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 "SkPaint.h"
  #include "SkPath.h"
  #include "SkRegion.h"
  #include "SkShader.h"
  #include "SkUtils.h"
  #include "SkColorPriv.h"
  #include "SkColorFilter.h"
  #include "SkPicture.h"
  #include "SkTypeface.h"
  
  // effects
  #include "SkGradientShader.h"
  #include "SkUnitMappers.h"
  #include "SkBlurMask.h"
  #include "SkBlurDrawLooper.h"
  
  static void makebm(SkBitmap* bm, SkColorType ct, int w, int h) {
      bm->allocPixels(SkImageInfo::Make(w, h, ct, kPremul_SkAlphaType));
      bm->eraseColor(SK_ColorTRANSPARENT);
  
      SkCanvas    canvas(*bm);
      SkPoint     pts[] = { { 0, 0 }, { SkIntToScalar(w), SkIntToScalar(h) } };
      SkColor     colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
      SkScalar    pos[] = { 0, SK_Scalar1/2, SK_Scalar1 };
      SkPaint     paint;
  
      SkUnitMapper*   um = NULL;
  
      um = new SkCosineMapper;
  //    um = new SkDiscreteMapper(12);
  
      SkAutoUnref au(um);
  
      paint.setDither(true);
      paint.setShader(SkGradientShader::CreateLinear(pts, colors, pos,
                  SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode, um))->unref();
      canvas.drawPaint(paint);
  }
  
  static void setup(SkPaint* paint, const SkBitmap& bm, bool filter,
                    SkShader::TileMode tmx, SkShader::TileMode tmy) {
      SkShader* shader = SkShader::CreateBitmapShader(bm, tmx, tmy);
      paint->setShader(shader)->unref();
      paint->setFilterLevel(filter ? SkPaint::kLow_FilterLevel : SkPaint::kNone_FilterLevel);
  }
  
  static const SkColorType gColorTypes[] = {
      kN32_SkColorType,
      kRGB_565_SkColorType,
  };
  static const int gWidth = 32;
  static const int gHeight = 32;
  
  class TilingView : public SampleView {
      SkAutoTUnref<SkPicture>        fTextPicture;
      SkAutoTUnref<SkBlurDrawLooper> fLooper;
  public:
      TilingView()
              : fLooper(SkBlurDrawLooper::Create(0x88000000,
                                                 SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(1)),
                                                 SkIntToScalar(2), SkIntToScalar(2))) {
          for (size_t i = 0; i < SK_ARRAY_COUNT(gColorTypes); i++) {
              makebm(&fTexture[i], gColorTypes[i], gWidth, gHeight);
          }
      }
  
      virtual ~TilingView() {
      }
  
      SkBitmap    fTexture[SK_ARRAY_COUNT(gColorTypes)];
  
  protected:
      // overrides from SkEventSink
      virtual bool onQuery(SkEvent* evt) {
          if (SampleCode::TitleQ(*evt)) {
              SampleCode::TitleR(evt, "Tiling");
              return true;
          }
          return this->INHERITED::onQuery(evt);
      }
  
      virtual void onDrawContent(SkCanvas* canvas) {
          SkRect r = { 0, 0, SkIntToScalar(gWidth*2), SkIntToScalar(gHeight*2) };
  
          static const char* gConfigNames[] = { "8888", "565", "4444" };
  
          static const bool           gFilters[] = { false, true };
          static const char*          gFilterNames[] = {     "point",                     "bilinear" };
  
          static const SkShader::TileMode gModes[] = { SkShader::kClamp_TileMode, SkShader::kRepeat_TileMode, SkShader::kMirror_TileMode };
          static const char*          gModeNames[] = {    "C",                    "R",                   "M" };
  
          SkScalar y = SkIntToScalar(24);
          SkScalar x = SkIntToScalar(10);
  
          SkPictureRecorder recorder;
          SkCanvas* textCanvas = NULL;
          if (NULL == fTextPicture) {
              textCanvas = recorder.beginRecording(1000, 1000);
          }
  
          if (NULL != textCanvas) {
              for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {
                  for (size_t ky = 0; ky < SK_ARRAY_COUNT(gModes); ky++) {
                      SkPaint p;
                      SkString str;
                      p.setAntiAlias(true);
                      p.setDither(true);
                      p.setLooper(fLooper);
                      str.printf("[%s,%s]", gModeNames[kx], gModeNames[ky]);
  
                      p.setTextAlign(SkPaint::kCenter_Align);
                      textCanvas->drawText(str.c_str(), str.size(), x + r.width()/2, y, p);
  
                      x += r.width() * 4 / 3;
                  }
              }
          }
  
          y += SkIntToScalar(16);
  
          for (size_t i = 0; i < SK_ARRAY_COUNT(gColorTypes); i++) {
              for (size_t j = 0; j < SK_ARRAY_COUNT(gFilters); j++) {
                  x = SkIntToScalar(10);
                  for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {
                      for (size_t ky = 0; ky < SK_ARRAY_COUNT(gModes); ky++) {
                          SkPaint paint;
                          setup(&paint, fTexture[i], gFilters[j], gModes[kx], gModes[ky]);
                          paint.setDither(true);
  
                          canvas->save();
                          canvas->translate(x, y);
                          canvas->drawRect(r, paint);
                          canvas->restore();
  
                          x += r.width() * 4 / 3;
                      }
                  }
                  if (NULL != textCanvas) {
                      SkPaint p;
                      SkString str;
                      p.setAntiAlias(true);
                      p.setLooper(fLooper);
                      str.printf("%s, %s", gConfigNames[i], gFilterNames[j]);
                      textCanvas->drawText(str.c_str(), str.size(), x, y + r.height() * 2 / 3, p);
                  }
  
                  y += r.height() * 4 / 3;
              }
          }
  
          if (NULL != textCanvas) {
              SkASSERT(NULL == fTextPicture);
              fTextPicture.reset(recorder.endRecording());
          }
  
          SkASSERT(NULL != fTextPicture);
          canvas->drawPicture(*fTextPicture);
      }
  
  private:
      typedef SampleView INHERITED;
  };
  
  //////////////////////////////////////////////////////////////////////////////
  
  static SkView* MyFactory() { return new TilingView; }
  static SkViewRegister reg(MyFactory);
  