvas.h"
+#include "SkPaint.h"
+
+SkMeshIndices::SkMeshIndices() {
+    sk_bzero(this, sizeof(*this));
+}
+
+SkMeshIndices::~SkMeshIndices() {
+    sk_free(fStorage);
+}
+
+bool SkMeshIndices::init(SkPoint tex[], uint16_t indices[],
+                         int texW, int texH, int rows, int cols) {
+    if (rows < 2 || cols < 2) {
+        sk_free(fStorage);
+        fStorage = NULL;
+        fTex = NULL;
+        fIndices = NULL;
+        fTexCount = fIndexCount = 0;
+        return false;
+    }
+
+    sk_free(fStorage);
+    fStorage = NULL;
+
+    fTexCount = rows * cols;
+    rows -= 1;
+    cols -= 1;
+    fIndexCount = rows * cols * 6;
+
+    if (tex) {
+        fTex = tex;
+        fIndices = indices;
+    } else {
+        fStorage = sk_malloc_throw(fTexCount * sizeof(SkPoint) +
+                                   fIndexCount * sizeof(uint16_t));
+        fTex = (SkPoint*)fStorage;
+        fIndices = (uint16_t*)(fTex + fTexCount);
+    }
+
+    // compute the indices
+    {
+        uint16_t* idx = fIndices;
+        int index = 0;
+        for (int y = 0; y < cols; y++) {
+            for (int x = 0; x < rows; x++) {
+                *idx++ = index;
+                *idx++ = index + rows + 1;
+                *idx++ = index + 1;
+                
+                *idx++ = index + 1;
+                *idx++ = index + rows + 1;
+                *idx++ = index + rows + 2;
+                
+                index += 1;
+            }
+            index += 1;
+        }
+    }
+
+    // compute texture coordinates
+    {
+        SkPoint* tex = fTex;
+        const SkScalar dx = SkIntToScalar(texW) / rows;
+        const SkScalar dy = SkIntToScalar(texH) / cols;
+        for (int y = 0; y <= cols; y++) {
+            for (int x = 0; x <= rows; x++) {
+                tex->set(x*dx, y*dy);
+                tex += 1;
+            }
+        }
+    }
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+#include "SkShader.h"
+
+void SkMeshUtils::Draw(SkCanvas* canvas, const SkBitmap& bitmap,
+                       int rows, int cols, const SkPoint verts[],
+                       const SkColor colors[], const SkPaint& paint) {
+    SkMeshIndices idx;
+    
+    if (idx.init(bitmap.width(), bitmap.height(), rows, cols)) {
+        SkPaint p(paint);
+        p.setShader(SkShader::CreateBitmapShader(bitmap,
+                                         SkShader::kClamp_TileMode,
+                                         SkShader::kClamp_TileMode))->unref();
+        canvas->drawVertices(SkCanvas::kTriangles_VertexMode,
+                             rows * cols, verts, idx.tex(), colors, NULL,
+                             idx.indices(), idx.indexCount(), p);
+    }
+}
+