1
2 /*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8 #include "SampleCode.h"
9 #include "SkView.h"
10 #include "SkCanvas.h"
11 #include "SkCornerPathEffect.h"
12 #include "SkCullPoints.h"
13 #include "SkGradientShader.h"
14 #include "SkPath.h"
15 #include "SkRegion.h"
16 #include "SkShader.h"
17 #include "SkUtils.h"
18 #include "SkRandom.h"
19
addbump(SkPath * path,const SkPoint pts[2],SkScalar bump)20 static void addbump(SkPath* path, const SkPoint pts[2], SkScalar bump) {
21 SkVector tang;
22
23 tang.setLength(pts[1].fX - pts[0].fX, pts[1].fY - pts[0].fY, bump);
24
25 path->lineTo(SkScalarHalf(pts[0].fX + pts[1].fX) - tang.fY,
26 SkScalarHalf(pts[0].fY + pts[1].fY) + tang.fX);
27 path->lineTo(pts[1]);
28 }
29
subdivide(SkPath * path,SkScalar bump)30 static void subdivide(SkPath* path, SkScalar bump) {
31 SkPath::Iter iter(*path, false);
32 SkPoint pts[4];
33 SkPath tmp;
34
35 for (;;)
36 switch (iter.next(pts)) {
37 case SkPath::kMove_Verb:
38 tmp.moveTo(pts[0]);
39 break;
40 case SkPath::kLine_Verb:
41 addbump(&tmp, pts, bump);
42 bump = -bump;
43 break;
44 case SkPath::kDone_Verb:
45 goto FINISH;
46 default:
47 break;
48 }
49
50 FINISH:
51 path->swap(tmp);
52 }
53
getpts(const SkPath & path,int * count)54 static SkIPoint* getpts(const SkPath& path, int* count) {
55 SkPoint pts[4];
56 int n = 1;
57 SkIPoint* array;
58
59 {
60 SkPath::Iter iter(path, false);
61 for (;;)
62 switch (iter.next(pts)) {
63 case SkPath::kLine_Verb:
64 n += 1;
65 break;
66 case SkPath::kDone_Verb:
67 goto FINISHED;
68 default:
69 break;
70 }
71 }
72
73 FINISHED:
74 array = new SkIPoint[n];
75 n = 0;
76
77 {
78 SkPath::Iter iter(path, false);
79 for (;;)
80 switch (iter.next(pts)) {
81 case SkPath::kMove_Verb:
82 array[n++].set(SkScalarRoundToInt(pts[0].fX),
83 SkScalarRoundToInt(pts[0].fY));
84 break;
85 case SkPath::kLine_Verb:
86 array[n++].set(SkScalarRoundToInt(pts[1].fX),
87 SkScalarRoundToInt(pts[1].fY));
88 break;
89 case SkPath::kDone_Verb:
90 goto FINISHED2;
91 default:
92 break;
93 }
94 }
95
96 FINISHED2:
97 *count = n;
98 return array;
99 }
100
nextScalarRange(SkRandom & rand,SkScalar min,SkScalar max)101 static SkScalar nextScalarRange(SkRandom& rand, SkScalar min, SkScalar max) {
102 return min + SkScalarMul(rand.nextUScalar1(), max - min);
103 }
104
105 class CullView : public SampleView {
106 public:
CullView()107 CullView() {
108 fClip.set(0, 0, SkIntToScalar(160), SkIntToScalar(160));
109
110 SkRandom rand;
111
112 for (int i = 0; i < 50; i++) {
113 SkScalar x = nextScalarRange(rand, -fClip.width()*1, fClip.width()*2);
114 SkScalar y = nextScalarRange(rand, -fClip.height()*1, fClip.height()*2);
115 if (i == 0)
116 fPath.moveTo(x, y);
117 else
118 fPath.lineTo(x, y);
119 }
120
121 SkScalar bump = fClip.width()/8;
122 subdivide(&fPath, bump);
123 subdivide(&fPath, bump);
124 subdivide(&fPath, bump);
125 fPoints = getpts(fPath, &fPtCount);
126
127 this->setBGColor(0xFFDDDDDD);
128 }
129
~CullView()130 virtual ~CullView() {
131 delete[] fPoints;
132 }
133
134 protected:
135 // overrides from SkEventSink
onQuery(SkEvent * evt)136 virtual bool onQuery(SkEvent* evt) {
137 if (SampleCode::TitleQ(*evt)) {
138 SampleCode::TitleR(evt, "Culling");
139 return true;
140 }
141 return this->INHERITED::onQuery(evt);
142 }
143
onDrawContent(SkCanvas * canvas)144 virtual void onDrawContent(SkCanvas* canvas) {
145 SkAutoCanvasRestore ar(canvas, true);
146
147 canvas->translate( SkScalarHalf(this->width() - fClip.width()),
148 SkScalarHalf(this->height() - fClip.height()));
149
150 // canvas->scale(SK_Scalar1*3, SK_Scalar1*3, 0, 0);
151
152 SkPaint paint;
153
154 // paint.setAntiAliasOn(true);
155 paint.setStyle(SkPaint::kStroke_Style);
156
157 canvas->drawRect(fClip, paint);
158
159 #if 1
160 paint.setColor(0xFF555555);
161 paint.setStrokeWidth(SkIntToScalar(2));
162 // paint.setPathEffect(new SkCornerPathEffect(SkIntToScalar(30)))->unref();
163 canvas->drawPath(fPath, paint);
164 // paint.setPathEffect(NULL);
165 #endif
166
167 SkPath tmp;
168 SkIRect iclip;
169 fClip.round(&iclip);
170
171 SkCullPointsPath cpp(iclip, &tmp);
172
173 cpp.moveTo(fPoints[0].fX, fPoints[0].fY);
174 for (int i = 0; i < fPtCount; i++)
175 cpp.lineTo(fPoints[i].fX, fPoints[i].fY);
176
177 paint.setColor(SK_ColorRED);
178 paint.setStrokeWidth(SkIntToScalar(3));
179 paint.setStrokeJoin(SkPaint::kRound_Join);
180 canvas->drawPath(tmp, paint);
181
182 this->inval(NULL);
183 }
184
185 private:
186 SkRect fClip;
187 SkIPoint* fPoints;
188 SkPath fPath;
189 int fPtCount;
190
191 typedef SampleView INHERITED;
192 };
193
194 //////////////////////////////////////////////////////////////////////////////
195
MyFactory()196 static SkView* MyFactory() { return new CullView; }
197 static SkViewRegister reg(MyFactory);
198