diff --git a/samplecode/SamplePatch.cpp b/samplecode/SamplePatch.cpp
new file mode 100644
index 0000000..2e55db2
--- /dev/null
+++ b/samplecode/SamplePatch.cpp
@@ -0,0 +1,418 @@
+#include "SampleCode.h"
+#include "SkView.h"
+#include "SkCanvas.h"
+#include "SkGradientShader.h"
+#include "SkGraphics.h"
+#include "SkImageDecoder.h"
+#include "SkPath.h"
+#include "SkPorterDuff.h"
+#include "SkRandom.h"
+#include "SkRegion.h"
+#include "SkShader.h"
+#include "SkUtils.h"
+#include "SkXfermode.h"
+#include "SkShaderExtras.h"
+#include "SkColorPriv.h"
+#include "SkColorFilter.h"
+#include "SkTime.h"
+#include "SkTypeface.h"
+
+#include "SkImageRef.h"
+#include "SkOSFile.h"
+#include "SkStream.h"
+
+#include "SkGeometry.h" // private include :(
+
+static void drawtriangle(SkCanvas* canvas, const SkPaint& paint,
+                         const SkPoint pts[3]) {
+    SkPath path;
+    
+    path.moveTo(pts[0]);
+    path.lineTo(pts[1]);
+    path.lineTo(pts[2]);
+    
+    canvas->drawPath(path, paint);
+}
+
+static SkShader* make_shader0(SkIPoint* size) {
+    SkBitmap    bm;
+    
+//    SkImageDecoder::DecodeFile("/skimages/progressivejpg.jpg", &bm);
+    SkImageDecoder::DecodeFile("/skimages/beach.jpg", &bm);
+    size->set(bm.width(), bm.height());
+    return SkShader::CreateBitmapShader(bm, SkShader::kClamp_TileMode,
+                                        SkShader::kClamp_TileMode);
+}
+
+static SkShader* make_shader1(const SkIPoint& size) {
+    SkPoint pts[] = { 0, 0, SkIntToScalar(size.fX), SkIntToScalar(size.fY) };
+    SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorRED };
+    return SkGradientShader::CreateLinear(pts, colors, NULL,
+                    SK_ARRAY_COUNT(colors), SkShader::kMirror_TileMode, NULL);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+class Patch {
+public:
+    Patch() { bzero(fPts, sizeof(fPts)); }
+    ~Patch() {}
+    
+    void setPatch(const SkPoint pts[12]) {
+        memcpy(fPts, pts, 12 * sizeof(SkPoint));
+        fPts[12] = pts[0];  // the last shall be first
+    }
+    void setBounds(int w, int h) { fW = w; fH = h; }
+
+    void draw(SkCanvas*, const SkPaint&, int segsU, int segsV,
+              bool doTextures, bool doColors);
+    
+private:
+    SkPoint fPts[13];
+    int     fW, fH;
+};
+
+static void eval_patch_edge(const SkPoint cubic[], SkPoint samples[], int segs) {
+    SkScalar t = 0;
+    SkScalar dt = SK_Scalar1 / segs;
+
+    samples[0] = cubic[0];
+    for (int i = 1; i < segs; i++) {
+        t += dt;
+        SkEvalCubicAt(cubic, t, &samples[i], NULL, NULL);
+    }
+}
+
+static void eval_sheet(const SkPoint edge[], int nu, int nv, int iu, int iv,
+                       SkPoint* pt) {
+    const int TL = 0;
+    const int TR = nu;
+    const int BR = TR + nv;
+    const int BL = BR + nu;
+
+    SkScalar u = SkIntToScalar(iu) / nu;
+    SkScalar v = SkIntToScalar(iv) / nv;
+    
+    SkScalar uv = SkScalarMul(u, v);
+    SkScalar Uv = SkScalarMul(SK_Scalar1 - u, v);
+    SkScalar uV = SkScalarMul(u, SK_Scalar1 - v);
+    SkScalar UV = SkScalarMul(SK_Scalar1 - u, SK_Scalar1 - v);
+    
+    SkScalar x0 = SkScalarMul(UV, edge[TL].fX) + SkScalarMul(uV, edge[TR].fX) +
+                  SkScalarMul(Uv, edge[BL].fX) + SkScalarMul(uv, edge[BR].fX);
+    SkScalar y0 = SkScalarMul(UV, edge[TL].fY) + SkScalarMul(uV, edge[TR].fY) +
+                  SkScalarMul(Uv, edge[BL].fY) + SkScalarMul(uv, edge[BR].fY);
+
+    SkScalar x =    SkScalarMul(SK_Scalar1 - v, edge[TL+iu].fX) +
+                    SkScalarMul(u, edge[TR+iv].fX) +
+                    SkScalarMul(v, edge[BR+nu-iu].fX) +
+                    SkScalarMul(SK_Scalar1 - u, edge[BL+nv-iv].fX) - x0;
+    SkScalar y =    SkScalarMul(SK_Scalar1 - v, edge[TL+iu].fY) +
+                    SkScalarMul(u, edge[TR+iv].fY) +
+                    SkScalarMul(v, edge[BR+nu-iu].fY) +
+                    SkScalarMul(SK_Scalar1 - u, edge[BL+nv-iv].fY) - y0;
+    pt->set(x, y);
+}
+
+static int ScalarTo255(SkScalar v) {
+    int scale = SkScalarToFixed(v) >> 8;
+    if (scale < 0) {
+        scale = 0;
+    } else if (scale > 255) {
+        scale = 255;
+    }
+    return scale;
+}
+
+static SkColor make_color(SkScalar s, SkScalar t) {
+    int cs = ScalarTo255(s);
+    int ct = ScalarTo255(t);    
+    return SkColorSetARGB(0xFF, cs, 0, 0) + SkColorSetARGB(0, 0, ct, 0);
+}
+
+void Patch::draw(SkCanvas* canvas, const SkPaint& paint, int nu, int nv,
+                 bool doTextures, bool doColors) {
+    if (nu < 1 || nv < 1) {
+        return;
+    }
+
+    int i, npts = (nu + nv) * 2;
+    SkAutoSTMalloc<16, SkPoint> storage(npts + 1);
+    SkPoint* edge0 = storage.get();
+    SkPoint* edge1 = edge0 + nu;
+    SkPoint* edge2 = edge1 + nv;
+    SkPoint* edge3 = edge2 + nu;
+    
+    // evaluate the edge points
+    eval_patch_edge(fPts + 0, edge0, nu);
+    eval_patch_edge(fPts + 3, edge1, nv);
+    eval_patch_edge(fPts + 6, edge2, nu);
+    eval_patch_edge(fPts + 9, edge3, nv);
+    edge3[nv] = edge0[0];   // the last shall be first
+    
+    for (i = 0; i < npts; i++) {
+//        canvas->drawLine(edge0[i].fX, edge0[i].fY, edge0[i+1].fX, edge0[i+1].fY, paint);
+    }
+    
+    int row, vertCount = (nu + 1) * (nv + 1);
+    SkAutoTMalloc<SkPoint>  vertStorage(vertCount);
+    SkPoint* verts = vertStorage.get();
+    
+    // first row
+    memcpy(verts, edge0, (nu + 1) * sizeof(SkPoint));
+    // rows
+    SkPoint* r = verts;
+    for (row = 1; row < nv; row++) {
+        r += nu + 1;
+        r[0] = edge3[nv - row];
+        for (int col = 1; col < nu; col++) {
+            eval_sheet(edge0, nu, nv, col, row, &r[col]);
+        }
+        r[nu] = edge1[row];
+    }
+    // last row
+    SkPoint* last = verts + nv * (nu + 1);
+    for (i = 0; i <= nu; i++) {
+        last[i] = edge2[nu - i];
+    }
+    
+//    canvas->drawPoints(verts, vertCount, paint);
+    
+    int stripCount = (nu + 1) * 2;
+    SkAutoTMalloc<SkPoint>  stripStorage(stripCount * 2);
+    SkAutoTMalloc<SkColor>  colorStorage(stripCount);
+    SkPoint* strip = stripStorage.get();
+    SkPoint* tex = strip + stripCount;
+    SkColor* colors = colorStorage.get();
+    SkScalar t = 0;
+    const SkScalar ds = SK_Scalar1 * fW / nu;
+    const SkScalar dt = SK_Scalar1 * fH / nv;
+    r = verts;
+    for (row = 0; row < nv; row++) {
+        SkPoint* upper = r;
+        SkPoint* lower = r + nu + 1;
+        r = lower;
+        SkScalar s = 0;
+        for (i = 0; i <= nu; i++)  {
+            strip[i*2 + 0] = *upper++;
+            strip[i*2 + 1] = *lower++;
+            tex[i*2 + 0].set(s, t);
+            tex[i*2 + 1].set(s, t + dt);
+            colors[i*2 + 0] = make_color(s/fW, t/fH);
+            colors[i*2 + 1] = make_color(s/fW, (t + dt)/fH);
+            s += ds;
+        }
+        t += dt;
+        canvas->drawVertices(SkCanvas::kTriangleStrip_VertexMode, stripCount,
+                             strip, doTextures ? tex : NULL,
+                             doColors ? colors : NULL, NULL,
+                             NULL, 0, paint);
+    }
+}
+
+static void drawpatches(SkCanvas* canvas, const SkPaint& paint, int nu, int nv,
+                        Patch* patch) {
+
+    SkAutoCanvasRestore ar(canvas, true);
+
+    patch->draw(canvas, paint, 10, 10, false, false);
+    canvas->translate(SkIntToScalar(300), 0);
+    patch->draw(canvas, paint, 10, 10, true, false);
+    canvas->translate(SkIntToScalar(300), 0);
+    patch->draw(canvas, paint, 10, 10, false, true);
+    canvas->translate(SkIntToScalar(300), 0);
+    patch->draw(canvas, paint, 10, 10, true, true);
+}
+
+class PatchView : public SkView {
+    SkShader*   fShader0;
+    SkShader*   fShader1;
+    SkIPoint    fSize0, fSize1;
+    SkPoint     fPts[12];
+    
+public:    
+	PatchView() {
+        fShader0 = make_shader0(&fSize0);
+        fSize1 = fSize0;
+        if (fSize0.fX == 0 || fSize0.fY == 0) {
+            fSize1.set(2, 2);
+        }
+        fShader1 = make_shader1(fSize1);
+
+        const SkScalar S = SkIntToScalar(90);
+        const SkScalar T = SkIntToScalar(64);
+        fPts[0].set(S*1, T);
+        fPts[1].set(S*2, T);
+        fPts[2].set(S*3, T);
+        fPts[3].set(S*4, T);
+        fPts[4].set(S*4, T*2);
+        fPts[5].set(S*4, T*3);
+        fPts[6].set(S*4, T*4);
+        fPts[7].set(S*3, T*4);
+        fPts[8].set(S*2, T*4);
+        fPts[9].set(S*1, T*4);
+        fPts[10].set(S*1, T*3);
+        fPts[11].set(S*1, T*2);
+    }
+    
+    virtual ~PatchView() {
+        fShader0->safeUnref();
+        fShader1->safeUnref();
+    }
+    
+protected:
+    // overrides from SkEventSink
+    virtual bool onQuery(SkEvent* evt)  {
+        if (SampleCode::TitleQ(*evt))
+        {
+            SkString str("Patch");
+            SampleCode::TitleR(evt, str.c_str());
+            return true;
+        }
+        return this->INHERITED::onQuery(evt);
+    }
+    
+    void drawBG(SkCanvas* canvas) {
+        canvas->drawColor(SK_ColorGRAY);
+    }
+    
+    virtual void onDraw(SkCanvas* canvas) {
+        this->drawBG(canvas);
+        
+        SkPaint paint;
+        paint.setDither(true);
+        paint.setFilterBitmap(true);
+
+        if (false) {
+            SkPath p;
+            p.moveTo(0, 0);
+            p.lineTo(SkIntToScalar(30000), SkIntToScalar(30000));
+            paint.setStyle(SkPaint::kStroke_Style);
+            paint.setStrokeWidth(SkIntToScalar(4));
+            paint.setAntiAlias(true);
+            canvas->scale(SkIntToScalar(3), SkIntToScalar(3));
+            canvas->drawPath(p, paint);
+            return;
+        }
+        
+        if (false) {
+            for (int dy = -1; dy <= 2; dy++) {
+                canvas->save();
+                if (dy == 2) {
+                    canvas->translate(0, SK_Scalar1/2);
+                } else {
+                    canvas->translate(0, SkIntToScalar(dy)/100);
+                }
+            
+                SkBitmap bm;
+                bm.setConfig(SkBitmap::kARGB_8888_Config, 20, 20);
+                bm.allocPixels();
+                SkCanvas c(bm);
+                SkRect r = { 0, 0, 20*SK_Scalar1, SK_Scalar1 };
+                for (int y = 0; y < 20; y++) {
+                    SkPaint p;
+                    p.setARGB(0xFF, y*5&0xFF, y*13&0xFF, y*29&0xFF);
+                    c.drawRect(r, p);
+                    r.offset(0, SK_Scalar1);
+                }
+                SkIRect src;
+                SkRect  dst;
+                
+                static const int srcPts[] = {
+                 //   2, 0, 15, 2,
+                    2, 2, 15, 16,
+                    17, 2, 2, 16,
+                    19, 2, 1, 16,
+                //    2, 18, 15, 2
+                };
+                static const double dstPts[] = {
+                //    7, 262 15, 24.5,
+                    7, 286.5, 15, 16,
+                    22, 286.5, 5, 16,
+                    27, 286.5, 1, 16,
+                 //   7, 302.5, 15, 24.5
+                };
+                
+                SkPaint p;
+//                p.setFilterBitmap(true);
+                const int* s = srcPts;
+                const double* d = dstPts;
+                for (int i = 0; i < 3; i++) {
+                    src.set(s[0], s[1], s[0]+s[2], s[1]+s[3]);
+                    dst.set(SkDoubleToScalar(d[0]),
+                            SkDoubleToScalar(d[1]),
+                            SkDoubleToScalar(d[0]+d[2]),
+                            SkDoubleToScalar(d[1]+d[3]));
+                    canvas->drawBitmapRect(bm, &src, dst, &p);
+                    canvas->translate(SkDoubleToScalar(1), 0);
+                    s += 4;
+                    d += 4;
+                }
+                canvas->restore();
+                canvas->translate(SkIntToScalar(32), 0);
+            }
+            return;
+        }
+        
+        Patch   patch;
+        
+        paint.setShader(fShader0);
+        if (fSize0.fX == 0) {
+            fSize0.fX = 1;
+        }
+        if (fSize0.fY == 0) {
+            fSize0.fY = 1;
+        }
+        patch.setBounds(fSize0.fX, fSize0.fY);
+        
+        patch.setPatch(fPts);        
+        drawpatches(canvas, paint, 10, 10, &patch);
+        
+        paint.setShader(NULL);
+        paint.setAntiAlias(true);
+        paint.setStrokeWidth(SkIntToScalar(5));
+        canvas->drawPoints(SkCanvas::kPoints_PointMode, SK_ARRAY_COUNT(fPts),
+                           fPts, paint);
+        
+        canvas->translate(0, SkIntToScalar(300));
+        
+        paint.setAntiAlias(false);
+        paint.setShader(fShader1);
+        patch.setBounds(fSize1.fX, fSize1.fY);
+        drawpatches(canvas, paint, 10, 10, &patch);
+    }
+    
+    class PtClick : public Click {
+    public:
+        int fIndex;
+        PtClick(SkView* view, int index) : Click(view), fIndex(index) {}
+    };
+    
+    static bool hittest(const SkPoint& pt, SkScalar x, SkScalar y) {
+        return SkPoint::Length(pt.fX - x, pt.fY - y) < SkIntToScalar(5);
+    }
+    
+    virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) {
+        for (int i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
+            if (hittest(fPts[i], x, y)) {
+                return new PtClick(this, i);
+            }
+        }
+        return this->INHERITED::onFindClickHandler(x, y);
+    }
+    
+    virtual bool onClick(Click* click) {
+        fPts[((PtClick*)click)->fIndex].set(click->fCurr.fX, click->fCurr.fY);
+        this->inval(NULL);
+        return true;
+    }
+    
+private:
+    typedef SkView INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+static SkView* MyFactory() { return new PatchView; }
+static SkViewRegister reg(MyFactory);
+