gm/xfermodes2.cpp

   1
   2 /*
   3  * Copyright 2013 Google Inc.
   4  *
   5  * Use of this source code is governed by a BSD-style license that can be
   6  * found in the LICENSE file.
   7  */
   8 #include "gm.h"
   9 #include "SkBitmap.h"
  10 #include "SkShader.h"
  11 #include "SkXfermode.h"
  12 #include "SkColorPriv.h"
  13
  14 namespace skiagm {
  15
  16 class Xfermodes2GM : public GM {
  17 public:
  18     Xfermodes2GM() {}
  19
  20 protected:
  21     SkString onShortName() override {
  22         return SkString("xfermodes2");
  23     }
  24
  25     SkISize onISize() override {
  26         return SkISize::Make(455, 475);
  27     }
  28
  29     void onDraw(SkCanvas* canvas) override {
  30         canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
  31
  32         const SkScalar w = SkIntToScalar(kSize);
  33         const SkScalar h = SkIntToScalar(kSize);
  34
  35         SkPaint labelP;
  36         labelP.setAntiAlias(true);
  37         sk_tool_utils::set_portable_typeface(&labelP);
  38         labelP.setTextAlign(SkPaint::kCenter_Align);
  39
  40         const int W = 6;
  41
  42         SkScalar x = 0, y = 0;
  43         for (size_t m = 0; m <= SkXfermode::kLastMode; m++) {
  44             SkXfermode::Mode mode = static_cast<SkXfermode::Mode>(m);
  45             SkXfermode* xm = SkXfermode::Create(mode);
  46             SkAutoUnref aur(xm);
  47
  48             canvas->save();
  49
  50             canvas->translate(x, y);
  51             SkPaint p;
  52             p.setAntiAlias(false);
  53             p.setStyle(SkPaint::kFill_Style);
  54             p.setShader(fBG);
  55             SkRect r = SkRect::MakeWH(w, h);
  56             canvas->drawRect(r, p);
  57
  58             canvas->saveLayer(&r, NULL);
  59
  60             p.setShader(fDst);
  61             canvas->drawRect(r, p);
  62             p.setShader(fSrc);
  63             p.setXfermode(xm);
  64             canvas->drawRect(r, p);
  65
  66             canvas->restore();
  67
  68             r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
  69             p.setStyle(SkPaint::kStroke_Style);
  70             p.setShader(NULL);
  71             p.setXfermode(NULL);
  72             canvas->drawRect(r, p);
  73
  74             canvas->restore();
  75
  76 #if 1
  77             canvas->drawText(SkXfermode::ModeName(mode), strlen(SkXfermode::ModeName(mode)),
  78                              x + w/2, y - labelP.getTextSize()/2, labelP);
  79 #endif
  80             x += w + SkIntToScalar(10);
  81             if ((m % W) == W - 1) {
  82                 x = 0;
  83                 y += h + SkIntToScalar(30);
  84             }
  85         }
  86     }
  87
  88 private:
  89     void onOnceBeforeDraw() override {
  90         static const uint32_t kCheckData[] = {
  91             SkPackARGB32(0xFF, 0x40, 0x40, 0x40),
  92             SkPackARGB32(0xFF, 0xD0, 0xD0, 0xD0),
  93             SkPackARGB32(0xFF, 0xD0, 0xD0, 0xD0),
  94             SkPackARGB32(0xFF, 0x40, 0x40, 0x40)
  95         };
  96         SkBitmap bg;
  97         bg.allocN32Pixels(2, 2, true);
  98         memcpy(bg.getPixels(), kCheckData, sizeof(kCheckData));
  99
 100         SkMatrix lm;
 101         lm.setScale(SkIntToScalar(16), SkIntToScalar(16));
 102         fBG.reset(SkShader::CreateBitmapShader(bg,
 103                                                SkShader::kRepeat_TileMode,
 104                                                SkShader::kRepeat_TileMode,
 105                                                &lm));
 106
 107         SkBitmap dstBmp;
 108         dstBmp.allocN32Pixels(kSize, kSize);
 109         SkPMColor* pixels = reinterpret_cast<SkPMColor*>(dstBmp.getPixels());
 110
 111         for (int y = 0; y < kSize; ++y) {
 112             int c = y * (1 << kShift);
 113             SkPMColor rowColor = SkPackARGB32(c, c, 0, c/2);
 114             for (int x = 0; x < kSize; ++x) {
 115                 pixels[kSize * y + x] = rowColor;
 116             }
 117         }
 118         fSrc.reset(SkShader::CreateBitmapShader(dstBmp,
 119                                                 SkShader::kClamp_TileMode,
 120                                                 SkShader::kClamp_TileMode));
 121         SkBitmap srcBmp;
 122         srcBmp.allocN32Pixels(kSize, kSize);
 123         pixels = reinterpret_cast<SkPMColor*>(srcBmp.getPixels());
 124
 125         for (int x = 0; x < kSize; ++x) {
 126             int c = x * (1 << kShift);
 127             SkPMColor colColor = SkPackARGB32(c, 0, c, c/2);
 128             for (int y = 0; y < kSize; ++y) {
 129                 pixels[kSize * y + x] = colColor;
 130             }
 131         }
 132         fDst.reset(SkShader::CreateBitmapShader(srcBmp,
 133                                                 SkShader::kClamp_TileMode,
 134                                                 SkShader::kClamp_TileMode));
 135     }
 136
 137     enum {
 138         kShift = 2,
 139         kSize = 256 >> kShift,
 140     };
 141
 142     SkAutoTUnref<SkShader> fBG;
 143     SkAutoTUnref<SkShader> fSrc;
 144     SkAutoTUnref<SkShader> fDst;
 145
 146     typedef GM INHERITED;
 147 };
 148
 149 //////////////////////////////////////////////////////////////////////////////
 150
 151 static GM* MyFactory(void*) { return new Xfermodes2GM; }
 152 static GMRegistry reg(MyFactory);
 153
 154 }