1/*
2 * Copyright 2012 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 "gm.h"
8#include "SkCanvas.h"
9#include "SkPaint.h"
10#include "Sk1DPathEffect.h"
11#include "Sk2DPathEffect.h"
12#include "SkCornerPathEffect.h"
13#include "SkDashPathEffect.h"
14#include "SkDiscretePathEffect.h"
15
16namespace skiagm {
17
18static void compose_pe(SkPaint* paint) {
19    SkPathEffect* pe = paint->getPathEffect();
20    SkPathEffect* corner = SkCornerPathEffect::Create(25);
21    SkPathEffect* compose;
22    if (pe) {
23        compose = SkComposePathEffect::Create(pe, corner);
24        corner->unref();
25    } else {
26        compose = corner;
27    }
28    paint->setPathEffect(compose)->unref();
29}
30
31static void hair_pe(SkPaint* paint) {
32    paint->setStrokeWidth(0);
33}
34
35static void hair2_pe(SkPaint* paint) {
36    paint->setStrokeWidth(0);
37    compose_pe(paint);
38}
39
40static void stroke_pe(SkPaint* paint) {
41    paint->setStrokeWidth(12);
42    compose_pe(paint);
43}
44
45static void dash_pe(SkPaint* paint) {
46    SkScalar inter[] = { 20, 10, 10, 10 };
47    paint->setStrokeWidth(12);
48    paint->setPathEffect(SkDashPathEffect::Create(inter, SK_ARRAY_COUNT(inter),
49                                                  0))->unref();
50    compose_pe(paint);
51}
52
53static const int gXY[] = {
544, 0, 0, -4, 8, -4, 12, 0, 8, 4, 0, 4
55};
56
57static void scale(SkPath* path, SkScalar scale) {
58    SkMatrix m;
59    m.setScale(scale, scale);
60    path->transform(m);
61}
62
63static void one_d_pe(SkPaint* paint) {
64    SkPath  path;
65    path.moveTo(SkIntToScalar(gXY[0]), SkIntToScalar(gXY[1]));
66    for (unsigned i = 2; i < SK_ARRAY_COUNT(gXY); i += 2)
67        path.lineTo(SkIntToScalar(gXY[i]), SkIntToScalar(gXY[i+1]));
68    path.close();
69    path.offset(SkIntToScalar(-6), 0);
70    scale(&path, 1.5f);
71
72    paint->setPathEffect(SkPath1DPathEffect::Create(path, SkIntToScalar(21), 0,
73                                SkPath1DPathEffect::kRotate_Style))->unref();
74    compose_pe(paint);
75}
76
77typedef void (*PE_Proc)(SkPaint*);
78static const PE_Proc gPE[] = { hair_pe, hair2_pe, stroke_pe, dash_pe, one_d_pe };
79
80static void fill_pe(SkPaint* paint) {
81    paint->setStyle(SkPaint::kFill_Style);
82    paint->setPathEffect(NULL);
83}
84
85static void discrete_pe(SkPaint* paint) {
86    paint->setPathEffect(SkDiscretePathEffect::Create(10, 4))->unref();
87}
88
89static SkPathEffect* MakeTileEffect() {
90    SkMatrix m;
91    m.setScale(SkIntToScalar(12), SkIntToScalar(12));
92
93    SkPath path;
94    path.addCircle(0, 0, SkIntToScalar(5));
95
96    return SkPath2DPathEffect::Create(m, path);
97}
98
99static void tile_pe(SkPaint* paint) {
100    paint->setPathEffect(MakeTileEffect())->unref();
101}
102
103static const PE_Proc gPE2[] = { fill_pe, discrete_pe, tile_pe };
104
105class PathEffectGM : public GM {
106public:
107    PathEffectGM() {}
108
109protected:
110    virtual uint32_t onGetFlags() const SK_OVERRIDE {
111        return kSkipTiled_Flag;
112    }
113
114    SkString onShortName() {
115        return SkString("patheffect");
116    }
117
118    SkISize onISize() { return SkISize::Make(800, 600); }
119
120    virtual void onDraw(SkCanvas* canvas) {
121        SkPaint paint;
122        paint.setAntiAlias(true);
123        paint.setStyle(SkPaint::kStroke_Style);
124
125        SkPath path;
126        path.moveTo(20, 20);
127        path.lineTo(70, 120);
128        path.lineTo(120, 30);
129        path.lineTo(170, 80);
130        path.lineTo(240, 50);
131
132        size_t i;
133        canvas->save();
134        for (i = 0; i < SK_ARRAY_COUNT(gPE); i++) {
135            gPE[i](&paint);
136            canvas->drawPath(path, paint);
137            canvas->translate(0, 75);
138        }
139        canvas->restore();
140
141        path.reset();
142        SkRect r = { 0, 0, 250, 120 };
143        path.addOval(r, SkPath::kCW_Direction);
144        r.inset(50, 50);
145        path.addRect(r, SkPath::kCCW_Direction);
146
147        canvas->translate(320, 20);
148        for (i = 0; i < SK_ARRAY_COUNT(gPE2); i++) {
149            gPE2[i](&paint);
150            canvas->drawPath(path, paint);
151            canvas->translate(0, 160);
152        }
153
154        SkIRect rect = SkIRect::MakeXYWH(20, 20, 60, 60);
155        for (i = 0; i < SK_ARRAY_COUNT(gPE); i++) {
156            SkPaint p;
157            p.setAntiAlias(true);
158            p.setStyle(SkPaint::kFill_Style);
159            gPE[i](&p);
160            canvas->drawIRect(rect, p);
161            canvas->translate(75, 0);
162        }
163    }
164
165private:
166    typedef GM INHERITED;
167};
168
169//////////////////////////////////////////////////////////////////////////////
170
171static GM* PathEffectFactory(void*) { return new PathEffectGM; }
172static GMRegistry regPathEffect(PathEffectFactory);
173
174}
175