1 /*
2  * Copyright 2011 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 "Sample.h"
9 #include "SkAnimTimer.h"
10 #include "SkCanvas.h"
11 #include "SkGradientShader.h"
12 #include "SkPath.h"
13 #include "SkRegion.h"
14 #include "SkShader.h"
15 #include "SkUTF.h"
16 #include "Sk1DPathEffect.h"
17 #include "SkCornerPathEffect.h"
18 #include "SkPathMeasure.h"
19 #include "SkRandom.h"
20 #include "SkColorPriv.h"
21 
22 #define CORNER_RADIUS   12
23 
24 static const int gXY[] = {
25     4, 0, 0, -4, 8, -4, 12, 0, 8, 4, 0, 4
26 };
27 
make_pe(int flags,SkScalar phase)28 static sk_sp<SkPathEffect> make_pe(int flags, SkScalar phase) {
29     if (flags == 1) {
30         return SkCornerPathEffect::Make(SkIntToScalar(CORNER_RADIUS));
31     }
32 
33     SkPath  path;
34     path.moveTo(SkIntToScalar(gXY[0]), SkIntToScalar(gXY[1]));
35     for (unsigned i = 2; i < SK_ARRAY_COUNT(gXY); i += 2)
36         path.lineTo(SkIntToScalar(gXY[i]), SkIntToScalar(gXY[i+1]));
37     path.close();
38     path.offset(SkIntToScalar(-6), 0);
39 
40     auto outer = SkPath1DPathEffect::Make(path, 12, phase, SkPath1DPathEffect::kRotate_Style);
41 
42     if (flags == 2)
43         return outer;
44 
45     auto inner = SkCornerPathEffect::Make(SkIntToScalar(CORNER_RADIUS));
46 
47     return SkPathEffect::MakeCompose(outer, inner);
48 }
49 
make_warp_pe(SkScalar phase)50 static sk_sp<SkPathEffect> make_warp_pe(SkScalar phase) {
51     SkPath  path;
52     path.moveTo(SkIntToScalar(gXY[0]), SkIntToScalar(gXY[1]));
53     for (unsigned i = 2; i < SK_ARRAY_COUNT(gXY); i += 2) {
54         path.lineTo(SkIntToScalar(gXY[i]), SkIntToScalar(gXY[i+1]));
55     }
56     path.close();
57     path.offset(SkIntToScalar(-6), 0);
58 
59     auto outer = SkPath1DPathEffect::Make(
60         path, 12, phase, SkPath1DPathEffect::kMorph_Style);
61     auto inner = SkCornerPathEffect::Make(SkIntToScalar(CORNER_RADIUS));
62 
63     return SkPathEffect::MakeCompose(outer, inner);
64 }
65 
66 ///////////////////////////////////////////////////////////
67 
68 #include "SkColorFilter.h"
69 
70 class PathEffectView : public Sample {
71     SkPath  fPath;
72     SkPoint fClickPt;
73     SkScalar fPhase;
74 
75 public:
PathEffectView()76     PathEffectView() : fPhase(0) {
77         }
78 
79 protected:
onOnceBeforeDraw()80     void onOnceBeforeDraw() override {
81         SkRandom    rand;
82         int         steps = 20;
83         SkScalar    dist = SkIntToScalar(400);
84         SkScalar    x = SkIntToScalar(20);
85         SkScalar    y = SkIntToScalar(50);
86 
87         fPath.moveTo(x, y);
88         for (int i = 0; i < steps; i++) {
89             x += dist/steps;
90             SkScalar tmpY = y + SkIntToScalar(rand.nextS() % 25);
91             if (i == steps/2) {
92                 fPath.moveTo(x, tmpY);
93             } else {
94                 fPath.lineTo(x, tmpY);
95             }
96         }
97 
98         {
99             SkRect  oval;
100             oval.set(SkIntToScalar(20), SkIntToScalar(30),
101                      SkIntToScalar(100), SkIntToScalar(60));
102             oval.offset(x, 0);
103             fPath.addRoundRect(oval, SkIntToScalar(8), SkIntToScalar(8));
104         }
105 
106         fClickPt.set(SkIntToScalar(200), SkIntToScalar(200));
107 
108         this->setBGColor(0xFFDDDDDD);
109     }
110 
onQuery(Sample::Event * evt)111     bool onQuery(Sample::Event* evt) override {
112         if (Sample::TitleQ(*evt)) {
113             Sample::TitleR(evt, "PathEffects");
114             return true;
115         }
116         return this->INHERITED::onQuery(evt);
117     }
118 
onDrawContent(SkCanvas * canvas)119     void onDrawContent(SkCanvas* canvas) override {
120         SkPaint paint;
121 
122         canvas->translate(0, 50);
123 
124         paint.setColor(SK_ColorBLUE);
125         paint.setPathEffect(make_pe(2, fPhase));
126         canvas->drawPath(fPath, paint);
127 
128         canvas->translate(0, 50);
129 
130         paint.setARGB(0xFF, 0, 0xBB, 0);
131         paint.setPathEffect(make_pe(3, fPhase));
132         canvas->drawPath(fPath, paint);
133 
134         canvas->translate(0, 50);
135 
136         paint.setARGB(0xFF, 0, 0, 0);
137         paint.setPathEffect(make_warp_pe(fPhase));
138         canvas->drawPath(fPath, paint);
139     }
140 
onAnimate(const SkAnimTimer & timer)141     bool onAnimate(const SkAnimTimer& timer) override {
142         fPhase = timer.scaled(40);
143         return true;
144     }
145 
146 private:
147     typedef Sample INHERITED;
148 };
149 
150 //////////////////////////////////////////////////////////////////////////////
151 
152 DEF_SAMPLE( return new PathEffectView(); )
153