Mercurial > sdl-ios-xcode
annotate src/video/SDL_bmp.c @ 438:f9c5f135a8b9
Added a way to get the Windows OpenGL context in SDL_syswm.h
author | Sam Lantinga <slouken@libsdl.org> |
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date | Sat, 17 Aug 2002 17:49:27 +0000 |
parents | f6ffac90895c |
children | b8d311d90021 |
rev | line source |
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0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
297
f6ffac90895c
Updated copyright information for 2002
Sam Lantinga <slouken@libsdl.org>
parents:
252
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changeset
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3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga |
0 | 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 | |
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
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20 slouken@libsdl.org |
0 | 21 */ |
22 | |
23 #ifdef SAVE_RCSID | |
24 static char rcsid = | |
25 "@(#) $Id$"; | |
26 #endif | |
27 | |
28 #ifndef DISABLE_FILE | |
29 | |
30 /* | |
31 Code to load and save surfaces in Windows BMP format. | |
32 | |
33 Why support BMP format? Well, it's a native format for Windows, and | |
34 most image processing programs can read and write it. It would be nice | |
35 to be able to have at least one image format that we can natively load | |
36 and save, and since PNG is so complex that it would bloat the library, | |
37 BMP is a good alternative. | |
38 | |
39 This code currently supports Win32 DIBs in uncompressed 8 and 24 bpp. | |
40 */ | |
41 | |
42 #include <string.h> | |
43 | |
44 #include "SDL_error.h" | |
45 #include "SDL_video.h" | |
46 #include "SDL_endian.h" | |
47 | |
48 /* Compression encodings for BMP files */ | |
49 #ifndef BI_RGB | |
50 #define BI_RGB 0 | |
51 #define BI_RLE8 1 | |
52 #define BI_RLE4 2 | |
53 #define BI_BITFIELDS 3 | |
54 #endif | |
55 | |
56 | |
57 SDL_Surface * SDL_LoadBMP_RW (SDL_RWops *src, int freesrc) | |
58 { | |
59 int was_error; | |
60 long fp_offset; | |
61 int bmpPitch; | |
62 int i, pad; | |
63 SDL_Surface *surface; | |
64 Uint32 Rmask; | |
65 Uint32 Gmask; | |
66 Uint32 Bmask; | |
67 SDL_Palette *palette; | |
68 Uint8 *bits; | |
69 int ExpandBMP; | |
70 | |
71 /* The Win32 BMP file header (14 bytes) */ | |
72 char magic[2]; | |
73 Uint32 bfSize; | |
74 Uint16 bfReserved1; | |
75 Uint16 bfReserved2; | |
76 Uint32 bfOffBits; | |
77 | |
78 /* The Win32 BITMAPINFOHEADER struct (40 bytes) */ | |
79 Uint32 biSize; | |
80 Sint32 biWidth; | |
81 Sint32 biHeight; | |
82 Uint16 biPlanes; | |
83 Uint16 biBitCount; | |
84 Uint32 biCompression; | |
85 Uint32 biSizeImage; | |
86 Sint32 biXPelsPerMeter; | |
87 Sint32 biYPelsPerMeter; | |
88 Uint32 biClrUsed; | |
89 Uint32 biClrImportant; | |
90 | |
91 /* Make sure we are passed a valid data source */ | |
92 surface = NULL; | |
93 was_error = 0; | |
94 if ( src == NULL ) { | |
95 was_error = 1; | |
96 goto done; | |
97 } | |
98 | |
99 /* Read in the BMP file header */ | |
100 fp_offset = SDL_RWtell(src); | |
101 SDL_ClearError(); | |
102 if ( SDL_RWread(src, magic, 1, 2) != 2 ) { | |
103 SDL_Error(SDL_EFREAD); | |
104 was_error = 1; | |
105 goto done; | |
106 } | |
107 if ( strncmp(magic, "BM", 2) != 0 ) { | |
108 SDL_SetError("File is not a Windows BMP file"); | |
109 was_error = 1; | |
110 goto done; | |
111 } | |
112 bfSize = SDL_ReadLE32(src); | |
113 bfReserved1 = SDL_ReadLE16(src); | |
114 bfReserved2 = SDL_ReadLE16(src); | |
115 bfOffBits = SDL_ReadLE32(src); | |
116 | |
117 /* Read the Win32 BITMAPINFOHEADER */ | |
118 biSize = SDL_ReadLE32(src); | |
119 if ( biSize == 12 ) { | |
120 biWidth = (Uint32)SDL_ReadLE16(src); | |
121 biHeight = (Uint32)SDL_ReadLE16(src); | |
122 biPlanes = SDL_ReadLE16(src); | |
123 biBitCount = SDL_ReadLE16(src); | |
124 biCompression = BI_RGB; | |
125 biSizeImage = 0; | |
126 biXPelsPerMeter = 0; | |
127 biYPelsPerMeter = 0; | |
128 biClrUsed = 0; | |
129 biClrImportant = 0; | |
130 } else { | |
131 biWidth = SDL_ReadLE32(src); | |
132 biHeight = SDL_ReadLE32(src); | |
133 biPlanes = SDL_ReadLE16(src); | |
134 biBitCount = SDL_ReadLE16(src); | |
135 biCompression = SDL_ReadLE32(src); | |
136 biSizeImage = SDL_ReadLE32(src); | |
137 biXPelsPerMeter = SDL_ReadLE32(src); | |
138 biYPelsPerMeter = SDL_ReadLE32(src); | |
139 biClrUsed = SDL_ReadLE32(src); | |
140 biClrImportant = SDL_ReadLE32(src); | |
141 } | |
142 | |
143 /* Check for read error */ | |
144 if ( strcmp(SDL_GetError(), "") != 0 ) { | |
145 was_error = 1; | |
146 goto done; | |
147 } | |
148 | |
149 /* Expand 1 and 4 bit bitmaps to 8 bits per pixel */ | |
150 switch (biBitCount) { | |
151 case 1: | |
152 case 4: | |
153 ExpandBMP = biBitCount; | |
154 biBitCount = 8; | |
155 break; | |
156 default: | |
157 ExpandBMP = 0; | |
158 break; | |
159 } | |
160 | |
161 /* We don't support any BMP compression right now */ | |
162 Rmask = Gmask = Bmask = 0; | |
163 switch (biCompression) { | |
164 case BI_RGB: | |
165 /* If there are no masks, use the defaults */ | |
166 if ( bfOffBits == (14+biSize) ) { | |
167 /* Default values for the BMP format */ | |
168 switch (biBitCount) { | |
169 case 15: | |
170 case 16: | |
171 Rmask = 0x7C00; | |
172 Gmask = 0x03E0; | |
173 Bmask = 0x001F; | |
174 break; | |
175 case 24: | |
176 #if SDL_BYTEORDER == SDL_BIG_ENDIAN | |
177 Rmask = 0x000000FF; | |
178 Gmask = 0x0000FF00; | |
179 Bmask = 0x00FF0000; | |
180 break; | |
181 #endif | |
182 case 32: | |
183 Rmask = 0x00FF0000; | |
184 Gmask = 0x0000FF00; | |
185 Bmask = 0x000000FF; | |
186 break; | |
187 default: | |
188 break; | |
189 } | |
190 break; | |
191 } | |
192 /* Fall through -- read the RGB masks */ | |
193 | |
194 case BI_BITFIELDS: | |
195 switch (biBitCount) { | |
196 case 15: | |
197 case 16: | |
198 case 32: | |
199 Rmask = SDL_ReadLE32(src); | |
200 Gmask = SDL_ReadLE32(src); | |
201 Bmask = SDL_ReadLE32(src); | |
202 break; | |
203 default: | |
204 break; | |
205 } | |
206 break; | |
207 default: | |
208 SDL_SetError("Compressed BMP files not supported"); | |
209 was_error = 1; | |
210 goto done; | |
211 } | |
212 | |
213 /* Create a compatible surface, note that the colors are RGB ordered */ | |
214 surface = SDL_CreateRGBSurface(SDL_SWSURFACE, | |
215 biWidth, biHeight, biBitCount, Rmask, Gmask, Bmask, 0); | |
216 if ( surface == NULL ) { | |
217 was_error = 1; | |
218 goto done; | |
219 } | |
220 | |
221 /* Load the palette, if any */ | |
222 palette = (surface->format)->palette; | |
223 if ( palette ) { | |
224 if ( biClrUsed == 0 ) { | |
225 biClrUsed = 1 << biBitCount; | |
226 } | |
227 if ( biSize == 12 ) { | |
228 for ( i = 0; i < (int)biClrUsed; ++i ) { | |
229 SDL_RWread(src, &palette->colors[i].b, 1, 1); | |
230 SDL_RWread(src, &palette->colors[i].g, 1, 1); | |
231 SDL_RWread(src, &palette->colors[i].r, 1, 1); | |
232 palette->colors[i].unused = 0; | |
233 } | |
234 } else { | |
235 for ( i = 0; i < (int)biClrUsed; ++i ) { | |
236 SDL_RWread(src, &palette->colors[i].b, 1, 1); | |
237 SDL_RWread(src, &palette->colors[i].g, 1, 1); | |
238 SDL_RWread(src, &palette->colors[i].r, 1, 1); | |
239 SDL_RWread(src, &palette->colors[i].unused, 1, 1); | |
240 } | |
241 } | |
242 palette->ncolors = biClrUsed; | |
243 } | |
244 | |
245 /* Read the surface pixels. Note that the bmp image is upside down */ | |
246 if ( SDL_RWseek(src, fp_offset+bfOffBits, SEEK_SET) < 0 ) { | |
247 SDL_Error(SDL_EFSEEK); | |
248 was_error = 1; | |
249 goto done; | |
250 } | |
251 bits = (Uint8 *)surface->pixels+(surface->h*surface->pitch); | |
252 switch (ExpandBMP) { | |
253 case 1: | |
254 bmpPitch = (biWidth + 7) >> 3; | |
255 pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0); | |
256 break; | |
257 case 4: | |
258 bmpPitch = (biWidth + 1) >> 1; | |
259 pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0); | |
260 break; | |
261 default: | |
262 pad = ((surface->pitch%4) ? | |
263 (4-(surface->pitch%4)) : 0); | |
264 break; | |
265 } | |
266 while ( bits > (Uint8 *)surface->pixels ) { | |
267 bits -= surface->pitch; | |
268 switch (ExpandBMP) { | |
269 case 1: | |
270 case 4: { | |
271 Uint8 pixel = 0; | |
272 int shift = (8-ExpandBMP); | |
273 for ( i=0; i<surface->w; ++i ) { | |
274 if ( i%(8/ExpandBMP) == 0 ) { | |
275 if ( !SDL_RWread(src, &pixel, 1, 1) ) { | |
276 SDL_SetError( | |
277 "Error reading from BMP"); | |
278 was_error = 1; | |
279 goto done; | |
280 } | |
281 } | |
282 *(bits+i) = (pixel>>shift); | |
283 pixel <<= ExpandBMP; | |
284 } } | |
285 break; | |
286 | |
287 default: | |
288 if ( SDL_RWread(src, bits, 1, surface->pitch) | |
289 != surface->pitch ) { | |
290 SDL_Error(SDL_EFREAD); | |
291 was_error = 1; | |
292 goto done; | |
293 } | |
294 #if SDL_BYTEORDER == SDL_BIG_ENDIAN | |
295 /* Byte-swap the pixels if needed. Note that the 24bpp | |
296 case has already been taken care of above. */ | |
297 switch(biBitCount) { | |
298 case 15: | |
299 case 16: { | |
300 Uint16 *pix = (Uint16 *)bits; | |
301 for(i = 0; i < surface->w; i++) | |
302 pix[i] = SDL_Swap16(pix[i]); | |
303 break; | |
304 } | |
305 | |
306 case 32: { | |
307 Uint32 *pix = (Uint32 *)bits; | |
308 for(i = 0; i < surface->w; i++) | |
309 pix[i] = SDL_Swap32(pix[i]); | |
310 break; | |
311 } | |
312 } | |
313 #endif | |
314 break; | |
315 } | |
316 /* Skip padding bytes, ugh */ | |
317 if ( pad ) { | |
318 Uint8 padbyte; | |
319 for ( i=0; i<pad; ++i ) { | |
320 SDL_RWread(src, &padbyte, 1, 1); | |
321 } | |
322 } | |
323 } | |
324 done: | |
325 if ( was_error ) { | |
326 if ( surface ) { | |
327 SDL_FreeSurface(surface); | |
328 } | |
329 surface = NULL; | |
330 } | |
331 if ( freesrc && src ) { | |
332 SDL_RWclose(src); | |
333 } | |
334 return(surface); | |
335 } | |
336 | |
337 int SDL_SaveBMP_RW (SDL_Surface *saveme, SDL_RWops *dst, int freedst) | |
338 { | |
339 long fp_offset; | |
340 int i, pad; | |
341 SDL_Surface *surface; | |
342 Uint8 *bits; | |
343 | |
344 /* The Win32 BMP file header (14 bytes) */ | |
345 char magic[2] = { 'B', 'M' }; | |
346 Uint32 bfSize; | |
347 Uint16 bfReserved1; | |
348 Uint16 bfReserved2; | |
349 Uint32 bfOffBits; | |
350 | |
351 /* The Win32 BITMAPINFOHEADER struct (40 bytes) */ | |
352 Uint32 biSize; | |
353 Sint32 biWidth; | |
354 Sint32 biHeight; | |
355 Uint16 biPlanes; | |
356 Uint16 biBitCount; | |
357 Uint32 biCompression; | |
358 Uint32 biSizeImage; | |
359 Sint32 biXPelsPerMeter; | |
360 Sint32 biYPelsPerMeter; | |
361 Uint32 biClrUsed; | |
362 Uint32 biClrImportant; | |
363 | |
364 /* Make sure we have somewhere to save */ | |
365 surface = NULL; | |
366 if ( dst ) { | |
367 if ( saveme->format->palette ) { | |
368 if ( saveme->format->BitsPerPixel == 8 ) { | |
369 surface = saveme; | |
370 } else { | |
371 SDL_SetError("%d bpp BMP files not supported", | |
372 saveme->format->BitsPerPixel); | |
373 } | |
374 } | |
375 else if ( (saveme->format->BitsPerPixel == 24) && | |
376 #if SDL_BYTEORDER == SDL_LIL_ENDIAN | |
377 (saveme->format->Rmask == 0x00FF0000) && | |
378 (saveme->format->Gmask == 0x0000FF00) && | |
379 (saveme->format->Bmask == 0x000000FF) | |
380 #else | |
381 (saveme->format->Rmask == 0x000000FF) && | |
382 (saveme->format->Gmask == 0x0000FF00) && | |
383 (saveme->format->Bmask == 0x00FF0000) | |
384 #endif | |
385 ) { | |
386 surface = saveme; | |
387 } else { | |
388 SDL_Rect bounds; | |
389 | |
390 /* Convert to 24 bits per pixel */ | |
391 surface = SDL_CreateRGBSurface(SDL_SWSURFACE, | |
392 saveme->w, saveme->h, 24, | |
393 #if SDL_BYTEORDER == SDL_LIL_ENDIAN | |
394 0x00FF0000, 0x0000FF00, 0x000000FF, | |
395 #else | |
396 0x000000FF, 0x0000FF00, 0x00FF0000, | |
397 #endif | |
398 0); | |
399 if ( surface != NULL ) { | |
400 bounds.x = 0; | |
401 bounds.y = 0; | |
402 bounds.w = saveme->w; | |
403 bounds.h = saveme->h; | |
404 if ( SDL_LowerBlit(saveme, &bounds, surface, | |
405 &bounds) < 0 ) { | |
406 SDL_FreeSurface(surface); | |
407 SDL_SetError( | |
408 "Couldn't convert image to 24 bpp"); | |
409 surface = NULL; | |
410 } | |
411 } | |
412 } | |
413 } | |
414 | |
415 if ( surface && (SDL_LockSurface(surface) == 0) ) { | |
416 /* Set the BMP file header values */ | |
417 bfSize = 0; /* We'll write this when we're done */ | |
418 bfReserved1 = 0; | |
419 bfReserved2 = 0; | |
420 bfOffBits = 0; /* We'll write this when we're done */ | |
421 | |
422 /* Write the BMP file header values */ | |
423 fp_offset = SDL_RWtell(dst); | |
424 SDL_ClearError(); | |
425 SDL_RWwrite(dst, magic, 2, 1); | |
426 SDL_WriteLE32(dst, bfSize); | |
427 SDL_WriteLE16(dst, bfReserved1); | |
428 SDL_WriteLE16(dst, bfReserved2); | |
429 SDL_WriteLE32(dst, bfOffBits); | |
430 | |
431 /* Set the BMP info values */ | |
432 biSize = 40; | |
433 biWidth = surface->w; | |
434 biHeight = surface->h; | |
435 biPlanes = 1; | |
436 biBitCount = surface->format->BitsPerPixel; | |
437 biCompression = BI_RGB; | |
438 biSizeImage = surface->h*surface->pitch; | |
439 biXPelsPerMeter = 0; | |
440 biYPelsPerMeter = 0; | |
441 if ( surface->format->palette ) { | |
442 biClrUsed = surface->format->palette->ncolors; | |
443 } else { | |
444 biClrUsed = 0; | |
445 } | |
446 biClrImportant = 0; | |
447 | |
448 /* Write the BMP info values */ | |
449 SDL_WriteLE32(dst, biSize); | |
450 SDL_WriteLE32(dst, biWidth); | |
451 SDL_WriteLE32(dst, biHeight); | |
452 SDL_WriteLE16(dst, biPlanes); | |
453 SDL_WriteLE16(dst, biBitCount); | |
454 SDL_WriteLE32(dst, biCompression); | |
455 SDL_WriteLE32(dst, biSizeImage); | |
456 SDL_WriteLE32(dst, biXPelsPerMeter); | |
457 SDL_WriteLE32(dst, biYPelsPerMeter); | |
458 SDL_WriteLE32(dst, biClrUsed); | |
459 SDL_WriteLE32(dst, biClrImportant); | |
460 | |
461 /* Write the palette (in BGR color order) */ | |
462 if ( surface->format->palette ) { | |
463 SDL_Color *colors; | |
464 int ncolors; | |
465 | |
466 colors = surface->format->palette->colors; | |
467 ncolors = surface->format->palette->ncolors; | |
468 for ( i=0; i<ncolors; ++i ) { | |
469 SDL_RWwrite(dst, &colors[i].b, 1, 1); | |
470 SDL_RWwrite(dst, &colors[i].g, 1, 1); | |
471 SDL_RWwrite(dst, &colors[i].r, 1, 1); | |
472 SDL_RWwrite(dst, &colors[i].unused, 1, 1); | |
473 } | |
474 } | |
475 | |
476 /* Write the bitmap offset */ | |
477 bfOffBits = SDL_RWtell(dst)-fp_offset; | |
478 if ( SDL_RWseek(dst, fp_offset+10, SEEK_SET) < 0 ) { | |
479 SDL_Error(SDL_EFSEEK); | |
480 } | |
481 SDL_WriteLE32(dst, bfOffBits); | |
482 if ( SDL_RWseek(dst, fp_offset+bfOffBits, SEEK_SET) < 0 ) { | |
483 SDL_Error(SDL_EFSEEK); | |
484 } | |
485 | |
486 /* Write the bitmap image upside down */ | |
487 bits = (Uint8 *)surface->pixels+(surface->h*surface->pitch); | |
488 pad = ((surface->pitch%4) ? (4-(surface->pitch%4)) : 0); | |
489 while ( bits > (Uint8 *)surface->pixels ) { | |
490 bits -= surface->pitch; | |
491 if ( SDL_RWwrite(dst, bits, 1, surface->pitch) | |
492 != surface->pitch) { | |
493 SDL_Error(SDL_EFWRITE); | |
494 break; | |
495 } | |
496 if ( pad ) { | |
497 const Uint8 padbyte = 0; | |
498 for ( i=0; i<pad; ++i ) { | |
499 SDL_RWwrite(dst, &padbyte, 1, 1); | |
500 } | |
501 } | |
502 } | |
503 | |
504 /* Write the BMP file size */ | |
505 bfSize = SDL_RWtell(dst)-fp_offset; | |
506 if ( SDL_RWseek(dst, fp_offset+2, SEEK_SET) < 0 ) { | |
507 SDL_Error(SDL_EFSEEK); | |
508 } | |
509 SDL_WriteLE32(dst, bfSize); | |
510 if ( SDL_RWseek(dst, fp_offset+bfSize, SEEK_SET) < 0 ) { | |
511 SDL_Error(SDL_EFSEEK); | |
512 } | |
513 | |
514 /* Close it up.. */ | |
515 SDL_UnlockSurface(surface); | |
516 if ( surface != saveme ) { | |
517 SDL_FreeSurface(surface); | |
518 } | |
519 } | |
520 | |
521 if ( freedst && dst ) { | |
522 SDL_RWclose(dst); | |
523 } | |
524 return((strcmp(SDL_GetError(), "") == 0) ? 0 : -1); | |
525 } | |
526 | |
527 #endif /* ENABLE_FILE */ |