gm/imagealphathreshold.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
   8 #include "gm.h"
   9 #include "SkAlphaThresholdFilter.h"
  10 #include "SkRandom.h"
  11
  12 #define WIDTH 500
  13 #define HEIGHT 500
  14
  15 namespace skiagm {
  16
  17 class ImageAlphaThresholdGM : public GM {
  18 public:
  19     ImageAlphaThresholdGM() {
  20         this->setBGColor(0xFFFFFFFF);
  21     }
  22
  23 protected:
  24
  25     SkString onShortName() SK_OVERRIDE {
  26         return SkString("imagealphathreshold");
  27     }
  28
  29     SkISize onISize() SK_OVERRIDE {
  30         return SkISize::Make(WIDTH, HEIGHT);
  31     }
  32
  33     void onDraw(SkCanvas* canvas) SK_OVERRIDE {
  34         SkIRect rects[2];
  35         rects[0] = SkIRect::MakeXYWH(0, 150, WIDTH, HEIGHT - 300);
  36         rects[1] = SkIRect::MakeXYWH(150, 0, WIDTH - 300, HEIGHT);
  37         SkRegion region;
  38         region.setRects(rects, 2);
  39
  40         SkMatrix matrix;
  41         matrix.reset();
  42         matrix.setTranslate(WIDTH * .1f, HEIGHT * .1f);
  43         matrix.postScale(.8f, .8f);
  44
  45         canvas->concat(matrix);
  46
  47         SkPaint paint;
  48         paint.setImageFilter(
  49             SkAlphaThresholdFilter::Create(region, 0.2f, 0.7f))->unref();
  50         canvas->saveLayer(NULL, &paint);
  51         paint.setAntiAlias(true);
  52
  53         SkPaint rect_paint;
  54         rect_paint.setColor(0xFF0000FF);
  55         canvas->drawRect(SkRect::MakeXYWH(0, 0, WIDTH / 2, HEIGHT / 2),
  56                          rect_paint);
  57         rect_paint.setColor(0xBFFF0000);
  58         canvas->drawRect(SkRect::MakeXYWH(WIDTH / 2, 0, WIDTH / 2, HEIGHT / 2),
  59                          rect_paint);
  60         rect_paint.setColor(0x3F00FF00);
  61         canvas->drawRect(SkRect::MakeXYWH(0, HEIGHT / 2, WIDTH / 2, HEIGHT / 2),
  62                          rect_paint);
  63         rect_paint.setColor(0x00000000);
  64         canvas->drawRect(SkRect::MakeXYWH(WIDTH / 2, HEIGHT / 2, WIDTH / 2, HEIGHT / 2),
  65                          rect_paint);
  66
  67         canvas->restore();
  68     }
  69
  70 private:
  71     typedef GM INHERITED;
  72 };
  73
  74 //////////////////////////////////////////////////////////////////////////////
  75
  76 static GM* MyFactory(void*) { return new ImageAlphaThresholdGM; }
  77 static GMRegistry reg(MyFactory);
  78
  79 }