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
|
/*
* 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 "SkDashPathEffect.h"
#include "SkBuffer.h"
#include "SkPathMeasure.h"
static inline int is_even(int x) {
return (~x) << 31;
}
static SkScalar FindFirstInterval(const SkScalar intervals[], SkScalar phase,
int32_t* index) {
int i;
for (i = 0; phase > intervals[i]; i++) {
phase -= intervals[i];
}
*index = i;
return intervals[i] - phase;
}
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count,
SkScalar phase, bool scaleToFit)
: fScaleToFit(scaleToFit) {
SkASSERT(intervals);
SkASSERT(count > 1 && SkAlign2(count) == count);
fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
fCount = count;
SkScalar len = 0;
for (int i = 0; i < count; i++) {
SkASSERT(intervals[i] >= 0);
fIntervals[i] = intervals[i];
len += intervals[i];
}
fIntervalLength = len;
if (len > 0) { // we don't handle 0 length dash arrays
if (phase < 0) {
phase = -phase;
if (phase > len) {
phase = SkScalarMod(phase, len);
}
phase = len - phase;
} else if (phase >= len) {
phase = SkScalarMod(phase, len);
}
// got to watch out for values that might make us go out of bounds
if (!SkScalarIsFinite(phase) || !SkScalarIsFinite(len)) {
goto BAD_DASH;
}
SkASSERT(phase >= 0 && phase < len);
fInitialDashLength = FindFirstInterval(intervals, phase, &fInitialDashIndex);
SkASSERT(fInitialDashLength >= 0);
SkASSERT(fInitialDashIndex >= 0 && fInitialDashIndex < fCount);
} else {
BAD_DASH:
fInitialDashLength = -1; // signal bad dash intervals
}
}
SkDashPathEffect::~SkDashPathEffect() {
sk_free(fIntervals);
}
bool SkDashPathEffect::filterPath(SkPath* dst, const SkPath& src,
SkScalar* width) {
// we do nothing if the src wants to be filled, or if our dashlength is 0
if (*width < 0 || fInitialDashLength < 0) {
return false;
}
SkPathMeasure meas(src, false);
const SkScalar* intervals = fIntervals;
do {
bool skipFirstSegment = meas.isClosed();
bool addedSegment = false;
SkScalar length = meas.getLength();
int index = fInitialDashIndex;
SkScalar scale = SK_Scalar1;
if (fScaleToFit) {
if (fIntervalLength >= length) {
scale = SkScalarDiv(length, fIntervalLength);
} else {
SkScalar div = SkScalarDiv(length, fIntervalLength);
int n = SkScalarFloor(div);
scale = SkScalarDiv(length, n * fIntervalLength);
}
}
SkScalar distance = 0;
SkScalar dlen = SkScalarMul(fInitialDashLength, scale);
while (distance < length) {
SkASSERT(dlen >= 0);
addedSegment = false;
if (is_even(index) && dlen > 0 && !skipFirstSegment) {
addedSegment = true;
meas.getSegment(distance, distance + dlen, dst, true);
}
distance += dlen;
// clear this so we only respect it the first time around
skipFirstSegment = false;
// wrap around our intervals array if necessary
index += 1;
SkASSERT(index <= fCount);
if (index == fCount) {
index = 0;
}
// fetch our next dlen
dlen = SkScalarMul(intervals[index], scale);
}
// extend if we ended on a segment and we need to join up with the (skipped) initial segment
if (meas.isClosed() && is_even(fInitialDashIndex) &&
fInitialDashLength > 0) {
meas.getSegment(0, SkScalarMul(fInitialDashLength, scale), dst, !addedSegment);
}
} while (meas.nextContour());
return true;
}
SkFlattenable::Factory SkDashPathEffect::getFactory() {
return fInitialDashLength < 0 ? NULL : CreateProc;
}
void SkDashPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
SkASSERT(fInitialDashLength >= 0);
this->INHERITED::flatten(buffer);
buffer.write32(fCount);
buffer.write32(fInitialDashIndex);
buffer.writeScalar(fInitialDashLength);
buffer.writeScalar(fIntervalLength);
buffer.write32(fScaleToFit);
buffer.writeMul4(fIntervals, fCount * sizeof(fIntervals[0]));
}
SkFlattenable* SkDashPathEffect::CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkDashPathEffect, (buffer));
}
SkDashPathEffect::SkDashPathEffect(SkFlattenableReadBuffer& buffer) {
fCount = buffer.readS32();
fInitialDashIndex = buffer.readS32();
fInitialDashLength = buffer.readScalar();
fIntervalLength = buffer.readScalar();
fScaleToFit = (buffer.readS32() != 0);
fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * fCount);
buffer.read(fIntervals, fCount * sizeof(fIntervals[0]));
}
///////////////////////////////////////////////////////////////////////////////
SK_DEFINE_FLATTENABLE_REGISTRAR(SkDashPathEffect)
|