xref: /aosp_15_r20/external/skia/gm/arcofzorro.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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/gm.h"
9 #include "include/core/SkCanvas.h"
10 #include "include/core/SkColor.h"
11 #include "include/core/SkPaint.h"
12 #include "include/core/SkRect.h"
13 #include "include/core/SkScalar.h"
14 #include "include/core/SkSize.h"
15 #include "include/core/SkString.h"
16 #include "src/base/SkRandom.h"
17 
18 namespace skiagm {
19 
20 // This GM draws a lot of arcs in a 'Z' shape. It particularly exercises
21 // the 'drawArc' code near a singularly of its processing (i.e., near the
22 // edge of one of its underlying quads).
23 class ArcOfZorroGM : public GM {
24 public:
ArcOfZorroGM()25     ArcOfZorroGM() {
26         this->setBGColor(0xFFCCCCCC);
27     }
28 
29 protected:
getName() const30     SkString getName() const override { return SkString("arcofzorro"); }
31 
getISize()32     SkISize getISize() override { return SkISize::Make(1000, 1000); }
33 
onDraw(SkCanvas * canvas)34     void onDraw(SkCanvas* canvas) override {
35         SkRandom rand;
36 
37         SkRect rect = SkRect::MakeXYWH(10, 10, 200, 200);
38 
39         SkPaint p;
40 
41         p.setStyle(SkPaint::kStroke_Style);
42         p.setStrokeWidth(35);
43         int xOffset = 0, yOffset = 0;
44         int direction = 0;
45 
46         for (float arc = 134.0f; arc < 136.0f; arc += 0.01f) {
47             SkColor color = rand.nextU();
48             color |= 0xff000000;
49             p.setColor(color);
50 
51             canvas->save();
52             canvas->translate(SkIntToScalar(xOffset), SkIntToScalar(yOffset));
53             canvas->drawArc(rect, 0, arc, false, p);
54             canvas->restore();
55 
56             switch (direction) {
57             case 0:
58                 xOffset += 10;
59                 if (xOffset >= 700) {
60                     direction = 1;
61                 }
62                 break;
63             case 1:
64                 xOffset -= 10;
65                 yOffset += 10;
66                 if (xOffset < 50) {
67                     direction = 2;
68                 }
69                 break;
70             case 2:
71                 xOffset += 10;
72                 break;
73             }
74         }
75 
76     }
77 
78 private:
79     using INHERITED = GM;
80 };
81 
82 //////////////////////////////////////////////////////////////////////////////
83 
84 DEF_GM(return new ArcOfZorroGM;)
85 }  // namespace skiagm
86