1
2 /*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10 #include "SkCoreBlitters.h"
11 #include "SkColorPriv.h"
12 #include "SkShader.h"
13 #include "SkXfermode.h"
14
SkA8_Blitter(const SkBitmap & device,const SkPaint & paint)15 SkA8_Blitter::SkA8_Blitter(const SkBitmap& device, const SkPaint& paint)
16 : INHERITED(device) {
17 fSrcA = paint.getAlpha();
18 }
19
justAnOpaqueColor(uint32_t * value)20 const SkBitmap* SkA8_Blitter::justAnOpaqueColor(uint32_t* value) {
21 if (255 == fSrcA) {
22 *value = 255;
23 return &fDevice;
24 }
25 return NULL;
26 }
27
blitH(int x,int y,int width)28 void SkA8_Blitter::blitH(int x, int y, int width) {
29 SkASSERT(x >= 0 && y >= 0 &&
30 (unsigned)(x + width) <= (unsigned)fDevice.width());
31
32 if (fSrcA == 0) {
33 return;
34 }
35
36 uint8_t* device = fDevice.getAddr8(x, y);
37
38 if (fSrcA == 255) {
39 memset(device, 0xFF, width);
40 } else {
41 unsigned scale = 256 - SkAlpha255To256(fSrcA);
42 unsigned srcA = fSrcA;
43
44 for (int i = 0; i < width; i++) {
45 device[i] = SkToU8(srcA + SkAlphaMul(device[i], scale));
46 }
47 }
48 }
49
blitAntiH(int x,int y,const SkAlpha antialias[],const int16_t runs[])50 void SkA8_Blitter::blitAntiH(int x, int y, const SkAlpha antialias[],
51 const int16_t runs[]) {
52 if (fSrcA == 0) {
53 return;
54 }
55
56 uint8_t* device = fDevice.getAddr8(x, y);
57 unsigned srcA = fSrcA;
58
59 for (;;) {
60 int count = runs[0];
61 SkASSERT(count >= 0);
62 if (count == 0) {
63 return;
64 }
65 unsigned aa = antialias[0];
66
67 if (aa == 255 && srcA == 255) {
68 memset(device, 0xFF, count);
69 } else {
70 unsigned sa = SkAlphaMul(srcA, SkAlpha255To256(aa));
71 unsigned scale = 256 - sa;
72
73 for (int i = 0; i < count; i++) {
74 device[i] = SkToU8(sa + SkAlphaMul(device[i], scale));
75 }
76 }
77 runs += count;
78 antialias += count;
79 device += count;
80 }
81 }
82
83 /////////////////////////////////////////////////////////////////////////////////////
84
85 #define solid_8_pixels(mask, dst) \
86 do { \
87 if (mask & 0x80) dst[0] = 0xFF; \
88 if (mask & 0x40) dst[1] = 0xFF; \
89 if (mask & 0x20) dst[2] = 0xFF; \
90 if (mask & 0x10) dst[3] = 0xFF; \
91 if (mask & 0x08) dst[4] = 0xFF; \
92 if (mask & 0x04) dst[5] = 0xFF; \
93 if (mask & 0x02) dst[6] = 0xFF; \
94 if (mask & 0x01) dst[7] = 0xFF; \
95 } while (0)
96
97 #define SK_BLITBWMASK_NAME SkA8_BlitBW
98 #define SK_BLITBWMASK_ARGS
99 #define SK_BLITBWMASK_BLIT8(mask, dst) solid_8_pixels(mask, dst)
100 #define SK_BLITBWMASK_GETADDR getAddr8
101 #define SK_BLITBWMASK_DEVTYPE uint8_t
102 #include "SkBlitBWMaskTemplate.h"
103
blend_8_pixels(U8CPU bw,uint8_t dst[],U8CPU sa,unsigned dst_scale)104 static inline void blend_8_pixels(U8CPU bw, uint8_t dst[], U8CPU sa,
105 unsigned dst_scale) {
106 if (bw & 0x80) dst[0] = SkToU8(sa + SkAlphaMul(dst[0], dst_scale));
107 if (bw & 0x40) dst[1] = SkToU8(sa + SkAlphaMul(dst[1], dst_scale));
108 if (bw & 0x20) dst[2] = SkToU8(sa + SkAlphaMul(dst[2], dst_scale));
109 if (bw & 0x10) dst[3] = SkToU8(sa + SkAlphaMul(dst[3], dst_scale));
110 if (bw & 0x08) dst[4] = SkToU8(sa + SkAlphaMul(dst[4], dst_scale));
111 if (bw & 0x04) dst[5] = SkToU8(sa + SkAlphaMul(dst[5], dst_scale));
112 if (bw & 0x02) dst[6] = SkToU8(sa + SkAlphaMul(dst[6], dst_scale));
113 if (bw & 0x01) dst[7] = SkToU8(sa + SkAlphaMul(dst[7], dst_scale));
114 }
115
116 #define SK_BLITBWMASK_NAME SkA8_BlendBW
117 #define SK_BLITBWMASK_ARGS , U8CPU sa, unsigned dst_scale
118 #define SK_BLITBWMASK_BLIT8(mask, dst) blend_8_pixels(mask, dst, sa, dst_scale)
119 #define SK_BLITBWMASK_GETADDR getAddr8
120 #define SK_BLITBWMASK_DEVTYPE uint8_t
121 #include "SkBlitBWMaskTemplate.h"
122
blitMask(const SkMask & mask,const SkIRect & clip)123 void SkA8_Blitter::blitMask(const SkMask& mask, const SkIRect& clip) {
124 if (fSrcA == 0) {
125 return;
126 }
127
128 if (mask.fFormat == SkMask::kBW_Format) {
129 if (fSrcA == 0xFF) {
130 SkA8_BlitBW(fDevice, mask, clip);
131 } else {
132 SkA8_BlendBW(fDevice, mask, clip, fSrcA,
133 SkAlpha255To256(255 - fSrcA));
134 }
135 return;
136 }
137
138 int x = clip.fLeft;
139 int y = clip.fTop;
140 int width = clip.width();
141 int height = clip.height();
142 uint8_t* device = fDevice.getAddr8(x, y);
143 const uint8_t* alpha = mask.getAddr8(x, y);
144 unsigned srcA = fSrcA;
145
146 while (--height >= 0) {
147 for (int i = width - 1; i >= 0; --i) {
148 unsigned sa;
149 // scale our src by the alpha value
150 {
151 int aa = alpha[i];
152 if (aa == 0) {
153 continue;
154 }
155 if (aa == 255) {
156 if (srcA == 255) {
157 device[i] = 0xFF;
158 continue;
159 }
160 sa = srcA;
161 } else {
162 sa = SkAlphaMul(srcA, SkAlpha255To256(aa));
163 }
164 }
165
166 int scale = 256 - SkAlpha255To256(sa);
167 device[i] = SkToU8(sa + SkAlphaMul(device[i], scale));
168 }
169 device += fDevice.rowBytes();
170 alpha += mask.fRowBytes;
171 }
172 }
173
174 ///////////////////////////////////////////////////////////////////////////////
175
blitV(int x,int y,int height,SkAlpha alpha)176 void SkA8_Blitter::blitV(int x, int y, int height, SkAlpha alpha) {
177 if (fSrcA == 0) {
178 return;
179 }
180
181 unsigned sa = SkAlphaMul(fSrcA, SkAlpha255To256(alpha));
182 uint8_t* device = fDevice.getAddr8(x, y);
183 int rowBytes = fDevice.rowBytes();
184
185 if (sa == 0xFF) {
186 for (int i = 0; i < height; i++) {
187 *device = SkToU8(sa);
188 device += rowBytes;
189 }
190 } else {
191 unsigned scale = 256 - SkAlpha255To256(sa);
192
193 for (int i = 0; i < height; i++) {
194 *device = SkToU8(sa + SkAlphaMul(*device, scale));
195 device += rowBytes;
196 }
197 }
198 }
199
blitRect(int x,int y,int width,int height)200 void SkA8_Blitter::blitRect(int x, int y, int width, int height) {
201 SkASSERT(x >= 0 && y >= 0 &&
202 (unsigned)(x + width) <= (unsigned)fDevice.width() &&
203 (unsigned)(y + height) <= (unsigned)fDevice.height());
204
205 if (fSrcA == 0) {
206 return;
207 }
208
209 uint8_t* device = fDevice.getAddr8(x, y);
210 unsigned srcA = fSrcA;
211
212 if (srcA == 255) {
213 while (--height >= 0) {
214 memset(device, 0xFF, width);
215 device += fDevice.rowBytes();
216 }
217 } else {
218 unsigned scale = 256 - SkAlpha255To256(srcA);
219
220 while (--height >= 0) {
221 for (int i = 0; i < width; i++) {
222 device[i] = SkToU8(srcA + SkAlphaMul(device[i], scale));
223 }
224 device += fDevice.rowBytes();
225 }
226 }
227 }
228
229 ///////////////////////////////////////////////////////////////////////
230
SkA8_Shader_Blitter(const SkBitmap & device,const SkPaint & paint)231 SkA8_Shader_Blitter::SkA8_Shader_Blitter(const SkBitmap& device, const SkPaint& paint)
232 : INHERITED(device, paint) {
233 if ((fXfermode = paint.getXfermode()) != NULL) {
234 fXfermode->ref();
235 SkASSERT(fShader);
236 }
237
238 int width = device.width();
239 fBuffer = (SkPMColor*)sk_malloc_throw(sizeof(SkPMColor) * (width + (SkAlign4(width) >> 2)));
240 fAAExpand = (uint8_t*)(fBuffer + width);
241 }
242
~SkA8_Shader_Blitter()243 SkA8_Shader_Blitter::~SkA8_Shader_Blitter() {
244 if (fXfermode) SkSafeUnref(fXfermode);
245 sk_free(fBuffer);
246 }
247
blitH(int x,int y,int width)248 void SkA8_Shader_Blitter::blitH(int x, int y, int width) {
249 SkASSERT(x >= 0 && y >= 0 &&
250 (unsigned)(x + width) <= (unsigned)fDevice.width());
251
252 uint8_t* device = fDevice.getAddr8(x, y);
253
254 if ((fShader->getFlags() & SkShader::kOpaqueAlpha_Flag) && !fXfermode) {
255 memset(device, 0xFF, width);
256 } else {
257 SkPMColor* span = fBuffer;
258
259 fShader->shadeSpan(x, y, span, width);
260 if (fXfermode) {
261 fXfermode->xferA8(device, span, width, NULL);
262 } else {
263 for (int i = width - 1; i >= 0; --i) {
264 unsigned srcA = SkGetPackedA32(span[i]);
265 unsigned scale = 256 - SkAlpha255To256(srcA);
266
267 device[i] = SkToU8(srcA + SkAlphaMul(device[i], scale));
268 }
269 }
270 }
271 }
272
aa_blend8(SkPMColor src,U8CPU da,int aa)273 static inline uint8_t aa_blend8(SkPMColor src, U8CPU da, int aa) {
274 SkASSERT((unsigned)aa <= 255);
275
276 int src_scale = SkAlpha255To256(aa);
277 int sa = SkGetPackedA32(src);
278 int dst_scale = 256 - SkAlphaMul(sa, src_scale);
279
280 return SkToU8((sa * src_scale + da * dst_scale) >> 8);
281 }
282
blitAntiH(int x,int y,const SkAlpha antialias[],const int16_t runs[])283 void SkA8_Shader_Blitter::blitAntiH(int x, int y, const SkAlpha antialias[],
284 const int16_t runs[]) {
285 SkShader* shader = fShader;
286 SkXfermode* mode = fXfermode;
287 uint8_t* aaExpand = fAAExpand;
288 SkPMColor* span = fBuffer;
289 uint8_t* device = fDevice.getAddr8(x, y);
290 int opaque = fShader->getFlags() & SkShader::kOpaqueAlpha_Flag;
291
292 for (;;) {
293 int count = *runs;
294 if (count == 0) {
295 break;
296 }
297 int aa = *antialias;
298 if (aa) {
299 if (opaque && aa == 255 && mode == NULL) {
300 memset(device, 0xFF, count);
301 } else {
302 shader->shadeSpan(x, y, span, count);
303 if (mode) {
304 memset(aaExpand, aa, count);
305 mode->xferA8(device, span, count, aaExpand);
306 } else {
307 for (int i = count - 1; i >= 0; --i) {
308 device[i] = aa_blend8(span[i], device[i], aa);
309 }
310 }
311 }
312 }
313 device += count;
314 runs += count;
315 antialias += count;
316 x += count;
317 }
318 }
319
blitMask(const SkMask & mask,const SkIRect & clip)320 void SkA8_Shader_Blitter::blitMask(const SkMask& mask, const SkIRect& clip) {
321 if (mask.fFormat == SkMask::kBW_Format) {
322 this->INHERITED::blitMask(mask, clip);
323 return;
324 }
325
326 int x = clip.fLeft;
327 int y = clip.fTop;
328 int width = clip.width();
329 int height = clip.height();
330 uint8_t* device = fDevice.getAddr8(x, y);
331 const uint8_t* alpha = mask.getAddr8(x, y);
332
333 SkPMColor* span = fBuffer;
334
335 while (--height >= 0) {
336 fShader->shadeSpan(x, y, span, width);
337 if (fXfermode) {
338 fXfermode->xferA8(device, span, width, alpha);
339 }
340
341 y += 1;
342 device += fDevice.rowBytes();
343 alpha += mask.fRowBytes;
344 }
345 }
346
347