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
|
/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkRecordPattern_DEFINED
#define SkRecordPattern_DEFINED
#include "SkRecord.h"
#include "SkTLogic.h"
namespace SkRecords {
// First, some matchers. These match a single command in the SkRecord,
// and may hang onto some data from it. If so, you can get the data by calling .get().
// Matches a command of type T, and stores that command.
template <typename T>
class Is {
public:
Is() : fPtr(nullptr) {}
typedef T type;
type* get() { return fPtr; }
bool operator()(T* ptr) {
fPtr = ptr;
return true;
}
template <typename U>
bool operator()(U*) {
fPtr = nullptr;
return false;
}
private:
type* fPtr;
};
// Matches any command that draws, and stores its paint.
class IsDraw {
public:
IsDraw() : fPaint(nullptr) {}
typedef SkPaint type;
type* get() { return fPaint; }
template <typename T>
SK_WHEN((T::kTags & kDrawWithPaint_Tag) == kDrawWithPaint_Tag, bool) operator()(T* draw) {
fPaint = AsPtr(draw->paint);
return true;
}
template <typename T>
SK_WHEN((T::kTags & kDrawWithPaint_Tag) == kDraw_Tag, bool) operator()(T* draw) {
fPaint = nullptr;
return true;
}
template <typename T>
SK_WHEN(!(T::kTags & kDraw_Tag), bool) operator()(T* draw) {
fPaint = nullptr;
return false;
}
private:
// Abstracts away whether the paint is always part of the command or optional.
template <typename T> static T* AsPtr(SkRecords::Optional<T>& x) { return x; }
template <typename T> static T* AsPtr(T& x) { return &x; }
type* fPaint;
};
// Matches if Matcher doesn't. Stores nothing.
template <typename Matcher>
struct Not {
template <typename T>
bool operator()(T* ptr) { return !Matcher()(ptr); }
};
// Matches if any of First or Rest... does. Stores nothing.
template <typename First, typename... Rest>
struct Or {
template <typename T>
bool operator()(T* ptr) { return First()(ptr) || Or<Rest...>()(ptr); }
};
template <typename First>
struct Or<First> {
template <typename T>
bool operator()(T* ptr) { return First()(ptr); }
};
// Greedy is a special matcher that greedily matches Matcher 0 or more times. Stores nothing.
template <typename Matcher>
struct Greedy {
template <typename T>
bool operator()(T* ptr) { return Matcher()(ptr); }
};
// Pattern matches each of its matchers in order.
//
// This is the main entry point to pattern matching, and so provides a couple of extra API bits:
// - search scans through the record to look for matches;
// - first, second, third, ... return the data stored by their respective matchers in the pattern.
template <typename... Matchers> class Pattern;
template <> class Pattern<> {
public:
// Bottoms out recursion. Just return whatever i the front decided on.
int match(SkRecord*, int i) { return i; }
};
template <typename First, typename... Rest>
class Pattern<First, Rest...> {
public:
// If this pattern matches the SkRecord starting from i,
// return the index just past the end of the pattern, otherwise return 0.
SK_ALWAYS_INLINE int match(SkRecord* record, int i) {
i = this->matchFirst(&fFirst, record, i);
return i > 0 ? fRest.match(record, i) : 0;
}
// Starting from *end, walk through the SkRecord to find the first span matching this pattern.
// If there is no such span, return false. If there is, return true and set [*begin, *end).
SK_ALWAYS_INLINE bool search(SkRecord* record, int* begin, int* end) {
for (*begin = *end; *begin < record->count(); ++(*begin)) {
*end = this->match(record, *begin);
if (*end != 0) {
return true;
}
}
return false;
}
// TODO: some sort of smart get<i>()
template <typename T> T* first() { return fFirst.get(); }
template <typename T> T* second() { return fRest.template first<T>(); }
template <typename T> T* third() { return fRest.template second<T>(); }
template <typename T> T* fourth() { return fRest.template third<T>(); }
private:
// If first isn't a Greedy, try to match at i once.
template <typename T>
int matchFirst(T* first, SkRecord* record, int i) {
if (i < record->count()) {
if (record->mutate(i, *first)) {
return i+1;
}
}
return 0;
}
// If first is a Greedy, walk i until it doesn't match.
template <typename T>
int matchFirst(Greedy<T>* first, SkRecord* record, int i) {
while (i < record->count()) {
if (!record->mutate(i, *first)) {
return i;
}
i++;
}
return 0;
}
First fFirst;
Pattern<Rest...> fRest;
};
} // namespace SkRecords
#endif//SkRecordPattern_DEFINED
|
