SamplePath.cpp revision f7834221ac5342a3446b9b299398ea3ff7976946 
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
9#include "SampleCode.h"
10#include "SkAnimTimer.h"
11#include "SkView.h"
12#include "SkCanvas.h"
13#include "SkGradientShader.h"
14#include "SkGraphics.h"
15#include "SkImageDecoder.h"
16#include "SkPath.h"
17#include "SkRegion.h"
18#include "SkShader.h"
19#include "SkUtils.h"
20#include "SkXfermode.h"
21#include "SkColorPriv.h"
22#include "SkColorFilter.h"
23#include "SkParsePath.h"
24#include "SkTime.h"
25#include "SkTypeface.h"
26
27#include "SkGeometry.h"
28
29// http://code.google.com/p/skia/issues/detail?id=32
30static void test_cubic() {
31    SkPoint src[4] = {
32        { 556.25000f, 523.03003f },
33        { 556.23999f, 522.96002f },
34        { 556.21997f, 522.89001f },
35        { 556.21997f, 522.82001f }
36    };
37    SkPoint dst[11];
38    dst[10].set(42, -42);   // one past the end, that we don't clobber these
39    SkScalar tval[] = { 0.33333334f, 0.99999994f };
40
41    SkChopCubicAt(src, dst, tval, 2);
42
43#if 0
44    for (int i = 0; i < 11; i++) {
45        SkDebugf("--- %d [%g %g]\n", i, dst[i].fX, dst[i].fY);
46    }
47#endif
48}
49
50static void test_cubic2() {
51    const char* str = "M2242 -590088L-377758 9.94099e+07L-377758 9.94099e+07L2242 -590088Z";
52    SkPath path;
53    SkParsePath::FromSVGString(str, &path);
54
55    {
56#ifdef SK_BUILD_FOR_WIN
57        // windows doesn't have strtof
58        float x = (float)strtod("9.94099e+07", NULL);
59#else
60        float x = strtof("9.94099e+07", NULL);
61#endif
62        int ix = (int)x;
63        int fx = (int)(x * 65536);
64        int ffx = SkScalarToFixed(x);
65        SkDebugf("%g %x %x %x\n", x, ix, fx, ffx);
66
67        SkRect r = path.getBounds();
68        SkIRect ir;
69        r.round(&ir);
70        SkDebugf("[%g %g %g %g] [%x %x %x %x]\n",
71                SkScalarToDouble(r.fLeft), SkScalarToDouble(r.fTop),
72                SkScalarToDouble(r.fRight), SkScalarToDouble(r.fBottom),
73                ir.fLeft, ir.fTop, ir.fRight, ir.fBottom);
74    }
75
76    SkBitmap bitmap;
77    bitmap.allocN32Pixels(300, 200);
78
79    SkCanvas canvas(bitmap);
80    SkPaint paint;
81    paint.setAntiAlias(true);
82    canvas.drawPath(path, paint);
83}
84
85class PathView : public SampleView {
86    SkScalar fPrevSecs;
87public:
88    SkScalar fDStroke, fStroke, fMinStroke, fMaxStroke;
89    SkPath fPath[6];
90    bool fShowHairline;
91    bool fOnce;
92
93    PathView() {
94        fPrevSecs = 0;
95        fOnce = false;
96    }
97
98    void init() {
99        if (fOnce) {
100            return;
101        }
102        fOnce = true;
103
104        test_cubic();
105        test_cubic2();
106
107        fShowHairline = false;
108
109        fDStroke = 1;
110        fStroke = 10;
111        fMinStroke = 10;
112        fMaxStroke = 180;
113
114        const SkScalar V = 85;
115
116        fPath[0].moveTo(40, 70);
117        fPath[0].lineTo(70, 70 + SK_ScalarHalf);
118        fPath[0].lineTo(110, 70);
119
120        fPath[1].moveTo(40, 70);
121        fPath[1].lineTo(70, 70 - SK_ScalarHalf);
122        fPath[1].lineTo(110, 70);
123
124        fPath[2].moveTo(V, V);
125        fPath[2].lineTo(50, V);
126        fPath[2].lineTo(50, 50);
127
128        fPath[3].moveTo(50, 50);
129        fPath[3].lineTo(50, V);
130        fPath[3].lineTo(V, V);
131
132        fPath[4].moveTo(50, 50);
133        fPath[4].lineTo(50, V);
134        fPath[4].lineTo(52, 50);
135
136        fPath[5].moveTo(52, 50);
137        fPath[5].lineTo(50, V);
138        fPath[5].lineTo(50, 50);
139
140        this->setBGColor(0xFFDDDDDD);
141    }
142
143protected:
144    // overrides from SkEventSink
145    bool onQuery(SkEvent* evt) override {
146        if (SampleCode::TitleQ(*evt)) {
147            SampleCode::TitleR(evt, "Paths");
148            return true;
149        }
150        return this->INHERITED::onQuery(evt);
151    }
152
153    void drawPath(SkCanvas* canvas, const SkPath& path, SkPaint::Join j) {
154        SkPaint paint;
155
156        paint.setAntiAlias(true);
157        paint.setStyle(SkPaint::kStroke_Style);
158        paint.setStrokeJoin(j);
159        paint.setStrokeWidth(fStroke);
160
161        if (fShowHairline) {
162            SkPath  fill;
163
164            paint.getFillPath(path, &fill);
165            paint.setStrokeWidth(0);
166            canvas->drawPath(fill, paint);
167        } else {
168            canvas->drawPath(path, paint);
169        }
170
171        paint.setColor(SK_ColorRED);
172        paint.setStrokeWidth(0);
173        canvas->drawPath(path, paint);
174    }
175
176    void onDrawContent(SkCanvas* canvas) override {
177        this->init();
178        canvas->translate(50, 50);
179
180        static const SkPaint::Join gJoins[] = {
181            SkPaint::kBevel_Join,
182            SkPaint::kMiter_Join,
183            SkPaint::kRound_Join
184        };
185
186        for (size_t i = 0; i < SK_ARRAY_COUNT(gJoins); i++) {
187            canvas->save();
188            for (size_t j = 0; j < SK_ARRAY_COUNT(fPath); j++) {
189                this->drawPath(canvas, fPath[j], gJoins[i]);
190                canvas->translate(200, 0);
191            }
192            canvas->restore();
193
194            canvas->translate(0, 200);
195        }
196    }
197
198    bool onAnimate(const SkAnimTimer& timer) override {
199        SkScalar currSecs = timer.scaled(100);
200        SkScalar delta = currSecs - fPrevSecs;
201        fPrevSecs = currSecs;
202
203        fStroke += fDStroke * delta;
204        if (fStroke > fMaxStroke || fStroke < fMinStroke) {
205            fDStroke = -fDStroke;
206        }
207        return true;
208    }
209
210    SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
211        fShowHairline = !fShowHairline;
212        this->inval(NULL);
213        return this->INHERITED::onFindClickHandler(x, y, modi);
214    }
215
216private:
217    typedef SampleView INHERITED;
218};
219DEF_SAMPLE( return new PathView; )
220
221//////////////////////////////////////////////////////////////////////////////
222
223#include "SkArcToPathEffect.h"
224#include "SkCornerPathEffect.h"
225#include "SkRandom.h"
226
227class ArcToView : public SampleView {
228    bool fDoFrame, fDoArcTo, fDoCorner, fDoConic;
229    SkPaint fPtsPaint, fArcToPaint, fSkeletonPaint, fCornerPaint;
230public:
231    enum {
232        N = 4
233    };
234    SkPoint fPts[N];
235
236    ArcToView()
237        : fDoFrame(false), fDoArcTo(false), fDoCorner(false), fDoConic(false)
238    {
239        SkRandom rand;
240        for (int i = 0; i < N; ++i) {
241            fPts[i].fX = 20 + rand.nextUScalar1() * 640;
242            fPts[i].fY = 20 + rand.nextUScalar1() * 480;
243        }
244
245        const SkScalar rad = 50;
246
247        fPtsPaint.setAntiAlias(true);
248        fPtsPaint.setStrokeWidth(15);
249        fPtsPaint.setStrokeCap(SkPaint::kRound_Cap);
250
251        fArcToPaint.setAntiAlias(true);
252        fArcToPaint.setStyle(SkPaint::kStroke_Style);
253        fArcToPaint.setStrokeWidth(9);
254        fArcToPaint.setColor(0x800000FF);
255        fArcToPaint.setPathEffect(SkArcToPathEffect::Create(rad))->unref();
256
257        fCornerPaint.setAntiAlias(true);
258        fCornerPaint.setStyle(SkPaint::kStroke_Style);
259        fCornerPaint.setStrokeWidth(13);
260        fCornerPaint.setColor(SK_ColorGREEN);
261        fCornerPaint.setPathEffect(SkCornerPathEffect::Create(rad*2))->unref();
262
263        fSkeletonPaint.setAntiAlias(true);
264        fSkeletonPaint.setStyle(SkPaint::kStroke_Style);
265        fSkeletonPaint.setColor(SK_ColorRED);
266    }
267
268    void toggle(bool& value) {
269        value = !value;
270        this->inval(NULL);
271    }
272
273protected:
274    // overrides from SkEventSink
275    bool onQuery(SkEvent* evt) override {
276        if (SampleCode::TitleQ(*evt)) {
277            SampleCode::TitleR(evt, "ArcTo");
278            return true;
279        }
280        SkUnichar uni;
281        if (SampleCode::CharQ(*evt, &uni)) {
282            switch (uni) {
283                case '1': this->toggle(fDoFrame); return true;
284                case '2': this->toggle(fDoArcTo); return true;
285                case '3': this->toggle(fDoCorner); return true;
286                case '4': this->toggle(fDoConic); return true;
287                default: break;
288            }
289        }
290        return this->INHERITED::onQuery(evt);
291    }
292
293    void makePath(SkPath* path) {
294        path->moveTo(fPts[0]);
295        for (int i = 1; i < N; ++i) {
296            path->lineTo(fPts[i]);
297        }
298        if (!fDoFrame) {
299            path->close();
300        }
301    }
302
303    void onDrawContent(SkCanvas* canvas) override {
304        canvas->drawPoints(SkCanvas::kPoints_PointMode, N, fPts, fPtsPaint);
305
306        SkPath path;
307        this->makePath(&path);
308
309        if (fDoCorner) {
310            canvas->drawPath(path, fCornerPaint);
311        }
312        if (fDoArcTo) {
313            canvas->drawPath(path, fArcToPaint);
314        }
315
316        canvas->drawPath(path, fSkeletonPaint);
317    }
318
319    bool onClick(Click* click) override {
320        int32_t index;
321        if (click->fMeta.findS32("index", &index)) {
322            SkASSERT((unsigned)index < N);
323            fPts[index] = click->fCurr;
324            this->inval(NULL);
325            return true;
326        }
327        return false;
328    }
329
330    SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
331        const SkScalar tol = 4;
332        const SkRect r = SkRect::MakeXYWH(x - tol, y - tol, tol * 2, tol * 2);
333        for (int i = 0; i < N; ++i) {
334            if (r.intersects(SkRect::MakeXYWH(fPts[i].fX, fPts[i].fY, 1, 1))) {
335                Click* click = new Click(this);
336                click->fMeta.setS32("index", i);
337                return click;
338            }
339        }
340        return this->INHERITED::onFindClickHandler(x, y, modi);
341    }
342
343private:
344    typedef SampleView INHERITED;
345};
346DEF_SAMPLE( return new ArcToView; )
347
348