text: 
  /*
   * Copyright 2011 Google Inc.
   *
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   */
  
  #include "SampleCode.h"
  #include "SkView.h"
  #include "SkCanvas.h"
  #include "SkAAClip.h"
  
  static void testop(const SkIRect& r0, const SkIRect& r1, SkRegion::Op op,
                     const SkIRect& expectedR) {
      SkAAClip c0, c1, c2;
      c0.setRect(r0);
      c1.setRect(r1);
      c2.op(c0, c1, op);
  
      SkDEBUGCODE(SkIRect r2 = c2.getBounds());
      SkASSERT(r2 == expectedR);
  }
  
  static const struct {
      SkIRect r0;
      SkIRect r1;
      SkRegion::Op op;
      SkIRect expectedR;
  } gRec[] = {
      {{ 1, 2, 9, 3 }, { -3, 2, 5, 11 }, SkRegion::kDifference_Op, { 5, 2, 9, 3 }},
      {{ 1, 10, 5, 13 }, { 1, 2, 5, 11 }, SkRegion::kDifference_Op, { 1, 11, 5, 13 }},
      {{ 1, 10, 5, 13 }, { 1, 2, 5, 11 }, SkRegion::kReverseDifference_Op, { 1, 2, 5, 10 }},
  };
  
  static void testop() {
      for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); ++i) {
          testop(gRec[i].r0, gRec[i].r1, gRec[i].op, gRec[i].expectedR);
      }
  }
  
  static void drawClip(SkCanvas* canvas, const SkAAClip& clip) {
      SkMask mask;
      SkBitmap bm;
  
      clip.copyToMask(&mask);
      SkAutoMaskFreeImage amfi(mask.fImage);
  
      bm.setConfig(SkBitmap::kA8_Config, mask.fBounds.width(),
                   mask.fBounds.height(), mask.fRowBytes);
      bm.setPixels(mask.fImage);
  
      SkPaint paint;
      canvas->drawBitmap(bm,
                         SK_Scalar1 * mask.fBounds.fLeft,
                         SK_Scalar1 * mask.fBounds.fTop,
                         &paint);
  }
  
  class AAClipView : public SampleView {
  public:
      AAClipView() {
          testop();
      }
  
  protected:
      // overrides from SkEventSink
      virtual bool onQuery(SkEvent* evt) {
          if (SampleCode::TitleQ(*evt)) {
              SampleCode::TitleR(evt, "AAClip");
              return true;
          }
          return this->INHERITED::onQuery(evt);
      }
  
      virtual void onDrawContent(SkCanvas* canvas) {
  #if 1
          SkAAClip aaclip;
          SkPath path;
          SkRect bounds;
  
          bounds.set(0, 0, 20, 20);
          bounds.inset(SK_ScalarHalf, SK_ScalarHalf);
  
  //        path.addRect(bounds);
  //        path.addOval(bounds);
          path.addRoundRect(bounds, 4, 4);
          aaclip.setPath(path);
          canvas->translate(30, 30);
          drawClip(canvas, aaclip);
  
          SkAAClip aaclip2;
          path.offset(10, 10);
          aaclip2.setPath(path);
          canvas->translate(30, 0);
          drawClip(canvas, aaclip2);
  
          SkAAClip aaclip3;
          aaclip3.op(aaclip, aaclip2, SkRegion::kIntersect_Op);
          canvas->translate(30, 0);
          drawClip(canvas, aaclip3);
  
  #endif
  
  #if 0
          SkRect r;
          r.set(0, 0, this->width(), this->height());
          r.inset(20, 20);
          canvas->clipRect(r);
  
          SkPath path;
          path.addRect(r);
          SkPaint paint;
          paint.setAntiAlias(true);
          paint.setColor(SK_ColorRED);
          canvas->drawPath(path, paint);
  #endif
      }
  
  private:
      typedef SkView INHERITED;
  };
  
  //////////////////////////////////////////////////////////////////////////////
  
  static SkView* MyFactory() { return new AAClipView; }
  static SkViewRegister reg(MyFactory);
  