1 #include "SkTableMaskFilter.h"
2
SkTableMaskFilter()3 SkTableMaskFilter::SkTableMaskFilter() {
4 for (int i = 0; i < 256; i++) {
5 fTable[i] = i;
6 }
7 }
8
SkTableMaskFilter(const uint8_t table[256])9 SkTableMaskFilter::SkTableMaskFilter(const uint8_t table[256]) {
10 this->setTable(table);
11 }
12
~SkTableMaskFilter()13 SkTableMaskFilter::~SkTableMaskFilter() {}
14
setTable(const uint8_t table[256])15 void SkTableMaskFilter::setTable(const uint8_t table[256]) {
16 memcpy(fTable, table, 256);
17 }
18
filterMask(SkMask * dst,const SkMask & src,const SkMatrix &,SkIPoint * margin)19 bool SkTableMaskFilter::filterMask(SkMask* dst, const SkMask& src,
20 const SkMatrix&, SkIPoint* margin) {
21 if (src.fFormat != SkMask::kA8_Format) {
22 return false;
23 }
24
25 dst->fBounds = src.fBounds;
26 dst->fRowBytes = SkAlign4(dst->fBounds.width());
27 dst->fFormat = SkMask::kA8_Format;
28 dst->fImage = NULL;
29
30 if (src.fImage) {
31 dst->fImage = SkMask::AllocImage(dst->computeImageSize());
32
33 const uint8_t* srcP = src.fImage;
34 uint8_t* dstP = dst->fImage;
35 const uint8_t* table = fTable;
36 int dstWidth = dst->fBounds.width();
37 int extraZeros = dst->fRowBytes - dstWidth;
38
39 for (int y = dst->fBounds.height() - 1; y >= 0; --y) {
40 for (int x = dstWidth - 1; x >= 0; --x) {
41 dstP[x] = table[srcP[x]];
42 }
43 srcP += src.fRowBytes;
44 // we can't just inc dstP by rowbytes, because if it has any
45 // padding between its width and its rowbytes, we need to zero those
46 // so that the bitters can read those safely if that is faster for
47 // them
48 dstP += dstWidth;
49 for (int i = extraZeros - 1; i >= 0; --i) {
50 *dstP++ = 0;
51 }
52 }
53 }
54
55 if (margin) {
56 margin->set(0, 0);
57 }
58 return true;
59 }
60
getFormat()61 SkMask::Format SkTableMaskFilter::getFormat() {
62 return SkMask::kA8_Format;
63 }
64
flatten(SkFlattenableWriteBuffer & wb)65 void SkTableMaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
66 this->INHERITED::flatten(wb);
67 wb.writePad(fTable, 256);
68 }
69
SkTableMaskFilter(SkFlattenableReadBuffer & rb)70 SkTableMaskFilter::SkTableMaskFilter(SkFlattenableReadBuffer& rb)
71 : INHERITED(rb) {
72 rb.read(fTable, 256);
73 }
74
Factory(SkFlattenableReadBuffer & rb)75 SkFlattenable* SkTableMaskFilter::Factory(SkFlattenableReadBuffer& rb) {
76 return SkNEW_ARGS(SkTableMaskFilter, (rb));
77 }
78
getFactory()79 SkFlattenable::Factory SkTableMaskFilter::getFactory() {
80 return SkTableMaskFilter::Factory;
81 }
82
83 ///////////////////////////////////////////////////////////////////////////////
84
MakeGammaTable(uint8_t table[256],SkScalar gamma)85 void SkTableMaskFilter::MakeGammaTable(uint8_t table[256], SkScalar gamma) {
86 float x = 0;
87 const float dx = 1 / 255.0f;
88 for (int i = 0; i < 256; i++) {
89 table[i] = SkPin32(SkScalarRound(powf(x, gamma) * 255), 0, 255);
90 x += dx;
91 }
92 }
93
MakeClipTable(uint8_t table[256],uint8_t min,uint8_t max)94 void SkTableMaskFilter::MakeClipTable(uint8_t table[256], uint8_t min,
95 uint8_t max) {
96 if (0 == max) {
97 max = 1;
98 }
99 if (min >= max) {
100 min = max - 1;
101 }
102 SkASSERT(min < max);
103
104 SkFixed scale = (1 << 16) * 255 / (max - min);
105 memset(table, 0, min + 1);
106 for (int i = min + 1; i < max; i++) {
107 int value = SkFixedRound(scale * (i - min));
108 SkASSERT(value <= 255);
109 table[i] = value;
110 }
111 memset(table + max, 255, 256 - max);
112
113 #if 0
114 int j;
115 for (j = 0; j < 256; j++) {
116 if (table[j]) {
117 break;
118 }
119 }
120 SkDebugf("%d %d start [%d]", min, max, j);
121 for (; j < 256; j++) {
122 SkDebugf(" %d", table[j]);
123 }
124 SkDebugf("\n\n");
125 #endif
126 }
127
128