gm/xfermodes2.cpp

   1 /*
   2  * Copyright 2013 Google Inc.
   3  *
   4  * Use of this source code is governed by a BSD-style license that can be
   5  * found in the LICENSE file.
   6  */
   7 #include "gm.h"
   8 #include "SkBitmap.h"
   9 #include "SkShader.h"
  10 #include "SkXfermode.h"
  11 #include "SkColorPriv.h"
  12
  13 namespace skiagm {
  14
  15 class Xfermodes2GM : public GM {
  16 public:
  17     Xfermodes2GM() {}
  18
  19 protected:
  20     SkString onShortName() override {
  21         return SkString("xfermodes2");
  22     }
  23
  24     SkISize onISize() override {
  25         return SkISize::Make(455, 475);
  26     }
  27
  28     void onDraw(SkCanvas* canvas) override {
  29         canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
  30
  31         const SkScalar w = SkIntToScalar(kSize);
  32         const SkScalar h = SkIntToScalar(kSize);
  33
  34         SkPaint labelP;
  35         labelP.setAntiAlias(true);
  36         sk_tool_utils::set_portable_typeface(&labelP);
  37         labelP.setTextAlign(SkPaint::kCenter_Align);
  38
  39         const int W = 6;
  40
  41         SkScalar x = 0, y = 0;
  42         for (size_t m = 0; m <= SkXfermode::kLastMode; m++) {
  43             SkBlendMode mode = static_cast<SkBlendMode>(m);
  44
  45             canvas->save();
  46
  47             canvas->translate(x, y);
  48             SkPaint p;
  49             p.setAntiAlias(false);
  50             p.setStyle(SkPaint::kFill_Style);
  51             p.setShader(fBG);
  52             SkRect r = SkRect::MakeWH(w, h);
  53             canvas->drawRect(r, p);
  54
  55             canvas->saveLayer(&r, nullptr);
  56
  57             p.setShader(fDst);
  58             canvas->drawRect(r, p);
  59             p.setShader(fSrc);
  60             p.setBlendMode(mode);
  61             canvas->drawRect(r, p);
  62
  63             canvas->restore();
  64
  65             r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
  66             p.setStyle(SkPaint::kStroke_Style);
  67             p.setShader(nullptr);
  68             p.setBlendMode(SkBlendMode::kSrcOver);
  69             canvas->drawRect(r, p);
  70
  71             canvas->restore();
  72
  73 #if 1
  74             canvas->drawText(SkXfermode::ModeName(mode), strlen(SkXfermode::ModeName(mode)),
  75                              x + w/2, y - labelP.getTextSize()/2, labelP);
  76 #endif
  77             x += w + SkIntToScalar(10);
  78             if ((m % W) == W - 1) {
  79                 x = 0;
  80                 y += h + SkIntToScalar(30);
  81             }
  82         }
  83     }
  84
  85 private:
  86     void onOnceBeforeDraw() override {
  87         const uint32_t kCheckData[] = {
  88             SkPackARGB32(0xFF, 0x42, 0x41, 0x42),
  89             SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
  90             SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
  91             SkPackARGB32(0xFF, 0x42, 0x41, 0x42)
  92         };
  93         SkBitmap bg;
  94         bg.allocN32Pixels(2, 2, true);
  95         memcpy(bg.getPixels(), kCheckData, sizeof(kCheckData));
  96
  97         SkMatrix lm;
  98         lm.setScale(SkIntToScalar(16), SkIntToScalar(16));
  99         fBG = SkShader::MakeBitmapShader(bg, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode,
 100                                          &lm);
 101
 102         SkBitmap srcBmp;
 103         srcBmp.allocN32Pixels(kSize, kSize);
 104         SkPMColor* pixels = reinterpret_cast<SkPMColor*>(srcBmp.getPixels());
 105
 106         for (int y = 0; y < kSize; ++y) {
 107             int c = y * (1 << kShift);
 108             SkPMColor rowColor = SkPackARGB32(c, c, 0, c/2);
 109             for (int x = 0; x < kSize; ++x) {
 110                 pixels[kSize * y + x] = rowColor;
 111             }
 112         }
 113         fSrc = SkShader::MakeBitmapShader(srcBmp, SkShader::kClamp_TileMode,
 114                                           SkShader::kClamp_TileMode);
 115         SkBitmap dstBmp;
 116         dstBmp.allocN32Pixels(kSize, kSize);
 117         pixels = reinterpret_cast<SkPMColor*>(dstBmp.getPixels());
 118
 119         for (int x = 0; x < kSize; ++x) {
 120             int c = x * (1 << kShift);
 121             SkPMColor colColor = SkPackARGB32(c, 0, c, c/2);
 122             for (int y = 0; y < kSize; ++y) {
 123                 pixels[kSize * y + x] = colColor;
 124             }
 125         }
 126         fDst = SkShader::MakeBitmapShader(dstBmp, SkShader::kClamp_TileMode,
 127                                           SkShader::kClamp_TileMode);
 128     }
 129
 130     enum {
 131         kShift = 2,
 132         kSize = 256 >> kShift,
 133     };
 134
 135     sk_sp<SkShader> fBG;
 136     sk_sp<SkShader> fSrc;
 137     sk_sp<SkShader> fDst;
 138
 139     typedef GM INHERITED;
 140 };
 141
 142 //////////////////////////////////////////////////////////////////////////////
 143
 144 static GM* MyFactory(void*) { return new Xfermodes2GM; }
 145 static GMRegistry reg(MyFactory);
 146
 147 }