SkTableColorFilter.cpp revision f23f5f7f499b0dc885dc4e4544cdfc6ef6280d1e 
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        fBitmap = NULL;
10        fFlags = 0;
11
12        uint8_t* dst = fStorage;
13        if (tableA) {
14            memcpy(dst, tableA, 256);
15            dst += 256;
16            fFlags |= kA_Flag;
17        }
18        if (tableR) {
19            memcpy(dst, tableR, 256);
20            dst += 256;
21            fFlags |= kR_Flag;
22        }
23        if (tableG) {
24            memcpy(dst, tableG, 256);
25            dst += 256;
26            fFlags |= kG_Flag;
27        }
28        if (tableB) {
29            memcpy(dst, tableB, 256);
30            fFlags |= kB_Flag;
31        }
32    }
33
34    virtual bool asComponentTable(SkBitmap* table) SK_OVERRIDE;
35
36    virtual void filterSpan(const SkPMColor src[], int count,
37                            SkPMColor dst[]) SK_OVERRIDE;
38    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
39    virtual Factory getFactory() SK_OVERRIDE;
40
41    static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
42        return SkNEW_ARGS(SkTable_ColorFilter, (buffer));
43    }
44
45protected:
46    SkTable_ColorFilter(SkFlattenableReadBuffer& buffer);
47
48private:
49    SkBitmap* fBitmap;
50
51    enum {
52        kA_Flag = 1 << 0,
53        kR_Flag = 1 << 1,
54        kG_Flag = 1 << 2,
55        kB_Flag = 1 << 3,
56    };
57    uint8_t fStorage[256 * 4];
58    unsigned fFlags;
59
60    typedef SkColorFilter INHERITED;
61};
62
63static const uint8_t gIdentityTable[] = {
64    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
65    0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
66    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
67    0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
68    0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
69    0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
70    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
71    0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
72    0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
73    0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F,
74    0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
75    0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
76    0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
77    0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
78    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
79    0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
80    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
81    0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F,
82    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
83    0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F,
84    0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7,
85    0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF,
86    0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7,
87    0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF,
88    0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7,
89    0xC8, 0xC9, 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF,
90    0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7,
91    0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF,
92    0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7,
93    0xE8, 0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF,
94    0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
95    0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF
96};
97
98void SkTable_ColorFilter::filterSpan(const SkPMColor src[], int count,
99                                     SkPMColor dst[]) {
100    const uint8_t* table = fStorage;
101    const uint8_t* tableA = gIdentityTable;
102    const uint8_t* tableR = gIdentityTable;
103    const uint8_t* tableG = gIdentityTable;
104    const uint8_t* tableB = gIdentityTable;
105    if (fFlags & kA_Flag) {
106        tableA = table; table += 256;
107    }
108    if (fFlags & kR_Flag) {
109        tableR = table; table += 256;
110    }
111    if (fFlags & kG_Flag) {
112        tableG = table; table += 256;
113    }
114    if (fFlags & kB_Flag) {
115        tableB = table;
116    }
117
118    const SkUnPreMultiply::Scale* scaleTable = SkUnPreMultiply::GetScaleTable();
119    for (int i = 0; i < count; ++i) {
120        SkPMColor c = src[i];
121        unsigned a, r, g, b;
122        if (0 == c) {
123            a = r = g = b = 0;
124        } else {
125            a = SkGetPackedA32(c);
126            r = SkGetPackedR32(c);
127            g = SkGetPackedG32(c);
128            b = SkGetPackedB32(c);
129
130            if (a < 255) {
131                SkUnPreMultiply::Scale scale = scaleTable[a];
132                r = SkUnPreMultiply::ApplyScale(scale, r);
133                g = SkUnPreMultiply::ApplyScale(scale, g);
134                b = SkUnPreMultiply::ApplyScale(scale, b);
135            }
136        }
137        dst[i] = SkPremultiplyARGBInline(tableA[a], tableR[r],
138                                         tableG[g], tableB[b]);
139    }
140}
141
142SkFlattenable::Factory SkTable_ColorFilter::getFactory() {
143    return CreateProc;
144}
145
146static const uint8_t gCountNibBits[] = {
147    0, 1, 1, 2,
148    1, 2, 2, 3,
149    1, 2, 2, 3,
150    2, 3, 3, 4
151};
152
153#include "SkPackBits.h"
154
155void SkTable_ColorFilter::flatten(SkFlattenableWriteBuffer& buffer) {
156    this->INHERITED::flatten(buffer);
157
158    uint8_t storage[5*256];
159    int count = gCountNibBits[fFlags & 0xF];
160    size_t size = SkPackBits::Pack8(fStorage, count * 256, storage);
161    SkASSERT(size <= sizeof(storage));
162
163//    SkDebugf("raw %d packed %d\n", count * 256, size);
164
165    buffer.writeInt(fFlags);
166    buffer.writeInt(size);
167    buffer.write(storage, size);
168}
169
170SkTable_ColorFilter::SkTable_ColorFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
171    fBitmap = NULL;
172
173    uint8_t storage[5*256];
174
175    fFlags = buffer.readInt();
176    size_t size = buffer.readInt();
177    buffer.read(storage, size);
178
179    size_t raw = SkPackBits::Unpack8(storage, size, fStorage);
180
181    SkASSERT(raw <= sizeof(fStorage));
182    size_t count = gCountNibBits[fFlags & 0xF];
183    SkASSERT(raw == count * 256);
184}
185
186bool SkTable_ColorFilter::asComponentTable(SkBitmap* table) {
187    if (table) {
188        if (NULL == fBitmap) {
189            fBitmap = new SkBitmap;
190            fBitmap->setConfig(SkBitmap::kA8_Config, 256, 4, 256);
191            fBitmap->allocPixels();
192            memcpy(fBitmap->getAddr8(0, 0), fStorage, 256 * 4);
193        }
194        *table = *fBitmap;
195    }
196    return true;
197}
198
199///////////////////////////////////////////////////////////////////////////////
200
201#ifdef SK_CPU_BENDIAN
202#else
203    #define SK_A32_INDEX    (3 - (SK_A32_SHIFT >> 3))
204    #define SK_R32_INDEX    (3 - (SK_R32_SHIFT >> 3))
205    #define SK_G32_INDEX    (3 - (SK_G32_SHIFT >> 3))
206    #define SK_B32_INDEX    (3 - (SK_B32_SHIFT >> 3))
207#endif
208
209///////////////////////////////////////////////////////////////////////////////
210
211SkColorFilter* SkTableColorFilter::Create(const uint8_t table[256]) {
212    return SkNEW_ARGS(SkTable_ColorFilter, (table, table, table, table));
213}
214
215SkColorFilter* SkTableColorFilter::CreateARGB(const uint8_t tableA[256],
216                                              const uint8_t tableR[256],
217                                              const uint8_t tableG[256],
218                                              const uint8_t tableB[256]) {
219    return SkNEW_ARGS(SkTable_ColorFilter, (tableA, tableR, tableG, tableB));
220}
221