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 "SampleCode.h"
9 #include "SkCanvas.h"
10 #include "SkPath.h"
11
12 // Reproduces https://code.google.com/p/chromium/issues/detail?id=279014
13
14 // Renders a string art shape.
15 // The particular shape rendered can be controlled by clicking horizontally, thereby
16 // generating an angle from 0 to 1.
17
18 class StringArtView : public SampleView {
19 public:
StringArtView()20 StringArtView() : fAngle(0.305f) {}
21
22 protected:
23 // overrides from SkEventSink
onQuery(SkEvent * evt)24 bool onQuery(SkEvent* evt) override {
25 if (SampleCode::TitleQ(*evt)) {
26 SampleCode::TitleR(evt, "StringArt");
27 return true;
28 }
29 return this->INHERITED::onQuery(evt);
30 }
31
onDrawContent(SkCanvas * canvas)32 void onDrawContent(SkCanvas* canvas) override {
33 SkScalar angle = fAngle*SK_ScalarPI + SkScalarHalf(SK_ScalarPI);
34
35 SkPoint center = SkPoint::Make(SkScalarHalf(this->width()), SkScalarHalf(this->height()));
36 SkScalar length = 5;
37 SkScalar step = angle;
38
39 SkPath path;
40 path.moveTo(center);
41
42 while (length < (SkScalarHalf(SkMinScalar(this->width(), this->height())) - 10.f))
43 {
44 SkPoint rp = SkPoint::Make(length*SkScalarCos(step) + center.fX,
45 length*SkScalarSin(step) + center.fY);
46 path.lineTo(rp);
47 length += angle / SkScalarHalf(SK_ScalarPI);
48 step += angle;
49 }
50 path.close();
51
52 SkPaint paint;
53 paint.setAntiAlias(true);
54 paint.setStyle(SkPaint::kStroke_Style);
55 paint.setColor(0xFF007700);
56
57 canvas->drawPath(path, paint);
58 }
59
onFindClickHandler(SkScalar x,SkScalar y,unsigned)60 SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned) override {
61 fAngle = x/width();
62 this->inval(nullptr);
63 return nullptr;
64 }
65 private:
66
67 SkScalar fAngle;
68 typedef SampleView INHERITED;
69 };
70
71 //////////////////////////////////////////////////////////////////////////////
72
MyFactory()73 static SkView* MyFactory() { return new StringArtView; }
74 static SkViewRegister reg(MyFactory);
75