src/third_party/skia/gm/bitmapshader.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
  10 #include "SkBitmap.h"
  11 #include "SkPaint.h"
  12 #include "SkShader.h"
  13
  14 namespace skiagm {
  15
  16 static void draw_bm(SkBitmap* bm) {
  17     SkPaint bluePaint;
  18     bluePaint.setColor(SK_ColorBLUE);
  19
  20     bm->allocN32Pixels(20, 20);
  21     bm->eraseColor(SK_ColorRED);
  22
  23     SkCanvas canvas(*bm);
  24     canvas.drawCircle(10, 10, 5, bluePaint);
  25 }
  26
  27 static void draw_mask(SkBitmap* bm) {
  28     SkPaint circlePaint;
  29     circlePaint.setColor(SK_ColorBLACK);
  30
  31     bm->allocPixels(SkImageInfo::MakeA8(20, 20));
  32     bm->eraseColor(SK_ColorTRANSPARENT);
  33
  34     SkCanvas canvas(*bm);
  35     canvas.drawCircle(10, 10, 10, circlePaint);
  36 }
  37
  38 static void adopt_shader(SkPaint* paint, SkShader* shader) {
  39     paint->setShader(shader);
  40     SkSafeUnref(shader);
  41 }
  42
  43 class BitmapShaderGM : public GM {
  44 public:
  45
  46     BitmapShaderGM() {
  47         this->setBGColor(SK_ColorGRAY);
  48         draw_bm(&fBitmap);
  49         draw_mask(&fMask);
  50     }
  51
  52 protected:
  53     virtual SkString onShortName() {
  54         return SkString("bitmapshaders");
  55     }
  56
  57     virtual SkISize onISize() {
  58         return SkISize::Make(150, 100);
  59     }
  60
  61     virtual void onDraw(SkCanvas* canvas) {
  62         SkPaint paint;
  63
  64         for (int i = 0; i < 2; i++) {
  65             SkMatrix s;
  66             s.reset();
  67             if (1 == i) {
  68                 s.setScale(1.5f, 1.5f);
  69                 s.postTranslate(2, 2);
  70             }
  71
  72             canvas->save();
  73             adopt_shader(&paint, SkShader::CreateBitmapShader(fBitmap, SkShader::kClamp_TileMode,
  74                                                               SkShader::kClamp_TileMode, &s));
  75
  76             // draw the shader with a bitmap mask
  77             canvas->drawBitmap(fMask, 0, 0, &paint);
  78             canvas->drawBitmap(fMask, 30, 0, &paint);
  79
  80             canvas->translate(0, 25);
  81
  82             canvas->drawCircle(10, 10, 10, paint);
  83             canvas->drawCircle(40, 10, 10, paint); // no blue circle expected
  84
  85             canvas->translate(0, 25);
  86
  87             // clear the shader, colorized by a solid color with a bitmap mask
  88             paint.setShader(NULL);
  89             paint.setColor(SK_ColorGREEN);
  90             canvas->drawBitmap(fMask, 0, 0, &paint);
  91             canvas->drawBitmap(fMask, 30, 0, &paint);
  92
  93             canvas->translate(0, 25);
  94
  95             adopt_shader(&paint, SkShader::CreateBitmapShader(fMask, SkShader::kRepeat_TileMode,
  96                                                               SkShader::kRepeat_TileMode, &s));
  97             paint.setColor(SK_ColorRED);
  98
  99             // draw the mask using the shader and a color
 100             canvas->drawRect(SkRect::MakeXYWH(0, 0, 20, 20), paint);
 101             canvas->drawRect(SkRect::MakeXYWH(30, 0, 20, 20), paint);
 102             canvas->restore();
 103             canvas->translate(60, 0);
 104         }
 105     }
 106
 107 private:
 108     SkBitmap fBitmap;
 109     SkBitmap fMask;
 110
 111     typedef GM INHERITED;
 112 };
 113
 114 //////////////////////////////////////////////////////////////////////////////
 115
 116 static GM* MyFactory(void*) { return new BitmapShaderGM; }
 117 static GMRegistry reg(MyFactory);
 118
 119 }