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
|
/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkCoverageDelta_DEFINED
#define SkCoverageDelta_DEFINED
#include "SkArenaAlloc.h"
#include "SkFixed.h"
#include "SkMask.h"
#include "SkTSort.h"
#include "SkUtils.h"
// Future todo: maybe we can make fX and fDelta 16-bit long to speed it up a little bit.
struct SkCoverageDelta {
int fX; // the y coordinate will be implied in SkCoverageDeltaList
SkFixed fDelta; // the amount that the alpha changed
// Sort according to fX
bool operator<(const SkCoverageDelta& other) const {
return fX < other.fX;
}
};
// All the arguments needed for SkBlitter::blitAntiRect
struct SkAntiRect {
int fX;
int fY;
int fWidth;
int fHeight;
SkAlpha fLeftAlpha;
SkAlpha fRightAlpha;
};
// A list of SkCoverageDelta with y from top() to bottom().
// For each row y, there are count(y) number of deltas.
// You can ask whether they are sorted or not by sorted(y), and you can sort them by sort(y).
// Once sorted, getDelta(y, i) should return the i-th leftmost delta on row y.
class SkCoverageDeltaList {
public:
// We can store INIT_ROW_SIZE deltas per row (i.e., per y-scanline) initially.
#ifdef GOOGLE3
static constexpr int INIT_ROW_SIZE = 8; // google3 has 16k stack limit; so we make it small
#else
static constexpr int INIT_ROW_SIZE = 32;
#endif
SkCoverageDeltaList(SkArenaAlloc* alloc, int top, int bottom, bool forceRLE);
int top() const { return fTop; }
int bottom() const { return fBottom; }
bool forceRLE() const { return fForceRLE; }
int count(int y) const { this->checkY(y); return fCounts[y]; }
bool sorted(int y) const { this->checkY(y); return fSorted[y]; }
SK_ALWAYS_INLINE void addDelta(int x, int y, SkFixed delta) { this->push_back(y, {x, delta}); }
SK_ALWAYS_INLINE const SkCoverageDelta& getDelta(int y, int i) const {
this->checkY(y);
SkASSERT(i < fCounts[y]);
return fRows[y][i];
}
// It might be better to sort right before blitting to make the memory hot
void sort(int y) {
this->checkY(y);
if (!fSorted[y]) {
SkTQSort(fRows[y], fRows[y] + fCounts[y] - 1);
fSorted[y] = true;
}
}
const SkAntiRect& getAntiRect() const { return fAntiRect; }
void setAntiRect(int x, int y, int width, int height,
SkAlpha leftAlpha, SkAlpha rightAlpha) {
fAntiRect = {x, y, width, height, leftAlpha, rightAlpha};
}
private:
SkArenaAlloc* fAlloc;
SkCoverageDelta** fRows;
bool* fSorted;
int* fCounts;
int* fMaxCounts;
int fTop;
int fBottom;
SkAntiRect fAntiRect;
bool fForceRLE;
void checkY(int y) const { SkASSERT(y >= fTop && y < fBottom); }
SK_ALWAYS_INLINE void push_back(int y, const SkCoverageDelta& delta) {
this->checkY(y);
if (fCounts[y] == fMaxCounts[y]) {
fMaxCounts[y] *= 4;
SkCoverageDelta* newRow = fAlloc->makeArrayDefault<SkCoverageDelta>(fMaxCounts[y]);
memcpy(newRow, fRows[y], sizeof(SkCoverageDelta) * fCounts[y]);
fRows[y] = newRow;
}
SkASSERT(fCounts[y] < fMaxCounts[y]);
fRows[y][fCounts[y]++] = delta;
fSorted[y] = fSorted[y] && (fCounts[y] == 1 || delta.fX >= fRows[y][fCounts[y] - 2].fX);
}
};
class SkCoverageDeltaMask {
public:
// 1 for precision error, 1 for boundary delta (e.g., -SK_Fixed1 at fBounds.fRight + 1)
static constexpr int PADDING = 2;
static constexpr int SIMD_WIDTH = 8;
static constexpr int SUITABLE_WIDTH = 32;
#ifdef GOOGLE3
static constexpr int MAX_MASK_SIZE = 1024; // G3 has 16k stack limit based on -fstack-usage
#else
static constexpr int MAX_MASK_SIZE = 2048;
#endif
static constexpr int MAX_SIZE = MAX_MASK_SIZE * (sizeof(SkFixed) + sizeof(SkAlpha));
// Expand PADDING on both sides, and make it a multiple of SIMD_WIDTH
static int ExpandWidth(int width);
static bool CanHandle(const SkIRect& bounds); // whether bounds fits into MAX_MASK_SIZE
static bool Suitable(const SkIRect& bounds); // CanHandle(bounds) && width <= SUITABLE_WIDTH
SkCoverageDeltaMask(SkArenaAlloc* alloc, const SkIRect& bounds);
int top() const { return fBounds.fTop; }
int bottom() const { return fBounds.fBottom; }
SkAlpha* getMask() { return fMask; }
const SkIRect& getBounds() const { return fBounds; }
SK_ALWAYS_INLINE void addDelta (int x, int y, SkFixed delta) { this->delta(x, y) += delta; }
SK_ALWAYS_INLINE SkFixed& delta (int x, int y) {
this->checkX(x);
this->checkY(y);
return fDeltas[this->index(x, y)];
}
void setAntiRect(int x, int y, int width, int height,
SkAlpha leftAlpha, SkAlpha rightAlpha) {
fAntiRect = {x, y, width, height, leftAlpha, rightAlpha};
}
SkMask prepareSkMask() {
SkMask mask;
mask.fImage = fMask;
mask.fBounds = fBounds;
mask.fRowBytes = fBounds.width();
mask.fFormat = SkMask::kA8_Format;
return mask;
}
void convertCoverageToAlpha(bool isEvenOdd, bool isInverse, bool isConvex);
private:
SkIRect fBounds;
SkFixed* fDeltaStorage;
SkFixed* fDeltas;
SkAlpha* fMask;
int fExpandedWidth;
SkAntiRect fAntiRect;
SK_ALWAYS_INLINE int index(int x, int y) const { return y * fExpandedWidth + x; }
void checkY(int y) const { SkASSERT(y >= fBounds.fTop && y < fBounds.fBottom); }
void checkX(int x) const {
SkASSERT(x >= fBounds.fLeft - PADDING && x < fBounds.fRight + PADDING);
}
};
static SK_ALWAYS_INLINE SkAlpha CoverageToAlpha(SkFixed coverage, bool isEvenOdd, bool isInverse) {
SkAlpha result;
if (isEvenOdd) {
SkFixed mod17 = coverage & 0x1ffff;
SkFixed mod16 = coverage & 0xffff;
result = SkTPin(SkAbs32((mod16 << 1) - mod17) >> 8, 0, 255);
} else {
result = SkTPin(SkAbs32(coverage) >> 8, 0, 255);
}
return isInverse ? 255 - result : result;
}
template<typename T>
static SK_ALWAYS_INLINE T CoverageToAlpha(const T& coverage, bool isEvenOdd, bool isInverse) {
T t0(0), t255(255);
T result;
if (isEvenOdd) {
T mod17 = coverage & 0x1ffff;
T mod16 = coverage & 0xffff;
result = ((mod16 << 1) - mod17).abs() >> 8;
} else {
result = coverage.abs() >> 8;;
}
result = T::Min(result, t255);
result = T::Max(result, t0);
return isInverse ? 255 - result : result;
}
// For convex paths (including inverse mode), the coverage is guaranteed to be
// between [-SK_Fixed1, SK_Fixed1] so we can skip isEvenOdd and SkTPin.
static SK_ALWAYS_INLINE SkAlpha ConvexCoverageToAlpha(SkFixed coverage, bool isInverse) {
SkASSERT(coverage >= -SK_Fixed1 && coverage <= SK_Fixed1);
int result = SkAbs32(coverage) >> 8;
result -= (result >> 8); // 256 to 255
return isInverse ? 255 - result : result;
}
template<typename T>
static SK_ALWAYS_INLINE T ConvexCoverageToAlpha(const T& coverage, bool isInverse) {
// allTrue is not implemented
// SkASSERT((coverage >= 0).allTrue() && (coverage <= SK_Fixed1).allTrue());
T result = coverage.abs() >> 8;
result -= (result >> 8); // 256 to 255
return isInverse ? 255 - result : result;
}
#endif
|
