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 "gm.h"
  #include "SkPath.h"
  #include "SkRegion.h"
  #include "SkShader.h"
  #include "SkUtils.h"
  #include "SkColorPriv.h"
  #include "SkColorFilter.h"
  #include "SkTypeface.h"
  
  // effects
  #include "SkGradientShader.h"
  #include "SkUnitMappers.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, SkPaint::FilterLevel filter_level,
                    SkShader::TileMode tmx, SkShader::TileMode tmy) {
      SkShader* shader = SkShader::CreateBitmapShader(bm, tmx, tmy);
      paint->setShader(shader)->unref();
      paint->setFilterLevel(filter_level);
  }
  
  static const SkColorType gColorTypes[] = {
      kPMColor_SkColorType,
      kRGB_565_SkColorType,
  };
  
  class ScaledTilingGM : public skiagm::GM {
      SkBlurDrawLooper    fLooper;
  public:
      ScaledTilingGM(bool powerOfTwoSize)
              : fLooper(SkIntToScalar(1), SkIntToScalar(2), SkIntToScalar(2), 0x88000000)
              , fPowerOfTwoSize(powerOfTwoSize) {
      }
  
      SkBitmap    fTexture[SK_ARRAY_COUNT(gColorTypes)];
  
  protected:
  
      enum {
          kPOTSize = 4,
          kNPOTSize = 3,
      };
  
      SkString onShortName() {
          SkString name("scaled_tilemodes");
          if (!fPowerOfTwoSize) {
              name.append("_npot");
          }
          return name;
      }
  
      SkISize onISize() { return SkISize::Make(880, 760); }
  
      virtual void onOnceBeforeDraw() SK_OVERRIDE {
          int size = fPowerOfTwoSize ? kPOTSize : kNPOTSize;
          for (size_t i = 0; i < SK_ARRAY_COUNT(gColorTypes); i++) {
              makebm(&fTexture[i], gColorTypes[i], size, size);
          }
      }
  
      virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
  
          float scale = 32.f/kPOTSize;
  
          int size = fPowerOfTwoSize ? kPOTSize : kNPOTSize;
  
          SkRect r = { 0, 0, SkIntToScalar(size*2), SkIntToScalar(size*2) };
  
          static const char* gColorTypeNames[] = { "8888" , "565", "4444" };
  
          static const SkPaint::FilterLevel           gFilterLevels[] =
              { SkPaint::kNone_FilterLevel,
                SkPaint::kLow_FilterLevel,
                SkPaint::kMedium_FilterLevel,
                SkPaint::kHigh_FilterLevel };
          static const char*          gFilterNames[] = { "None", "Low", "Medium", "High" };
  
          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)/scale;
  
          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);
                  canvas->drawText(str.c_str(), str.size(), scale*(x + r.width()/2), y, p);
  
                  x += r.width() * 4 / 3;
              }
          }
  
          y = SkIntToScalar(40) / scale;
  
          for (size_t i = 0; i < SK_ARRAY_COUNT(gColorTypes); i++) {
              for (size_t j = 0; j < SK_ARRAY_COUNT(gFilterLevels); j++) {
                  x = SkIntToScalar(10)/scale;
                  for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {
                      for (size_t ky = 0; ky < SK_ARRAY_COUNT(gModes); ky++) {
                          SkPaint paint;
  #if 1 // Temporary change to regen bitmap before each draw. This may help tracking down an issue
        // on SGX where resizing NPOT textures to POT textures exhibits a driver bug.
                          if (!fPowerOfTwoSize) {
                              makebm(&fTexture[i], gColorTypes[i], size, size);
                          }
  #endif
                          setup(&paint, fTexture[i], gFilterLevels[j], gModes[kx], gModes[ky]);
                          paint.setDither(true);
  
                          canvas->save();
                          canvas->scale(scale,scale);
                          canvas->translate(x, y);
                          canvas->drawRect(r, paint);
                          canvas->restore();
  
                          x += r.width() * 4 / 3;
                      }
                  }
                  {
                      SkPaint p;
                      SkString str;
                      p.setAntiAlias(true);
                      p.setLooper(&fLooper);
                      str.printf("%s, %s", gColorTypeNames[i], gFilterNames[j]);
                      canvas->drawText(str.c_str(), str.size(), scale*x, scale*(y + r.height() * 2 / 3), p);
                  }
  
                  y += r.height() * 4 / 3;
              }
          }
      }
  
  private:
      bool fPowerOfTwoSize;
      typedef skiagm::GM INHERITED;
  };
  
  static const int gWidth = 32;
  static const int gHeight = 32;
  
  static SkShader* make_bm(SkShader::TileMode tx, SkShader::TileMode ty) {
      SkBitmap bm;
      makebm(&bm, kPMColor_SkColorType, gWidth, gHeight);
      return SkShader::CreateBitmapShader(bm, tx, ty);
  }
  
  static SkShader* make_grad(SkShader::TileMode tx, SkShader::TileMode ty) {
      SkPoint pts[] = { { 0, 0 }, { SkIntToScalar(gWidth), SkIntToScalar(gHeight)} };
      SkPoint center = { SkIntToScalar(gWidth)/2, SkIntToScalar(gHeight)/2 };
      SkScalar rad = SkIntToScalar(gWidth)/2;
      SkColor colors[] = { 0xFFFF0000, 0xFF0044FF };
  
      int index = (int)ty;
      switch (index % 3) {
          case 0:
              return SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors), tx);
          case 1:
              return SkGradientShader::CreateRadial(center, rad, colors, NULL, SK_ARRAY_COUNT(colors), tx);
          case 2:
              return SkGradientShader::CreateSweep(center.fX, center.fY, colors, NULL, SK_ARRAY_COUNT(colors));
      }
  
      return NULL;
  }
  
  typedef SkShader* (*ShaderProc)(SkShader::TileMode, SkShader::TileMode);
  
  class ScaledTiling2GM : public skiagm::GM {
      ShaderProc fProc;
      SkString   fName;
  public:
      ScaledTiling2GM(ShaderProc proc, const char name[]) : fProc(proc) {
          fName.printf("scaled_tilemode_%s", name);
      }
  
  protected:
      SkString onShortName() {
          return fName;
      }
  
      SkISize onISize() { return SkISize::Make(880, 560); }
  
      virtual void onDraw(SkCanvas* canvas) {
          canvas->scale(SkIntToScalar(3)/2, SkIntToScalar(3)/2);
  
          const SkScalar w = SkIntToScalar(gWidth);
          const SkScalar h = SkIntToScalar(gHeight);
          SkRect r = { -w, -h, w*2, h*2 };
  
          static const SkShader::TileMode gModes[] = {
              SkShader::kClamp_TileMode, SkShader::kRepeat_TileMode, SkShader::kMirror_TileMode
          };
          static const char* gModeNames[] = {
              "Clamp", "Repeat", "Mirror"
          };
  
          SkScalar y = SkIntToScalar(24);
          SkScalar x = SkIntToScalar(66);
  
          SkPaint p;
          p.setAntiAlias(true);
          p.setTextAlign(SkPaint::kCenter_Align);
  
          for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {
              SkString str(gModeNames[kx]);
              canvas->drawText(str.c_str(), str.size(), x + r.width()/2, y, p);
              x += r.width() * 4 / 3;
          }
  
          y += SkIntToScalar(16) + h;
          p.setTextAlign(SkPaint::kRight_Align);
  
          for (size_t ky = 0; ky < SK_ARRAY_COUNT(gModes); ky++) {
              x = SkIntToScalar(16) + w;
  
              SkString str(gModeNames[ky]);
              canvas->drawText(str.c_str(), str.size(), x, y + h/2, p);
  
              x += SkIntToScalar(50);
              for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {
                  SkPaint paint;
                  paint.setShader(fProc(gModes[kx], gModes[ky]))->unref();
  
                  canvas->save();
                  canvas->translate(x, y);
                  canvas->drawRect(r, paint);
                  canvas->restore();
  
                  x += r.width() * 4 / 3;
              }
              y += r.height() * 4 / 3;
          }
      }
  
  private:
      typedef skiagm::GM INHERITED;
  };
  
  //////////////////////////////////////////////////////////////////////////////
  
  DEF_GM( return new ScaledTilingGM(true); )
  DEF_GM( return new ScaledTilingGM(false); )
  DEF_GM( return new ScaledTiling2GM(make_bm, "bitmap"); )
  DEF_GM( return new ScaledTiling2GM(make_grad, "gradient"); )
  