1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
|
#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkCornerPathEffect.h"
#include "SkCullPoints.h"
#include "SkGradientShader.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "SkRandom.h"
static void addbump(SkPath* path, const SkPoint pts[2], SkScalar bump)
{
SkVector tang;
tang.setLength(pts[1].fX - pts[0].fX, pts[1].fY - pts[0].fY, bump);
path->lineTo(SkScalarHalf(pts[0].fX + pts[1].fX) - tang.fY,
SkScalarHalf(pts[0].fY + pts[1].fY) + tang.fX);
path->lineTo(pts[1]);
}
static void subdivide(SkPath* path, SkScalar bump)
{
SkPath::Iter iter(*path, false);
SkPoint pts[4];
SkPath tmp;
for (;;)
switch (iter.next(pts)) {
case SkPath::kMove_Verb:
tmp.moveTo(pts[0]);
break;
case SkPath::kLine_Verb:
addbump(&tmp, pts, bump);
bump = -bump;
break;
case SkPath::kDone_Verb:
goto FINISH;
default:
break;
}
FINISH:
path->swap(tmp);
}
static SkIPoint* getpts(const SkPath& path, int* count)
{
SkPoint pts[4];
int n = 1;
SkIPoint* array;
{
SkPath::Iter iter(path, false);
for (;;)
switch (iter.next(pts)) {
case SkPath::kLine_Verb:
n += 1;
break;
case SkPath::kDone_Verb:
goto FINISHED;
default:
break;
}
}
FINISHED:
array = new SkIPoint[n];
n = 0;
{
SkPath::Iter iter(path, false);
for (;;)
switch (iter.next(pts)) {
case SkPath::kMove_Verb:
array[n++].set(SkScalarRound(pts[0].fX), SkScalarRound(pts[0].fY));
break;
case SkPath::kLine_Verb:
array[n++].set(SkScalarRound(pts[1].fX), SkScalarRound(pts[1].fY));
break;
case SkPath::kDone_Verb:
goto FINISHED2;
default:
break;
}
}
FINISHED2:
*count = n;
return array;
}
static SkScalar nextScalarRange(SkRandom& rand, SkScalar min, SkScalar max)
{
return min + SkScalarMul(rand.nextUScalar1(), max - min);
}
class CullView : public SkView {
public:
CullView()
{
fClip.set(0, 0, SkIntToScalar(160), SkIntToScalar(160));
SkRandom rand;
for (int i = 0; i < 50; i++) {
int x = nextScalarRange(rand, -fClip.width()*1, fClip.width()*2);
int y = nextScalarRange(rand, -fClip.height()*1, fClip.height()*2);
if (i == 0)
fPath.moveTo(x, y);
else
fPath.lineTo(x, y);
}
SkScalar bump = fClip.width()/8;
subdivide(&fPath, bump);
subdivide(&fPath, bump);
subdivide(&fPath, bump);
fPoints = getpts(fPath, &fPtCount);
}
virtual ~CullView()
{
delete[] fPoints;
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt)
{
if (SampleCode::TitleQ(*evt))
{
SampleCode::TitleR(evt, "Culling");
return true;
}
return this->INHERITED::onQuery(evt);
}
void drawBG(SkCanvas* canvas)
{
canvas->drawColor(0xFFDDDDDD);
#if 0
SkPaint paint;
paint.setAntiAliasOn(true);
paint.setTextSize(SkIntToScalar(20));
paint.setTypeface(SkTypeface::Create("serif", SkTypeface::kBoldItalic))->unref();
uint16_t text[20];
text[0] = 'H';
text[1] = 'i';
text[2] = ' ';
for (int i = 3; i < 20; i++)
text[i] = 0x3040 + i;
canvas->drawText16(text, 20, SkIntToScalar(20), SkIntToScalar(20), paint);
#endif
}
virtual void onDraw(SkCanvas* canvas)
{
this->drawBG(canvas);
SkAutoCanvasRestore ar(canvas, true);
canvas->translate( SkScalarHalf(this->width() - fClip.width()),
SkScalarHalf(this->height() - fClip.height()));
// canvas->scale(SK_Scalar1*3, SK_Scalar1*3, 0, 0);
SkPaint paint;
// paint.setAntiAliasOn(true);
paint.setStyle(SkPaint::kStroke_Style);
canvas->drawRect(fClip, paint);
#if 1
paint.setColor(0xFF555555);
paint.setStrokeWidth(SkIntToScalar(2));
// paint.setPathEffect(new SkCornerPathEffect(SkIntToScalar(30)))->unref();
canvas->drawPath(fPath, paint);
// paint.setPathEffect(NULL);
#endif
SkPath tmp;
SkIRect iclip;
fClip.round(&iclip);
SkCullPointsPath cpp(iclip, &tmp);
cpp.moveTo(fPoints[0].fX, fPoints[0].fY);
for (int i = 0; i < fPtCount; i++)
cpp.lineTo(fPoints[i].fX, fPoints[i].fY);
paint.setColor(SK_ColorRED);
paint.setStrokeWidth(SkIntToScalar(3));
paint.setStrokeJoin(SkPaint::kRound_Join);
canvas->drawPath(tmp, paint);
this->inval(NULL);
}
virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y)
{
return this->INHERITED::onFindClickHandler(x, y);
}
virtual bool onClick(Click* click)
{
return this->INHERITED::onClick(click);
}
private:
SkRect fClip;
SkIPoint* fPoints;
SkPath fPath;
int fPtCount;
typedef SkView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new CullView; }
static SkViewRegister reg(MyFactory);
|
