src/video/SDL_blit_0.c
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FUNCTIONS
This source file includes following functions.
- BlitBto1
- BlitBto2
- BlitBto3
- BlitBto4
- BlitBto1Key
- BlitBto2Key
- BlitBto3Key
- BlitBto4Key
- BlitBtoNAlpha
- BlitBtoNAlphaKey
- SDL_CalculateBlit0
1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga
4
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public
7 License as published by the Free Software Foundation; either
8 version 2 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 Library General Public License for more details.
14
15 You should have received a copy of the GNU Library General Public
16 License along with this library; if not, write to the Free
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
19 Sam Lantinga
20 slouken@devolution.com
21 */
22
23 #ifdef SAVE_RCSID
24 static char rcsid =
25 "@(#) $Id: SDL_blit_0.c,v 1.2.2.4 2001/02/10 07:20:05 hercules Exp $";
26 #endif
27
28 #include <stdio.h>
29 #include <string.h>
30
31 #include "SDL_types.h"
32 #include "SDL_video.h"
33 #include "SDL_blit.h"
34
35 /* Functions to blit from bitmaps to other surfaces */
36
37 static void BlitBto1(SDL_BlitInfo *info)
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38 {
39 int c;
40 int width, height;
41 Uint8 *src, *map, *dst;
42 int srcskip, dstskip;
43
44 /* Set up some basic variables */
45 width = info->d_width;
46 height = info->d_height;
47 src = info->s_pixels;
48 srcskip = info->s_skip;
49 dst = info->d_pixels;
50 dstskip = info->d_skip;
51 map = info->table;
52 srcskip += width-(width+7)/8;
53
54 if ( map ) {
55 while ( height-- ) {
56 Uint8 byte = 0, bit;
57 for ( c=0; c<width; ++c ) {
58 if ( (c%8) == 0 ) {
59 byte = *src++;
60 }
61 bit = (byte&0x80)>>7;
62 if ( 1 ) {
63 *dst = map[bit];
64 }
65 dst++;
66 byte <<= 1;
67 }
68 src += srcskip;
69 dst += dstskip;
70 }
71 } else {
72 while ( height-- ) {
73 Uint8 byte = 0, bit;
74 for ( c=0; c<width; ++c ) {
75 if ( (c%8) == 0 ) {
76 byte = *src++;
77 }
78 bit = (byte&0x80)>>7;
79 if ( 1 ) {
80 *dst = bit;
81 }
82 dst++;
83 byte <<= 1;
84 }
85 src += srcskip;
86 dst += dstskip;
87 }
88 }
89 }
90 static void BlitBto2(SDL_BlitInfo *info)
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91 {
92 int c;
93 int width, height;
94 Uint8 *src;
95 Uint16 *map, *dst;
96 int srcskip, dstskip;
97
98 /* Set up some basic variables */
99 width = info->d_width;
100 height = info->d_height;
101 src = info->s_pixels;
102 srcskip = info->s_skip;
103 dst = (Uint16 *)info->d_pixels;
104 dstskip = info->d_skip/2;
105 map = (Uint16 *)info->table;
106 srcskip += width-(width+7)/8;
107
108 while ( height-- ) {
109 Uint8 byte = 0, bit;
110 for ( c=0; c<width; ++c ) {
111 if ( (c%8) == 0 ) {
112 byte = *src++;
113 }
114 bit = (byte&0x80)>>7;
115 if ( 1 ) {
116 *dst = map[bit];
117 }
118 byte <<= 1;
119 dst++;
120 }
121 src += srcskip;
122 dst += dstskip;
123 }
124 }
125 static void BlitBto3(SDL_BlitInfo *info)
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126 {
127 int c, o;
128 int width, height;
129 Uint8 *src, *map, *dst;
130 int srcskip, dstskip;
131
132 /* Set up some basic variables */
133 width = info->d_width;
134 height = info->d_height;
135 src = info->s_pixels;
136 srcskip = info->s_skip;
137 dst = info->d_pixels;
138 dstskip = info->d_skip;
139 map = info->table;
140 srcskip += width-(width+7)/8;
141
142 while ( height-- ) {
143 Uint8 byte = 0, bit;
144 for ( c=0; c<width; ++c ) {
145 if ( (c%8) == 0 ) {
146 byte = *src++;
147 }
148 bit = (byte&0x80)>>7;
149 if ( 1 ) {
150 o = bit * 4;
151 dst[0] = map[o++];
152 dst[1] = map[o++];
153 dst[2] = map[o++];
154 }
155 byte <<= 1;
156 dst += 3;
157 }
158 src += srcskip;
159 dst += dstskip;
160 }
161 }
162 static void BlitBto4(SDL_BlitInfo *info)
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163 {
164 int width, height;
165 Uint8 *src;
166 Uint32 *map, *dst;
167 int srcskip, dstskip;
168 int c;
169
170 /* Set up some basic variables */
171 width = info->d_width;
172 height = info->d_height;
173 src = info->s_pixels;
174 srcskip = info->s_skip;
175 dst = (Uint32 *)info->d_pixels;
176 dstskip = info->d_skip/4;
177 map = (Uint32 *)info->table;
178 srcskip += width-(width+7)/8;
179
180 while ( height-- ) {
181 Uint8 byte = 0, bit;
182 for ( c=0; c<width; ++c ) {
183 if ( (c%8) == 0 ) {
184 byte = *src++;
185 }
186 bit = (byte&0x80)>>7;
187 if ( 1 ) {
188 *dst = map[bit];
189 }
190 byte <<= 1;
191 dst++;
192 }
193 src += srcskip;
194 dst += dstskip;
195 }
196 }
197
198 static void BlitBto1Key(SDL_BlitInfo *info)
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199 {
200 int width = info->d_width;
201 int height = info->d_height;
202 Uint8 *src = info->s_pixels;
203 Uint8 *dst = info->d_pixels;
204 int srcskip = info->s_skip;
205 int dstskip = info->d_skip;
206 Uint32 ckey = info->src->colorkey;
207 Uint8 *palmap = info->table;
208 int c;
209
210 /* Set up some basic variables */
211 srcskip += width-(width+7)/8;
212
213 if ( palmap ) {
214 while ( height-- ) {
215 Uint8 byte = 0, bit;
216 for ( c=0; c<width; ++c ) {
217 if ( (c%8) == 0 ) {
218 byte = *src++;
219 }
220 bit = (byte&0x80)>>7;
221 if ( bit != ckey ) {
222 *dst = palmap[bit];
223 }
224 dst++;
225 byte <<= 1;
226 }
227 src += srcskip;
228 dst += dstskip;
229 }
230 } else {
231 while ( height-- ) {
232 Uint8 byte = 0, bit;
233 for ( c=0; c<width; ++c ) {
234 if ( (c%8) == 0 ) {
235 byte = *src++;
236 }
237 bit = (byte&0x80)>>7;
238 if ( bit != ckey ) {
239 *dst = bit;
240 }
241 dst++;
242 byte <<= 1;
243 }
244 src += srcskip;
245 dst += dstskip;
246 }
247 }
248 }
249
250 static void BlitBto2Key(SDL_BlitInfo *info)
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251 {
252 int width = info->d_width;
253 int height = info->d_height;
254 Uint8 *src = info->s_pixels;
255 Uint16 *dstp = (Uint16 *)info->d_pixels;
256 int srcskip = info->s_skip;
257 int dstskip = info->d_skip;
258 Uint32 ckey = info->src->colorkey;
259 Uint8 *palmap = info->table;
260 int c;
261
262 /* Set up some basic variables */
263 srcskip += width-(width+7)/8;
264 dstskip /= 2;
265
266 while ( height-- ) {
267 Uint8 byte = 0, bit;
268 for ( c=0; c<width; ++c ) {
269 if ( (c%8) == 0 ) {
270 byte = *src++;
271 }
272 bit = (byte&0x80)>>7;
273 if ( bit != ckey ) {
274 *dstp=((Uint16 *)palmap)[bit];
275 }
276 byte <<= 1;
277 dstp++;
278 }
279 src += srcskip;
280 dstp += dstskip;
281 }
282 }
283
284 static void BlitBto3Key(SDL_BlitInfo *info)
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285 {
286 int width = info->d_width;
287 int height = info->d_height;
288 Uint8 *src = info->s_pixels;
289 Uint8 *dst = info->d_pixels;
290 int srcskip = info->s_skip;
291 int dstskip = info->d_skip;
292 Uint32 ckey = info->src->colorkey;
293 Uint8 *palmap = info->table;
294 int c;
295
296 /* Set up some basic variables */
297 srcskip += width-(width+7)/8;
298
299 while ( height-- ) {
300 Uint8 byte = 0, bit;
301 for ( c=0; c<width; ++c ) {
302 if ( (c%8) == 0 ) {
303 byte = *src++;
304 }
305 bit = (byte&0x80)>>7;
306 if ( bit != ckey ) {
307 memcpy(dst, &palmap[bit*4], 3);
308 }
309 byte <<= 1;
310 dst += 3;
311 }
312 src += srcskip;
313 dst += dstskip;
314 }
315 }
316
317 static void BlitBto4Key(SDL_BlitInfo *info)
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318 {
319 int width = info->d_width;
320 int height = info->d_height;
321 Uint8 *src = info->s_pixels;
322 Uint32 *dstp = (Uint32 *)info->d_pixels;
323 int srcskip = info->s_skip;
324 int dstskip = info->d_skip;
325 Uint32 ckey = info->src->colorkey;
326 Uint8 *palmap = info->table;
327 int c;
328
329 /* Set up some basic variables */
330 srcskip += width-(width+7)/8;
331 dstskip /= 4;
332
333 while ( height-- ) {
334 Uint8 byte = 0, bit;
335 for ( c=0; c<width; ++c ) {
336 if ( (c%8) == 0 ) {
337 byte = *src++;
338 }
339 bit = (byte&0x80)>>7;
340 if ( bit != ckey ) {
341 *dstp=((Uint32 *)palmap)[bit];
342 }
343 byte <<= 1;
344 dstp++;
345 }
346 src += srcskip;
347 dstp += dstskip;
348 }
349 }
350
351 static void BlitBtoNAlpha(SDL_BlitInfo *info)
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352 {
353 int width = info->d_width;
354 int height = info->d_height;
355 Uint8 *src = info->s_pixels;
356 Uint8 *dst = info->d_pixels;
357 int srcskip = info->s_skip;
358 int dstskip = info->d_skip;
359 const SDL_Color *srcpal = info->src->palette->colors;
360 SDL_PixelFormat *dstfmt = info->dst;
361 int dstbpp;
362 int c;
363 const int A = info->src->alpha;
364
365 /* Set up some basic variables */
366 dstbpp = dstfmt->BytesPerPixel;
367 srcskip += width-(width+7)/8;
368
369 while ( height-- ) {
370 Uint8 byte = 0, bit;
371 for ( c=0; c<width; ++c ) {
372 if ( (c%8) == 0 ) {
373 byte = *src++;
374 }
375 bit = (byte&0x80)>>7;
376 if ( 1 ) {
377 Uint32 pixel;
378 unsigned sR, sG, sB;
379 unsigned dR, dG, dB;
380 sR = srcpal[bit].r;
381 sG = srcpal[bit].g;
382 sB = srcpal[bit].b;
383 DISEMBLE_RGB(dst, dstbpp, dstfmt,
384 pixel, dR, dG, dB);
385 ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
386 ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
387 }
388 byte <<= 1;
389 dst += dstbpp;
390 }
391 src += srcskip;
392 dst += dstskip;
393 }
394 }
395
396 static void BlitBtoNAlphaKey(SDL_BlitInfo *info)
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397 {
398 int width = info->d_width;
399 int height = info->d_height;
400 Uint8 *src = info->s_pixels;
401 Uint8 *dst = info->d_pixels;
402 int srcskip = info->s_skip;
403 int dstskip = info->d_skip;
404 SDL_PixelFormat *srcfmt = info->src;
405 SDL_PixelFormat *dstfmt = info->dst;
406 const SDL_Color *srcpal = srcfmt->palette->colors;
407 int dstbpp;
408 int c;
409 const int A = srcfmt->alpha;
410 Uint32 ckey = srcfmt->colorkey;
411
412 /* Set up some basic variables */
413 dstbpp = dstfmt->BytesPerPixel;
414 srcskip += width-(width+7)/8;
415
416 while ( height-- ) {
417 Uint8 byte = 0, bit;
418 for ( c=0; c<width; ++c ) {
419 if ( (c%8) == 0 ) {
420 byte = *src++;
421 }
422 bit = (byte&0x80)>>7;
423 if ( bit != ckey ) {
424 int sR, sG, sB;
425 int dR, dG, dB;
426 Uint32 pixel;
427 sR = srcpal[bit].r;
428 sG = srcpal[bit].g;
429 sB = srcpal[bit].b;
430 DISEMBLE_RGB(dst, dstbpp, dstfmt,
431 pixel, dR, dG, dB);
432 ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
433 ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
434 }
435 byte <<= 1;
436 dst += dstbpp;
437 }
438 src += srcskip;
439 dst += dstskip;
440 }
441 }
442
443 static SDL_loblit bitmap_blit[] = {
444 NULL, BlitBto1, BlitBto2, BlitBto3, BlitBto4
445 };
446
447 static SDL_loblit colorkey_blit[] = {
448 NULL, BlitBto1Key, BlitBto2Key, BlitBto3Key, BlitBto4Key
449 };
450
451 SDL_loblit SDL_CalculateBlit0(SDL_Surface *surface, int blit_index)
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452 {
453 int which;
454
455 if ( surface->map->dst->format->BitsPerPixel < 8 ) {
456 which = 0;
457 } else {
458 which = surface->map->dst->format->BytesPerPixel;
459 }
460 switch(blit_index) {
461 case 0: /* copy */
462 return bitmap_blit[which];
463
464 case 1: /* colorkey */
465 return colorkey_blit[which];
466
467 case 2: /* alpha */
468 return which >= 2 ? BlitBtoNAlpha : NULL;
469
470 case 4: /* alpha + colorkey */
471 return which >= 2 ? BlitBtoNAlphaKey : NULL;
472 }
473 return NULL;
474 }
475