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/gm.h"
  #include "include/core/SkBitmap.h"
  #include "include/core/SkCanvas.h"
  #include "include/core/SkColor.h"
  #include "include/core/SkMatrix.h"
  #include "include/core/SkPaint.h"
  #include "include/core/SkScalar.h"
  #include "include/core/SkShader.h"
  #include "include/core/SkSize.h"
  #include "include/core/SkString.h"
  #include "include/core/SkTileMode.h"
  
  /*
   *  Want to ensure that our bitmap sampler (in bitmap shader) keeps plenty of
   *  precision when scaling very large images (where the dx might get very small.
   */
  
  #define W   257
  #define H   161
  
  class GiantBitmapGM : public skiagm::GM {
      SkBitmap* fBM;
      SkTileMode fMode;
      bool fDoFilter;
      bool fDoRotate;
  
      const SkBitmap& getBitmap() {
          if (nullptr == fBM) {
              fBM = new SkBitmap;
              fBM->allocN32Pixels(W, H);
              fBM->eraseColor(SK_ColorWHITE);
  
              const SkColor colors[] = {
                  SK_ColorBLUE, SK_ColorRED, SK_ColorBLACK, SK_ColorGREEN
              };
  
              SkCanvas canvas(*fBM);
              SkPaint paint;
              paint.setAntiAlias(true);
              paint.setStrokeWidth(SkIntToScalar(20));
  
  #if 0
              for (int y = -H*2; y < H; y += 50) {
                  SkScalar yy = SkIntToScalar(y);
                  paint.setColor(colors[y/50 & 0x3]);
                  canvas.drawLine(0, yy, SkIntToScalar(W), yy + SkIntToScalar(W),
                                  paint);
              }
  #else
              for (int x = -W; x < W; x += 60) {
                  paint.setColor(colors[x/60 & 0x3]);
  
                  SkScalar xx = SkIntToScalar(x);
                  canvas.drawLine(xx, 0, xx, SkIntToScalar(H),
                                  paint);
              }
  #endif
          }
          return *fBM;
      }
  
  public:
      GiantBitmapGM(SkTileMode mode, bool doFilter, bool doRotate) : fBM(nullptr) {
          fMode = mode;
          fDoFilter = doFilter;
          fDoRotate = doRotate;
      }
  
      ~GiantBitmapGM() override { delete fBM; }
  
  protected:
  
      SkString onShortName() override {
          SkString str("giantbitmap_");
          switch (fMode) {
              case SkTileMode::kClamp:
                  str.append("clamp");
                  break;
              case SkTileMode::kRepeat:
                  str.append("repeat");
                  break;
              case SkTileMode::kMirror:
                  str.append("mirror");
                  break;
              case SkTileMode::kDecal:
                  str.append("decal");
                  break;
              default:
                  break;
          }
          str.append(fDoFilter ? "_bilerp" : "_point");
          str.append(fDoRotate ? "_rotate" : "_scale");
          return str;
      }
  
      SkISize onISize() override { return SkISize::Make(640, 480); }
  
      void onDraw(SkCanvas* canvas) override {
          SkPaint paint;
  
          SkMatrix m;
          if (fDoRotate) {
              m.setSkew(SK_Scalar1, 0, 0, 0);
          } else {
              SkScalar scale = 11*SK_Scalar1/12;
              m.setScale(scale, scale);
          }
          paint.setShader(getBitmap().makeShader(
                                             fMode, fMode,
                                             SkSamplingOptions(fDoFilter ? SkFilterMode::kLinear
                                                                         : SkFilterMode::kNearest),
                                             m));
  
          canvas->translate(50, 50);
  
          canvas->drawPaint(paint);
      }
  
  private:
      using INHERITED = GM;
  };
  
  ///////////////////////////////////////////////////////////////////////////////
  
  DEF_GM( return new GiantBitmapGM(SkTileMode::kClamp, false, false); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kRepeat, false, false); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kMirror, false, false); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kClamp, true, false); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kRepeat, true, false); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kMirror, true, false); )
  
  DEF_GM( return new GiantBitmapGM(SkTileMode::kClamp, false, true); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kRepeat, false, true); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kMirror, false, true); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kClamp, true, true); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kRepeat, true, true); )
  DEF_GM( return new GiantBitmapGM(SkTileMode::kMirror, true, true); )
  