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
|
/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef SkPathMeasure_DEFINED
#define SkPathMeasure_DEFINED
#include "SkPath.h"
#include "SkTDArray.h"
class SkPathMeasure : SkNoncopyable {
public:
SkPathMeasure();
/** Initialize the pathmeasure with the specified path. The path must remain valid
for the lifetime of the measure object, or until setPath() is called with
a different path (or null), since the measure object keeps a pointer to the
path object (does not copy its data).
*/
SkPathMeasure(const SkPath& path, bool forceClosed);
~SkPathMeasure();
/** Reset the pathmeasure with the specified path. The path must remain valid
for the lifetime of the measure object, or until setPath() is called with
a different path (or null), since the measure object keeps a pointer to the
path object (does not copy its data).
*/
void setPath(const SkPath*, bool forceClosed);
/** Return the total length of the current contour, or 0 if no path
is associated (e.g. resetPath(null))
*/
SkScalar getLength();
/** Pins distance to 0 <= distance <= getLength(), and then computes
the corresponding position and tangent.
Returns false if there is no path, or a zero-length path was specified, in which case
position and tangent are unchanged.
*/
bool getPosTan(SkScalar distance, SkPoint* position, SkVector* tangent);
enum MatrixFlags {
kGetPosition_MatrixFlag = 0x01,
kGetTangent_MatrixFlag = 0x02,
kGetPosAndTan_MatrixFlag = kGetPosition_MatrixFlag | kGetTangent_MatrixFlag
};
/** Pins distance to 0 <= distance <= getLength(), and then computes
the corresponding matrix (by calling getPosTan).
Returns false if there is no path, or a zero-length path was specified, in which case
matrix is unchanged.
*/
bool getMatrix(SkScalar distance, SkMatrix* matrix, MatrixFlags flags = kGetPosAndTan_MatrixFlag);
/** Given a start and stop distance, return in dst the intervening segment(s).
If the segment is zero-length, return false, else return true.
startD and stopD are pinned to legal values (0..getLength()). If startD <= stopD
then return false (and leave dst untouched).
Begin the segment with a moveTo if startWithMoveTo is true
*/
bool getSegment(SkScalar startD, SkScalar stopD, SkPath* dst, bool startWithMoveTo);
/** Return true if the current contour is closed()
*/
bool isClosed();
/** Move to the next contour in the path. Return true if one exists, or false if
we're done with the path.
*/
bool nextContour();
#ifdef SK_DEBUG
void dump();
#endif
private:
SkPath::Iter fIter;
const SkPath* fPath;
SkScalar fLength; // relative to the current contour
int fFirstPtIndex; // relative to the current contour
bool fIsClosed; // relative to the current contour
bool fForceClosed;
struct Segment {
SkScalar fDistance; // total distance up to this point
unsigned fPtIndex : 15;
unsigned fTValue : 15;
unsigned fType : 2;
SkScalar getScalarT() const;
};
SkTDArray<Segment> fSegments;
static const Segment* NextSegment(const Segment*);
void buildSegments();
SkScalar compute_quad_segs(const SkPoint pts[3], SkScalar distance,
int mint, int maxt, int ptIndex);
SkScalar compute_cubic_segs(const SkPoint pts[3], SkScalar distance,
int mint, int maxt, int ptIndex);
const Segment* distanceToSegment(SkScalar distance, SkScalar* t);
};
#endif
|
