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