SamplePathEffects.cpp revision 63c684a8a609d39da11b4a656223cebf52ca85dc 
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 "SampleCode.h"
9#include "SkAnimTimer.h"
10#include "SkView.h"
11#include "SkCanvas.h"
12#include "SkGradientShader.h"
13#include "SkPath.h"
14#include "SkRegion.h"
15#include "SkShader.h"
16#include "SkUtils.h"
17#include "Sk1DPathEffect.h"
18#include "SkCornerPathEffect.h"
19#include "SkPathMeasure.h"
20#include "SkRandom.h"
21#include "SkColorPriv.h"
22#include "SkPixelXorXfermode.h"
23
24#define CORNER_RADIUS   12
25
26static const int gXY[] = {
27    4, 0, 0, -4, 8, -4, 12, 0, 8, 4, 0, 4
28};
29
30static SkPathEffect* make_pe(int flags, SkScalar phase) {
31    if (flags == 1)
32        return SkCornerPathEffect::Create(SkIntToScalar(CORNER_RADIUS));
33
34    SkPath  path;
35    path.moveTo(SkIntToScalar(gXY[0]), SkIntToScalar(gXY[1]));
36    for (unsigned i = 2; i < SK_ARRAY_COUNT(gXY); i += 2)
37        path.lineTo(SkIntToScalar(gXY[i]), SkIntToScalar(gXY[i+1]));
38    path.close();
39    path.offset(SkIntToScalar(-6), 0);
40
41    SkPathEffect* outer = SkPath1DPathEffect::Create(path, 12, phase,
42                                                     SkPath1DPathEffect::kRotate_Style);
43
44    if (flags == 2)
45        return outer;
46
47    SkPathEffect* inner = SkCornerPathEffect::Create(SkIntToScalar(CORNER_RADIUS));
48
49    SkPathEffect* pe = SkComposePathEffect::Create(outer, inner);
50    outer->unref();
51    inner->unref();
52    return pe;
53}
54
55static SkPathEffect* make_warp_pe(SkScalar phase) {
56    SkPath  path;
57    path.moveTo(SkIntToScalar(gXY[0]), SkIntToScalar(gXY[1]));
58    for (unsigned i = 2; i < SK_ARRAY_COUNT(gXY); i += 2)
59        path.lineTo(SkIntToScalar(gXY[i]), SkIntToScalar(gXY[i+1]));
60    path.close();
61    path.offset(SkIntToScalar(-6), 0);
62
63    SkPathEffect* outer = SkPath1DPathEffect::Create(
64        path, 12, phase, SkPath1DPathEffect::kMorph_Style);
65    SkPathEffect* inner = SkCornerPathEffect::Create(SkIntToScalar(CORNER_RADIUS));
66
67    SkPathEffect* pe = SkComposePathEffect::Create(outer, inner);
68    outer->unref();
69    inner->unref();
70    return pe;
71}
72
73///////////////////////////////////////////////////////////
74
75#include "SkColorFilter.h"
76#include "SkLayerRasterizer.h"
77
78class TestRastBuilder : public SkLayerRasterizer::Builder {
79public:
80    TestRastBuilder() {
81        SkPaint paint;
82        paint.setAntiAlias(true);
83
84        paint.setAlpha(0x66);
85        this->addLayer(paint, SkIntToScalar(4), SkIntToScalar(4));
86
87        paint.setAlpha(0xFF);
88        this->addLayer(paint);
89    }
90};
91
92class PathEffectView : public SampleView {
93    SkPath  fPath;
94    SkPoint fClickPt;
95    SkScalar fPhase;
96
97public:
98    PathEffectView() : fPhase(0) {
99        }
100
101protected:
102    void onOnceBeforeDraw() SK_OVERRIDE {
103        SkRandom    rand;
104        int         steps = 20;
105        SkScalar    dist = SkIntToScalar(400);
106        SkScalar    x = SkIntToScalar(20);
107        SkScalar    y = SkIntToScalar(50);
108
109        fPath.moveTo(x, y);
110        for (int i = 0; i < steps; i++) {
111            x += dist/steps;
112            SkScalar tmpY = y + SkIntToScalar(rand.nextS() % 25);
113            if (i == steps/2) {
114                fPath.moveTo(x, tmpY);
115            } else {
116                fPath.lineTo(x, tmpY);
117            }
118        }
119
120        {
121            SkRect  oval;
122            oval.set(SkIntToScalar(20), SkIntToScalar(30),
123                     SkIntToScalar(100), SkIntToScalar(60));
124            oval.offset(x, 0);
125            fPath.addRoundRect(oval, SkIntToScalar(8), SkIntToScalar(8));
126        }
127
128        fClickPt.set(SkIntToScalar(200), SkIntToScalar(200));
129
130        this->setBGColor(0xFFDDDDDD);
131    }
132
133    bool onQuery(SkEvent* evt) SK_OVERRIDE {
134        if (SampleCode::TitleQ(*evt)) {
135            SampleCode::TitleR(evt, "PathEffects");
136            return true;
137        }
138        return this->INHERITED::onQuery(evt);
139    }
140
141    void onDrawContent(SkCanvas* canvas) SK_OVERRIDE {
142        SkPaint paint;
143
144        canvas->translate(0, 50);
145
146        paint.setColor(SK_ColorBLUE);
147        paint.setPathEffect(make_pe(2, fPhase))->unref();
148        canvas->drawPath(fPath, paint);
149
150        canvas->translate(0, 50);
151
152        paint.setARGB(0xFF, 0, 0xBB, 0);
153        paint.setPathEffect(make_pe(3, fPhase))->unref();
154        canvas->drawPath(fPath, paint);
155
156        canvas->translate(0, 50);
157
158        paint.setARGB(0xFF, 0, 0, 0);
159        paint.setPathEffect(make_warp_pe(fPhase))->unref();
160        TestRastBuilder testRastBuilder;
161        paint.setRasterizer(testRastBuilder.detachRasterizer())->unref();
162        canvas->drawPath(fPath, paint);
163    }
164
165    bool onAnimate(const SkAnimTimer& timer) SK_OVERRIDE {
166        fPhase = timer.scaled(40);
167        return true;
168    }
169
170private:
171    typedef SampleView INHERITED;
172};
173
174//////////////////////////////////////////////////////////////////////////////
175
176static SkView* MyFactory() { return new PathEffectView; }
177static SkViewRegister reg(MyFactory);
178