SkTableColorFilter.cpp revision a69b48c29dff7338c3dbc2f2262ef28719483be1 
1#include "SkColorPriv.h"
2#include "SkTableColorFilter.h"
3#include "SkUnPreMultiply.h"
4
5class SkTable_ColorFilter : public SkColorFilter {
6public:
7    SkTable_ColorFilter(const uint8_t tableA[], const uint8_t tableR[],
8                        const uint8_t tableG[], const uint8_t tableB[]) {
9        fFlags = 0;
10        uint8_t* dst = fStorage;
11        if (tableA) {
12            memcpy(dst, tableA, 256);
13            dst += 256;
14            fFlags |= kA_Flag;
15        }
16        if (tableR) {
17            memcpy(dst, tableR, 256);
18            dst += 256;
19            fFlags |= kR_Flag;
20        }
21        if (tableG) {
22            memcpy(dst, tableG, 256);
23            dst += 256;
24            fFlags |= kG_Flag;
25        }
26        if (tableB) {
27            memcpy(dst, tableB, 256);
28            fFlags |= kB_Flag;
29        }
30    }
31
32    virtual void filterSpan(const SkPMColor src[], int count,
33                            SkPMColor dst[]) SK_OVERRIDE;
34    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
35    virtual Factory getFactory() SK_OVERRIDE;
36
37    static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
38        return SkNEW_ARGS(SkTable_ColorFilter, (buffer));
39    }
40
41protected:
42    SkTable_ColorFilter(SkFlattenableReadBuffer& buffer);
43
44private:
45    enum {
46        kA_Flag = 1 << 0,
47        kR_Flag = 1 << 1,
48        kG_Flag = 1 << 2,
49        kB_Flag = 1 << 3,
50    };
51    uint8_t fStorage[256 * 4];
52    unsigned fFlags;
53
54    typedef SkColorFilter INHERITED;
55};
56
57static const uint8_t gIdentityTable[] = {
58    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
59    0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
60    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
61    0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
62    0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
63    0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
64    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
65    0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
66    0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
67    0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F,
68    0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
69    0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
70    0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
71    0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
72    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
73    0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
74    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
75    0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F,
76    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
77    0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F,
78    0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7,
79    0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF,
80    0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7,
81    0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF,
82    0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7,
83    0xC8, 0xC9, 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF,
84    0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7,
85    0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF,
86    0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7,
87    0xE8, 0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF,
88    0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
89    0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF
90};
91
92void SkTable_ColorFilter::filterSpan(const SkPMColor src[], int count,
93                                     SkPMColor dst[]) {
94    const uint8_t* table = fStorage;
95    const uint8_t* tableA = gIdentityTable;
96    const uint8_t* tableR = gIdentityTable;
97    const uint8_t* tableG = gIdentityTable;
98    const uint8_t* tableB = gIdentityTable;
99    if (fFlags & kA_Flag) {
100        tableA = table; table += 256;
101    }
102    if (fFlags & kR_Flag) {
103        tableR = table; table += 256;
104    }
105    if (fFlags & kG_Flag) {
106        tableG = table; table += 256;
107    }
108    if (fFlags & kB_Flag) {
109        tableB = table;
110    }
111
112    const SkUnPreMultiply::Scale* scaleTable = SkUnPreMultiply::GetScaleTable();
113    for (int i = 0; i < count; ++i) {
114        SkPMColor c = src[i];
115        unsigned a, r, g, b;
116        if (0 == c) {
117            a = r = g = b = 0;
118        } else {
119            a = SkGetPackedA32(c);
120            r = SkGetPackedR32(c);
121            g = SkGetPackedG32(c);
122            b = SkGetPackedB32(c);
123
124            if (a < 255) {
125                SkUnPreMultiply::Scale scale = scaleTable[a];
126                r = SkUnPreMultiply::ApplyScale(scale, r);
127                g = SkUnPreMultiply::ApplyScale(scale, g);
128                b = SkUnPreMultiply::ApplyScale(scale, b);
129            }
130        }
131        dst[i] = SkPremultiplyARGBInline(tableA[a], tableR[r],
132                                         tableG[g], tableB[b]);
133    }
134}
135
136SkFlattenable::Factory SkTable_ColorFilter::getFactory() {
137    return CreateProc;
138}
139
140static const uint8_t gCountNibBits[] = {
141    0, 1, 1, 2,
142    1, 2, 2, 3,
143    1, 2, 2, 3,
144    2, 3, 3, 4
145};
146
147#include "SkPackBits.h"
148
149void SkTable_ColorFilter::flatten(SkFlattenableWriteBuffer& buffer) {
150    this->INHERITED::flatten(buffer);
151
152    uint8_t storage[5*256];
153    int count = gCountNibBits[fFlags & 0xF];
154    size_t size = SkPackBits::Pack8(fStorage, count * 256, storage);
155    SkASSERT(size <= sizeof(storage));
156
157//    SkDebugf("raw %d packed %d\n", count * 256, size);
158
159    buffer.writeInt(fFlags);
160    buffer.writeInt(size);
161    buffer.write(storage, size);
162}
163
164SkTable_ColorFilter::SkTable_ColorFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
165    uint8_t storage[5*256];
166
167    fFlags = buffer.readInt();
168    size_t size = buffer.readInt();
169    buffer.read(storage, size);
170
171    size_t raw = SkPackBits::Unpack8(storage, size, fStorage);
172
173    SkASSERT(raw <= sizeof(fStorage));
174    int count = gCountNibBits[fFlags & 0xF];
175    SkASSERT(raw == count * 256);
176}
177
178///////////////////////////////////////////////////////////////////////////////
179
180#ifdef SK_CPU_BENDIAN
181#else
182    #define SK_A32_INDEX    (3 - (SK_A32_SHIFT >> 3))
183    #define SK_R32_INDEX    (3 - (SK_R32_SHIFT >> 3))
184    #define SK_G32_INDEX    (3 - (SK_G32_SHIFT >> 3))
185    #define SK_B32_INDEX    (3 - (SK_B32_SHIFT >> 3))
186#endif
187
188///////////////////////////////////////////////////////////////////////////////
189
190SkColorFilter* SkTableColorFilter::Create(const uint8_t table[256]) {
191    return SkNEW_ARGS(SkTable_ColorFilter, (table, table, table, table));
192}
193
194SkColorFilter* SkTableColorFilter::CreateARGB(const uint8_t tableA[256],
195                                              const uint8_t tableR[256],
196                                              const uint8_t tableG[256],
197                                              const uint8_t tableB[256]) {
198    return SkNEW_ARGS(SkTable_ColorFilter, (tableA, tableR, tableG, tableB));
199}
200