gm/clipdrawdraw.cpp

   1 /*
   2  * Copyright 2014 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 "sk_tool_utils.h"
  10 #include "SkRegion.h"
  11
  12 // This GM exercises the use case found in crbug.com/423834.
  13 // The following pattern:
  14 //    save();
  15 //    clipRect(rect, noAA);
  16 //    drawRect(bigRect, noAA);
  17 //    restore();
  18 //
  19 //    drawRect(rect, noAA);
  20 // can leave 1 pixel wide remnants of the first rect.
  21 static void Draw(SkCanvas* canvas, const SkRect& rect) {
  22         SkPaint p;
  23         p.setAntiAlias(false);
  24
  25         const SkRect bigRect = SkRect::MakeWH(600, 600);
  26
  27         canvas->save();
  28             // draw a black rect through the clip
  29             canvas->save();
  30                 canvas->clipRect(rect);
  31                 canvas->drawRect(bigRect, p);
  32             canvas->restore();
  33
  34             // now draw the white rect on top
  35             p.setColor(SK_ColorWHITE);
  36             canvas->drawRect(rect, p);
  37         canvas->restore();
  38 }
  39
  40 DEF_SIMPLE_GM_BG(clipdrawdraw, canvas, 512, 512,
  41                  sk_tool_utils::color_to_565(0xFFCCCCCC)) {
  42         // Vertical remnant
  43         const SkRect rect1 = SkRect::MakeLTRB(136.5f, 137.5f, 338.5f, 293.5f);
  44
  45         // Horizontal remnant
  46         // 179.488 rounds the right way (i.e., 179), 179.499 rounds the wrong way (i.e., 180)
  47         const SkRect rect2 = SkRect::MakeLTRB(207.5f, 179.499f, 530.5f, 429.5f);
  48
  49         Draw(canvas, rect1);
  50         Draw(canvas, rect2);
  51 }
  52
  53 ///////////////////////////////////////////////////////////////////////////////////////////////////
  54
  55 DEF_SIMPLE_GM(clip_region, canvas, 256, 256) {
  56     SkRegion rgn({ 10, 10, 100, 100 });
  57
  58     canvas->save();
  59     canvas->clipRegion(rgn);
  60     canvas->drawColor(SK_ColorRED);
  61     canvas->restore();
  62
  63     SkRect bounds = { 30, 30, 80, 80 };
  64     canvas->saveLayer(&bounds, nullptr);
  65     canvas->clipRegion(rgn);
  66     canvas->drawColor(SK_ColorBLUE);
  67     canvas->restore();
  68 }