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 "SkGradientShader.h"
12 #include "SkGraphics.h"
13 #include "SkImageDecoder.h"
14 #include "SkPath.h"
15 #include "SkRegion.h"
16 #include "SkShader.h"
17 #include "SkUtils.h"
18 #include "SkXfermode.h"
19 #include "SkColorPriv.h"
20 #include "SkColorFilter.h"
21 #include "SkTime.h"
22 #include "SkRandom.h"
23
24 #include "SkLineClipper.h"
25 #include "SkEdgeClipper.h"
26
27 #define AUTO_ANIMATE true
28
test0(SkPoint pts[],SkRect * clip)29 static int test0(SkPoint pts[], SkRect* clip) {
30 pts[0].set(200000, 140);
31 pts[1].set(-740000, 483);
32 pts[2].set(1.00000102e-06f, 9.10000017e-05f);
33 clip->set(0, 0, 640, 480);
34 return 2;
35 }
36
37 ///////////////////////////////////////////////////////////////////////////////
38
drawQuad(SkCanvas * canvas,const SkPoint pts[3],const SkPaint & p)39 static void drawQuad(SkCanvas* canvas, const SkPoint pts[3], const SkPaint& p) {
40 SkPath path;
41 path.moveTo(pts[0]);
42 path.quadTo(pts[1], pts[2]);
43 canvas->drawPath(path, p);
44 }
45
drawCubic(SkCanvas * canvas,const SkPoint pts[4],const SkPaint & p)46 static void drawCubic(SkCanvas* canvas, const SkPoint pts[4], const SkPaint& p) {
47 SkPath path;
48 path.moveTo(pts[0]);
49 path.cubicTo(pts[1], pts[2], pts[3]);
50 canvas->drawPath(path, p);
51 }
52
53 typedef void (*clipper_proc)(const SkPoint src[], const SkRect& clip,
54 SkCanvas*, const SkPaint&, const SkPaint&);
55
check_clipper(int count,const SkPoint pts[],const SkRect & clip)56 static void check_clipper(int count, const SkPoint pts[], const SkRect& clip) {
57 for (int i = 0; i < count; i++) {
58 SkASSERT(pts[i].fX >= clip.fLeft);
59 SkASSERT(pts[i].fX <= clip.fRight);
60 SkASSERT(pts[i].fY >= clip.fTop);
61 SkASSERT(pts[i].fY <= clip.fBottom);
62 }
63
64 if (count > 1) {
65 sk_assert_monotonic_y(pts, count);
66 }
67 }
68
line_intersector(const SkPoint src[],const SkRect & clip,SkCanvas * canvas,const SkPaint & p0,const SkPaint & p1)69 static void line_intersector(const SkPoint src[], const SkRect& clip,
70 SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
71 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, src, p1);
72
73 SkPoint dst[2];
74 if (SkLineClipper::IntersectLine(src, clip, dst)) {
75 check_clipper(2, dst, clip);
76 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, dst, p0);
77 }
78 }
79
line_clipper(const SkPoint src[],const SkRect & clip,SkCanvas * canvas,const SkPaint & p0,const SkPaint & p1)80 static void line_clipper(const SkPoint src[], const SkRect& clip,
81 SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
82 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, src, p1);
83
84 SkPoint dst[SkLineClipper::kMaxPoints];
85 int count = SkLineClipper::ClipLine(src, clip, dst);
86 for (int i = 0; i < count; i++) {
87 check_clipper(2, &dst[i], clip);
88 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, &dst[i], p0);
89 }
90 }
91
quad_clipper(const SkPoint src[],const SkRect & clip,SkCanvas * canvas,const SkPaint & p0,const SkPaint & p1)92 static void quad_clipper(const SkPoint src[], const SkRect& clip,
93 SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
94 drawQuad(canvas, src, p1);
95
96 SkEdgeClipper clipper;
97 if (clipper.clipQuad(src, clip)) {
98 SkPoint pts[4];
99 SkPath::Verb verb;
100 while ((verb = clipper.next(pts)) != SkPath::kDone_Verb) {
101 switch (verb) {
102 case SkPath::kLine_Verb:
103 check_clipper(2, pts, clip);
104 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, pts, p0);
105 break;
106 case SkPath::kQuad_Verb:
107 check_clipper(3, pts, clip);
108 drawQuad(canvas, pts, p0);
109 break;
110 default:
111 SkASSERT(!"unexpected verb");
112 }
113 }
114 }
115 }
116
cubic_clipper(const SkPoint src[],const SkRect & clip,SkCanvas * canvas,const SkPaint & p0,const SkPaint & p1)117 static void cubic_clipper(const SkPoint src[], const SkRect& clip,
118 SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
119 drawCubic(canvas, src, p1);
120
121 SkEdgeClipper clipper;
122 if (clipper.clipCubic(src, clip)) {
123 SkPoint pts[4];
124 SkPath::Verb verb;
125 while ((verb = clipper.next(pts)) != SkPath::kDone_Verb) {
126 switch (verb) {
127 case SkPath::kLine_Verb:
128 check_clipper(2, pts, clip);
129 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, pts, p0);
130 break;
131 case SkPath::kCubic_Verb:
132 // check_clipper(4, pts, clip);
133 drawCubic(canvas, pts, p0);
134 break;
135 default:
136 SkASSERT(!"unexpected verb");
137 }
138 }
139 }
140 }
141
142 static const clipper_proc gProcs[] = {
143 line_intersector,
144 line_clipper,
145 quad_clipper,
146 cubic_clipper
147 };
148
149 ///////////////////////////////////////////////////////////////////////////////
150
151 enum {
152 W = 640/3,
153 H = 480/3
154 };
155
156 class LineClipperView : public SampleView {
157 SkMSec fNow;
158 int fCounter;
159 int fProcIndex;
160 SkRect fClip;
161 SkRandom fRand;
162 SkPoint fPts[4];
163
randPts()164 void randPts() {
165 for (size_t i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
166 fPts[i].set(fRand.nextUScalar1() * 640,
167 fRand.nextUScalar1() * 480);
168 }
169 fCounter += 1;
170 }
171
172 public:
LineClipperView()173 LineClipperView() {
174 fProcIndex = 0;
175 fCounter = 0;
176 fNow = 0;
177
178 int x = (640 - W)/2;
179 int y = (480 - H)/2;
180 fClip.set(SkIntToScalar(x), SkIntToScalar(y),
181 SkIntToScalar(x + W), SkIntToScalar(y + H));
182 this->randPts();
183 }
184
185 protected:
186 // overrides from SkEventSink
onQuery(SkEvent * evt)187 virtual bool onQuery(SkEvent* evt) {
188 if (SampleCode::TitleQ(*evt)) {
189 SampleCode::TitleR(evt, "LineClipper");
190 return true;
191 }
192 return this->INHERITED::onQuery(evt);
193 }
194
drawVLine(SkCanvas * canvas,SkScalar x,const SkPaint & paint)195 static void drawVLine(SkCanvas* canvas, SkScalar x, const SkPaint& paint) {
196 canvas->drawLine(x, -999, x, 999, paint);
197 }
198
drawHLine(SkCanvas * canvas,SkScalar y,const SkPaint & paint)199 static void drawHLine(SkCanvas* canvas, SkScalar y, const SkPaint& paint) {
200 canvas->drawLine(-999, y, 999, y, paint);
201 }
202
onDrawContent(SkCanvas * canvas)203 virtual void onDrawContent(SkCanvas* canvas) {
204 SkMSec now = SampleCode::GetAnimTime();
205 if (fNow != now) {
206 fNow = now;
207 this->randPts();
208 this->inval(NULL);
209 }
210
211 // fProcIndex = test0(fPts, &fClip);
212
213 SkPaint paint, paint1;
214
215 drawVLine(canvas, fClip.fLeft + SK_ScalarHalf, paint);
216 drawVLine(canvas, fClip.fRight - SK_ScalarHalf, paint);
217 drawHLine(canvas, fClip.fTop + SK_ScalarHalf, paint);
218 drawHLine(canvas, fClip.fBottom - SK_ScalarHalf, paint);
219
220 paint.setColor(SK_ColorLTGRAY);
221 canvas->drawRect(fClip, paint);
222
223 paint.setAntiAlias(true);
224 paint.setColor(SK_ColorBLUE);
225 paint.setStyle(SkPaint::kStroke_Style);
226 // paint.setStrokeWidth(SkIntToScalar(3));
227 paint.setStrokeCap(SkPaint::kRound_Cap);
228
229 paint1.setAntiAlias(true);
230 paint1.setColor(SK_ColorRED);
231 paint1.setStyle(SkPaint::kStroke_Style);
232 gProcs[fProcIndex](fPts, fClip, canvas, paint, paint1);
233 this->inval(NULL);
234 }
235
onFindClickHandler(SkScalar x,SkScalar y)236 virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) {
237 // fProcIndex = (fProcIndex + 1) % SK_ARRAY_COUNT(gProcs);
238 if (x < 50 && y < 50) {
239 this->randPts();
240 }
241 this->inval(NULL);
242 return NULL;
243 }
244
onClick(Click * click)245 virtual bool onClick(Click* click) {
246 return false;
247 }
248
249 private:
250 typedef SampleView INHERITED;
251 };
252
253 //////////////////////////////////////////////////////////////////////////////
254
MyFactory()255 static SkView* MyFactory() { return new LineClipperView; }
256 static SkViewRegister reg(MyFactory);
257
258