1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2012 Sam Lantinga
4
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19 Sam Lantinga
20 slouken@libsdl.org
21 */
22 #include "SDL_config.h"
23
24 #include "SDL_video.h"
25 #include "SDL_blit.h"
26
27 /* Functions to blit from bitmaps to other surfaces */
28
BlitBto1(SDL_BlitInfo * info)29 static void BlitBto1(SDL_BlitInfo *info)
30 {
31 int c;
32 int width, height;
33 Uint8 *src, *map, *dst;
34 int srcskip, dstskip;
35
36 /* Set up some basic variables */
37 width = info->d_width;
38 height = info->d_height;
39 src = info->s_pixels;
40 srcskip = info->s_skip;
41 dst = info->d_pixels;
42 dstskip = info->d_skip;
43 map = info->table;
44 srcskip += width-(width+7)/8;
45
46 if ( map ) {
47 while ( height-- ) {
48 Uint8 byte = 0, bit;
49 for ( c=0; c<width; ++c ) {
50 if ( (c&7) == 0 ) {
51 byte = *src++;
52 }
53 bit = (byte&0x80)>>7;
54 if ( 1 ) {
55 *dst = map[bit];
56 }
57 dst++;
58 byte <<= 1;
59 }
60 src += srcskip;
61 dst += dstskip;
62 }
63 } else {
64 while ( height-- ) {
65 Uint8 byte = 0, bit;
66 for ( c=0; c<width; ++c ) {
67 if ( (c&7) == 0 ) {
68 byte = *src++;
69 }
70 bit = (byte&0x80)>>7;
71 if ( 1 ) {
72 *dst = bit;
73 }
74 dst++;
75 byte <<= 1;
76 }
77 src += srcskip;
78 dst += dstskip;
79 }
80 }
81 }
BlitBto2(SDL_BlitInfo * info)82 static void BlitBto2(SDL_BlitInfo *info)
83 {
84 int c;
85 int width, height;
86 Uint8 *src;
87 Uint16 *map, *dst;
88 int srcskip, dstskip;
89
90 /* Set up some basic variables */
91 width = info->d_width;
92 height = info->d_height;
93 src = info->s_pixels;
94 srcskip = info->s_skip;
95 dst = (Uint16 *)info->d_pixels;
96 dstskip = info->d_skip/2;
97 map = (Uint16 *)info->table;
98 srcskip += width-(width+7)/8;
99
100 while ( height-- ) {
101 Uint8 byte = 0, bit;
102 for ( c=0; c<width; ++c ) {
103 if ( (c&7) == 0 ) {
104 byte = *src++;
105 }
106 bit = (byte&0x80)>>7;
107 if ( 1 ) {
108 *dst = map[bit];
109 }
110 byte <<= 1;
111 dst++;
112 }
113 src += srcskip;
114 dst += dstskip;
115 }
116 }
BlitBto3(SDL_BlitInfo * info)117 static void BlitBto3(SDL_BlitInfo *info)
118 {
119 int c, o;
120 int width, height;
121 Uint8 *src, *map, *dst;
122 int srcskip, dstskip;
123
124 /* Set up some basic variables */
125 width = info->d_width;
126 height = info->d_height;
127 src = info->s_pixels;
128 srcskip = info->s_skip;
129 dst = info->d_pixels;
130 dstskip = info->d_skip;
131 map = info->table;
132 srcskip += width-(width+7)/8;
133
134 while ( height-- ) {
135 Uint8 byte = 0, bit;
136 for ( c=0; c<width; ++c ) {
137 if ( (c&7) == 0 ) {
138 byte = *src++;
139 }
140 bit = (byte&0x80)>>7;
141 if ( 1 ) {
142 o = bit * 4;
143 dst[0] = map[o++];
144 dst[1] = map[o++];
145 dst[2] = map[o++];
146 }
147 byte <<= 1;
148 dst += 3;
149 }
150 src += srcskip;
151 dst += dstskip;
152 }
153 }
BlitBto4(SDL_BlitInfo * info)154 static void BlitBto4(SDL_BlitInfo *info)
155 {
156 int width, height;
157 Uint8 *src;
158 Uint32 *map, *dst;
159 int srcskip, dstskip;
160 int c;
161
162 /* Set up some basic variables */
163 width = info->d_width;
164 height = info->d_height;
165 src = info->s_pixels;
166 srcskip = info->s_skip;
167 dst = (Uint32 *)info->d_pixels;
168 dstskip = info->d_skip/4;
169 map = (Uint32 *)info->table;
170 srcskip += width-(width+7)/8;
171
172 while ( height-- ) {
173 Uint8 byte = 0, bit;
174 for ( c=0; c<width; ++c ) {
175 if ( (c&7) == 0 ) {
176 byte = *src++;
177 }
178 bit = (byte&0x80)>>7;
179 if ( 1 ) {
180 *dst = map[bit];
181 }
182 byte <<= 1;
183 dst++;
184 }
185 src += srcskip;
186 dst += dstskip;
187 }
188 }
189
BlitBto1Key(SDL_BlitInfo * info)190 static void BlitBto1Key(SDL_BlitInfo *info)
191 {
192 int width = info->d_width;
193 int height = info->d_height;
194 Uint8 *src = info->s_pixels;
195 Uint8 *dst = info->d_pixels;
196 int srcskip = info->s_skip;
197 int dstskip = info->d_skip;
198 Uint32 ckey = info->src->colorkey;
199 Uint8 *palmap = info->table;
200 int c;
201
202 /* Set up some basic variables */
203 srcskip += width-(width+7)/8;
204
205 if ( palmap ) {
206 while ( height-- ) {
207 Uint8 byte = 0, bit;
208 for ( c=0; c<width; ++c ) {
209 if ( (c&7) == 0 ) {
210 byte = *src++;
211 }
212 bit = (byte&0x80)>>7;
213 if ( bit != ckey ) {
214 *dst = palmap[bit];
215 }
216 dst++;
217 byte <<= 1;
218 }
219 src += srcskip;
220 dst += dstskip;
221 }
222 } else {
223 while ( height-- ) {
224 Uint8 byte = 0, bit;
225 for ( c=0; c<width; ++c ) {
226 if ( (c&7) == 0 ) {
227 byte = *src++;
228 }
229 bit = (byte&0x80)>>7;
230 if ( bit != ckey ) {
231 *dst = bit;
232 }
233 dst++;
234 byte <<= 1;
235 }
236 src += srcskip;
237 dst += dstskip;
238 }
239 }
240 }
241
BlitBto2Key(SDL_BlitInfo * info)242 static void BlitBto2Key(SDL_BlitInfo *info)
243 {
244 int width = info->d_width;
245 int height = info->d_height;
246 Uint8 *src = info->s_pixels;
247 Uint16 *dstp = (Uint16 *)info->d_pixels;
248 int srcskip = info->s_skip;
249 int dstskip = info->d_skip;
250 Uint32 ckey = info->src->colorkey;
251 Uint8 *palmap = info->table;
252 int c;
253
254 /* Set up some basic variables */
255 srcskip += width-(width+7)/8;
256 dstskip /= 2;
257
258 while ( height-- ) {
259 Uint8 byte = 0, bit;
260 for ( c=0; c<width; ++c ) {
261 if ( (c&7) == 0 ) {
262 byte = *src++;
263 }
264 bit = (byte&0x80)>>7;
265 if ( bit != ckey ) {
266 *dstp=((Uint16 *)palmap)[bit];
267 }
268 byte <<= 1;
269 dstp++;
270 }
271 src += srcskip;
272 dstp += dstskip;
273 }
274 }
275
BlitBto3Key(SDL_BlitInfo * info)276 static void BlitBto3Key(SDL_BlitInfo *info)
277 {
278 int width = info->d_width;
279 int height = info->d_height;
280 Uint8 *src = info->s_pixels;
281 Uint8 *dst = info->d_pixels;
282 int srcskip = info->s_skip;
283 int dstskip = info->d_skip;
284 Uint32 ckey = info->src->colorkey;
285 Uint8 *palmap = info->table;
286 int c;
287
288 /* Set up some basic variables */
289 srcskip += width-(width+7)/8;
290
291 while ( height-- ) {
292 Uint8 byte = 0, bit;
293 for ( c=0; c<width; ++c ) {
294 if ( (c&7) == 0 ) {
295 byte = *src++;
296 }
297 bit = (byte&0x80)>>7;
298 if ( bit != ckey ) {
299 SDL_memcpy(dst, &palmap[bit*4], 3);
300 }
301 byte <<= 1;
302 dst += 3;
303 }
304 src += srcskip;
305 dst += dstskip;
306 }
307 }
308
BlitBto4Key(SDL_BlitInfo * info)309 static void BlitBto4Key(SDL_BlitInfo *info)
310 {
311 int width = info->d_width;
312 int height = info->d_height;
313 Uint8 *src = info->s_pixels;
314 Uint32 *dstp = (Uint32 *)info->d_pixels;
315 int srcskip = info->s_skip;
316 int dstskip = info->d_skip;
317 Uint32 ckey = info->src->colorkey;
318 Uint8 *palmap = info->table;
319 int c;
320
321 /* Set up some basic variables */
322 srcskip += width-(width+7)/8;
323 dstskip /= 4;
324
325 while ( height-- ) {
326 Uint8 byte = 0, bit;
327 for ( c=0; c<width; ++c ) {
328 if ( (c&7) == 0 ) {
329 byte = *src++;
330 }
331 bit = (byte&0x80)>>7;
332 if ( bit != ckey ) {
333 *dstp=((Uint32 *)palmap)[bit];
334 }
335 byte <<= 1;
336 dstp++;
337 }
338 src += srcskip;
339 dstp += dstskip;
340 }
341 }
342
BlitBtoNAlpha(SDL_BlitInfo * info)343 static void BlitBtoNAlpha(SDL_BlitInfo *info)
344 {
345 int width = info->d_width;
346 int height = info->d_height;
347 Uint8 *src = info->s_pixels;
348 Uint8 *dst = info->d_pixels;
349 int srcskip = info->s_skip;
350 int dstskip = info->d_skip;
351 const SDL_Color *srcpal = info->src->palette->colors;
352 SDL_PixelFormat *dstfmt = info->dst;
353 int dstbpp;
354 int c;
355 const int A = info->src->alpha;
356
357 /* Set up some basic variables */
358 dstbpp = dstfmt->BytesPerPixel;
359 srcskip += width-(width+7)/8;
360
361 while ( height-- ) {
362 Uint8 byte = 0, bit;
363 for ( c=0; c<width; ++c ) {
364 if ( (c&7) == 0 ) {
365 byte = *src++;
366 }
367 bit = (byte&0x80)>>7;
368 if ( 1 ) {
369 Uint32 pixel;
370 unsigned sR, sG, sB;
371 unsigned dR, dG, dB;
372 sR = srcpal[bit].r;
373 sG = srcpal[bit].g;
374 sB = srcpal[bit].b;
375 DISEMBLE_RGB(dst, dstbpp, dstfmt,
376 pixel, dR, dG, dB);
377 ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
378 ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
379 }
380 byte <<= 1;
381 dst += dstbpp;
382 }
383 src += srcskip;
384 dst += dstskip;
385 }
386 }
387
BlitBtoNAlphaKey(SDL_BlitInfo * info)388 static void BlitBtoNAlphaKey(SDL_BlitInfo *info)
389 {
390 int width = info->d_width;
391 int height = info->d_height;
392 Uint8 *src = info->s_pixels;
393 Uint8 *dst = info->d_pixels;
394 int srcskip = info->s_skip;
395 int dstskip = info->d_skip;
396 SDL_PixelFormat *srcfmt = info->src;
397 SDL_PixelFormat *dstfmt = info->dst;
398 const SDL_Color *srcpal = srcfmt->palette->colors;
399 int dstbpp;
400 int c;
401 const int A = srcfmt->alpha;
402 Uint32 ckey = srcfmt->colorkey;
403
404 /* Set up some basic variables */
405 dstbpp = dstfmt->BytesPerPixel;
406 srcskip += width-(width+7)/8;
407
408 while ( height-- ) {
409 Uint8 byte = 0, bit;
410 for ( c=0; c<width; ++c ) {
411 if ( (c&7) == 0 ) {
412 byte = *src++;
413 }
414 bit = (byte&0x80)>>7;
415 if ( bit != ckey ) {
416 int sR, sG, sB;
417 int dR, dG, dB;
418 Uint32 pixel;
419 sR = srcpal[bit].r;
420 sG = srcpal[bit].g;
421 sB = srcpal[bit].b;
422 DISEMBLE_RGB(dst, dstbpp, dstfmt,
423 pixel, dR, dG, dB);
424 ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
425 ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
426 }
427 byte <<= 1;
428 dst += dstbpp;
429 }
430 src += srcskip;
431 dst += dstskip;
432 }
433 }
434
435 static SDL_loblit bitmap_blit[] = {
436 NULL, BlitBto1, BlitBto2, BlitBto3, BlitBto4
437 };
438
439 static SDL_loblit colorkey_blit[] = {
440 NULL, BlitBto1Key, BlitBto2Key, BlitBto3Key, BlitBto4Key
441 };
442
SDL_CalculateBlit0(SDL_Surface * surface,int blit_index)443 SDL_loblit SDL_CalculateBlit0(SDL_Surface *surface, int blit_index)
444 {
445 int which;
446
447 if ( surface->format->BitsPerPixel != 1 ) {
448 /* We don't support sub 8-bit packed pixel modes */
449 return NULL;
450 }
451 if ( surface->map->dst->format->BitsPerPixel < 8 ) {
452 which = 0;
453 } else {
454 which = surface->map->dst->format->BytesPerPixel;
455 }
456 switch(blit_index) {
457 case 0: /* copy */
458 return bitmap_blit[which];
459
460 case 1: /* colorkey */
461 return colorkey_blit[which];
462
463 case 2: /* alpha */
464 return which >= 2 ? BlitBtoNAlpha : NULL;
465
466 case 4: /* alpha + colorkey */
467 return which >= 2 ? BlitBtoNAlphaKey : NULL;
468 }
469 return NULL;
470 }
471
472