xref: /aosp_15_r20/external/skia/gm/clip_sierpinski_region.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2019 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/gm.h"
9 
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkPaint.h"
12 #include "include/core/SkRegion.h"
13 
14 static constexpr int kSize = 3*3*3*3*3;
15 static constexpr int kTrans = 10;
16 
17 DEF_SIMPLE_GM(clip_sierpinski_region, canvas, 2*kTrans + kSize, 2*kTrans + kSize) {
18     SkRegion region;
19     static constexpr int kSteps = 4;
20     int n = 1;
21     SkScalar s = kSize/3.f;
22     for (int i = 0; i < kSteps; ++i, n*=3, s/=3.f) {
23         for (int x = 0; x < n; ++x) {
24             for (int y = 0; y < n; ++y) {
25                 region.op(SkIRect::MakeXYWH((3*x + 1)*s, (3*y + 1)*s, s, s), SkRegion::kUnion_Op);
26             }
27         }
28     }
29     // Test that a save layer with an offset works as expected.
30     region.translate(kTrans, kTrans);
31     canvas->saveLayer(SkRect::MakeXYWH(kTrans, kTrans, 1000, 1000), nullptr);
32     // Make sure the clip call ignores the CTM.
33     canvas->rotate(25.f, 50.f, 50.f);
34     canvas->clipRegion(region);
35     SkPaint red;
36     red.setColor(SK_ColorRED);
37     canvas->drawPaint(red);
38     canvas->restore();
39 }
40