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
|
/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "Sk1DPathEffect.h"
#include "SkReadBuffer.h"
#include "SkWriteBuffer.h"
#include "SkPathMeasure.h"
#include "SkStrokeRec.h"
bool Sk1DPathEffect::filterPath(SkPath* dst, const SkPath& src,
SkStrokeRec*, const SkRect*) const {
SkPathMeasure meas(src, false);
do {
SkScalar length = meas.getLength();
SkScalar distance = this->begin(length);
while (distance < length) {
SkScalar delta = this->next(dst, distance, meas);
if (delta <= 0) {
break;
}
distance += delta;
}
} while (meas.nextContour());
return true;
}
///////////////////////////////////////////////////////////////////////////////
SkPath1DPathEffect::SkPath1DPathEffect(const SkPath& path, SkScalar advance,
SkScalar phase, Style style) : fPath(path)
{
SkASSERT(advance > 0 && !path.isEmpty());
// cleanup their phase parameter, inverting it so that it becomes an
// offset along the path (to match the interpretation in PostScript)
if (phase < 0) {
phase = -phase;
if (phase > advance) {
phase = SkScalarMod(phase, advance);
}
} else {
if (phase > advance) {
phase = SkScalarMod(phase, advance);
}
phase = advance - phase;
}
// now catch the edge case where phase == advance (within epsilon)
if (phase >= advance) {
phase = 0;
}
SkASSERT(phase >= 0);
fAdvance = advance;
fInitialOffset = phase;
if ((unsigned)style > kMorph_Style) {
SkDEBUGF(("SkPath1DPathEffect style enum out of range %d\n", style));
}
fStyle = style;
}
bool SkPath1DPathEffect::filterPath(SkPath* dst, const SkPath& src,
SkStrokeRec* rec, const SkRect* cullRect) const {
if (fAdvance > 0) {
rec->setFillStyle();
return this->INHERITED::filterPath(dst, src, rec, cullRect);
}
return false;
}
static bool morphpoints(SkPoint dst[], const SkPoint src[], int count,
SkPathMeasure& meas, SkScalar dist) {
for (int i = 0; i < count; i++) {
SkPoint pos;
SkVector tangent;
SkScalar sx = src[i].fX;
SkScalar sy = src[i].fY;
if (!meas.getPosTan(dist + sx, &pos, &tangent)) {
return false;
}
SkMatrix matrix;
SkPoint pt;
pt.set(sx, sy);
matrix.setSinCos(tangent.fY, tangent.fX, 0, 0);
matrix.preTranslate(-sx, 0);
matrix.postTranslate(pos.fX, pos.fY);
matrix.mapPoints(&dst[i], &pt, 1);
}
return true;
}
/* TODO
Need differentially more subdivisions when the follow-path is curvy. Not sure how to
determine that, but we need it. I guess a cheap answer is let the caller tell us,
but that seems like a cop-out. Another answer is to get Rob Johnson to figure it out.
*/
static void morphpath(SkPath* dst, const SkPath& src, SkPathMeasure& meas,
SkScalar dist) {
SkPath::Iter iter(src, false);
SkPoint srcP[4], dstP[3];
SkPath::Verb verb;
while ((verb = iter.next(srcP)) != SkPath::kDone_Verb) {
switch (verb) {
case SkPath::kMove_Verb:
if (morphpoints(dstP, srcP, 1, meas, dist)) {
dst->moveTo(dstP[0]);
}
break;
case SkPath::kLine_Verb:
srcP[2] = srcP[1];
srcP[1].set(SkScalarAve(srcP[0].fX, srcP[2].fX),
SkScalarAve(srcP[0].fY, srcP[2].fY));
// fall through to quad
case SkPath::kQuad_Verb:
if (morphpoints(dstP, &srcP[1], 2, meas, dist)) {
dst->quadTo(dstP[0], dstP[1]);
}
break;
case SkPath::kConic_Verb:
if (morphpoints(dstP, &srcP[1], 2, meas, dist)) {
dst->conicTo(dstP[0], dstP[1], iter.conicWeight());
}
break;
case SkPath::kCubic_Verb:
if (morphpoints(dstP, &srcP[1], 3, meas, dist)) {
dst->cubicTo(dstP[0], dstP[1], dstP[2]);
}
break;
case SkPath::kClose_Verb:
dst->close();
break;
default:
SkDEBUGFAIL("unknown verb");
break;
}
}
}
SkScalar SkPath1DPathEffect::begin(SkScalar contourLength) const {
return fInitialOffset;
}
sk_sp<SkFlattenable> SkPath1DPathEffect::CreateProc(SkReadBuffer& buffer) {
SkScalar advance = buffer.readScalar();
if (advance > 0) {
SkPath path;
buffer.readPath(&path);
SkScalar phase = buffer.readScalar();
Style style = (Style)buffer.readUInt();
return SkPath1DPathEffect::Make(path, advance, phase, style);
}
return nullptr;
}
void SkPath1DPathEffect::flatten(SkWriteBuffer& buffer) const {
buffer.writeScalar(fAdvance);
if (fAdvance > 0) {
buffer.writePath(fPath);
buffer.writeScalar(fInitialOffset);
buffer.writeUInt(fStyle);
}
}
SkScalar SkPath1DPathEffect::next(SkPath* dst, SkScalar distance,
SkPathMeasure& meas) const {
switch (fStyle) {
case kTranslate_Style: {
SkPoint pos;
if (meas.getPosTan(distance, &pos, nullptr)) {
dst->addPath(fPath, pos.fX, pos.fY);
}
} break;
case kRotate_Style: {
SkMatrix matrix;
if (meas.getMatrix(distance, &matrix)) {
dst->addPath(fPath, matrix);
}
} break;
case kMorph_Style:
morphpath(dst, fPath, meas, distance);
break;
default:
SkDEBUGFAIL("unknown Style enum");
break;
}
return fAdvance;
}
#ifndef SK_IGNORE_TO_STRING
void SkPath1DPathEffect::toString(SkString* str) const {
str->appendf("SkPath1DPathEffect: (");
// TODO: add path and style
str->appendf("advance: %.2f phase %.2f", fAdvance, fInitialOffset);
str->appendf(")");
}
#endif
///////////////////////////////////////////////////////////////////////////////////////////////////
sk_sp<SkPathEffect> SkPath1DPathEffect::Make(const SkPath& path, SkScalar advance, SkScalar phase,
Style style) {
if (advance <= 0 || !SkScalarIsFinite(advance) ||
!SkScalarIsFinite(phase) || path.isEmpty()) {
return nullptr;
}
return sk_sp<SkPathEffect>(new SkPath1DPathEffect(path, advance, phase, style));
}
|
