Mercurial > sdl-ios-xcode
annotate src/video/SDL_pixels.c @ 946:8520712f8ef0
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author | Sam Lantinga <slouken@libsdl.org> |
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date | Sat, 21 Aug 2004 14:54:49 +0000 |
parents | 333db1d87876 |
children | 3bf4103b2b89 |
rev | line source |
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0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
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Updated copyright information for 2004 (Happy New Year!)
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3 Copyright (C) 1997-2004 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 | |
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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 /* General (mostly internal) pixel/color manipulation routines for SDL */ | |
29 | |
30 #include <stdio.h> | |
31 #include <stdlib.h> | |
32 #include <string.h> | |
33 | |
34 #include "SDL_error.h" | |
35 #include "SDL_endian.h" | |
36 #include "SDL_video.h" | |
37 #include "SDL_sysvideo.h" | |
38 #include "SDL_blit.h" | |
39 #include "SDL_pixels_c.h" | |
40 #include "SDL_RLEaccel_c.h" | |
41 | |
42 /* Helper functions */ | |
43 /* | |
44 * Allocate a pixel format structure and fill it according to the given info. | |
45 */ | |
46 SDL_PixelFormat *SDL_AllocFormat(int bpp, | |
47 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) | |
48 { | |
49 SDL_PixelFormat *format; | |
50 Uint32 mask; | |
51 | |
52 /* Allocate an empty pixel format structure */ | |
53 format = malloc(sizeof(*format)); | |
54 if ( format == NULL ) { | |
55 SDL_OutOfMemory(); | |
56 return(NULL); | |
57 } | |
58 memset(format, 0, sizeof(*format)); | |
59 format->alpha = SDL_ALPHA_OPAQUE; | |
60 | |
61 /* Set up the format */ | |
62 format->BitsPerPixel = bpp; | |
63 format->BytesPerPixel = (bpp+7)/8; | |
64 switch (bpp) { | |
65 case 1: | |
66 /* Create the 2 color black-white palette */ | |
67 format->palette = (SDL_Palette *)malloc( | |
68 sizeof(SDL_Palette)); | |
69 if ( format->palette == NULL ) { | |
70 SDL_FreeFormat(format); | |
71 SDL_OutOfMemory(); | |
72 return(NULL); | |
73 } | |
74 (format->palette)->ncolors = 2; | |
75 (format->palette)->colors = (SDL_Color *)malloc( | |
76 (format->palette)->ncolors*sizeof(SDL_Color)); | |
77 if ( (format->palette)->colors == NULL ) { | |
78 SDL_FreeFormat(format); | |
79 SDL_OutOfMemory(); | |
80 return(NULL); | |
81 } | |
82 format->palette->colors[0].r = 0xFF; | |
83 format->palette->colors[0].g = 0xFF; | |
84 format->palette->colors[0].b = 0xFF; | |
85 format->palette->colors[1].r = 0x00; | |
86 format->palette->colors[1].g = 0x00; | |
87 format->palette->colors[1].b = 0x00; | |
88 format->Rloss = 8; | |
89 format->Gloss = 8; | |
90 format->Bloss = 8; | |
91 format->Aloss = 8; | |
92 format->Rshift = 0; | |
93 format->Gshift = 0; | |
94 format->Bshift = 0; | |
95 format->Ashift = 0; | |
96 format->Rmask = 0; | |
97 format->Gmask = 0; | |
98 format->Bmask = 0; | |
99 format->Amask = 0; | |
100 break; | |
101 | |
102 case 4: | |
103 /* Create the 16 color VGA palette */ | |
104 format->palette = (SDL_Palette *)malloc( | |
105 sizeof(SDL_Palette)); | |
106 if ( format->palette == NULL ) { | |
107 SDL_FreeFormat(format); | |
108 SDL_OutOfMemory(); | |
109 return(NULL); | |
110 } | |
111 (format->palette)->ncolors = 16; | |
112 (format->palette)->colors = (SDL_Color *)malloc( | |
113 (format->palette)->ncolors*sizeof(SDL_Color)); | |
114 if ( (format->palette)->colors == NULL ) { | |
115 SDL_FreeFormat(format); | |
116 SDL_OutOfMemory(); | |
117 return(NULL); | |
118 } | |
119 /* Punt for now, will this ever be used? */ | |
120 memset((format->palette)->colors, 0, | |
121 (format->palette)->ncolors*sizeof(SDL_Color)); | |
122 | |
123 /* Palettized formats have no mask info */ | |
124 format->Rloss = 8; | |
125 format->Gloss = 8; | |
126 format->Bloss = 8; | |
127 format->Aloss = 8; | |
128 format->Rshift = 0; | |
129 format->Gshift = 0; | |
130 format->Bshift = 0; | |
131 format->Ashift = 0; | |
132 format->Rmask = 0; | |
133 format->Gmask = 0; | |
134 format->Bmask = 0; | |
135 format->Amask = 0; | |
136 break; | |
137 | |
138 case 8: | |
139 /* Create an empty 256 color palette */ | |
140 format->palette = (SDL_Palette *)malloc( | |
141 sizeof(SDL_Palette)); | |
142 if ( format->palette == NULL ) { | |
143 SDL_FreeFormat(format); | |
144 SDL_OutOfMemory(); | |
145 return(NULL); | |
146 } | |
147 (format->palette)->ncolors = 256; | |
148 (format->palette)->colors = (SDL_Color *)malloc( | |
149 (format->palette)->ncolors*sizeof(SDL_Color)); | |
150 if ( (format->palette)->colors == NULL ) { | |
151 SDL_FreeFormat(format); | |
152 SDL_OutOfMemory(); | |
153 return(NULL); | |
154 } | |
155 memset((format->palette)->colors, 0, | |
156 (format->palette)->ncolors*sizeof(SDL_Color)); | |
157 | |
158 /* Palettized formats have no mask info */ | |
159 format->Rloss = 8; | |
160 format->Gloss = 8; | |
161 format->Bloss = 8; | |
162 format->Aloss = 8; | |
163 format->Rshift = 0; | |
164 format->Gshift = 0; | |
165 format->Bshift = 0; | |
166 format->Ashift = 0; | |
167 format->Rmask = 0; | |
168 format->Gmask = 0; | |
169 format->Bmask = 0; | |
170 format->Amask = 0; | |
171 break; | |
172 | |
173 default: | |
174 /* No palette, just packed pixel info */ | |
175 format->palette = NULL; | |
176 format->Rshift = 0; | |
177 format->Rloss = 8; | |
178 if ( Rmask ) { | |
179 for ( mask = Rmask; !(mask&0x01); mask >>= 1 ) | |
180 ++format->Rshift; | |
181 for ( ; (mask&0x01); mask >>= 1 ) | |
182 --format->Rloss; | |
183 } | |
184 format->Gshift = 0; | |
185 format->Gloss = 8; | |
186 if ( Gmask ) { | |
187 for ( mask = Gmask; !(mask&0x01); mask >>= 1 ) | |
188 ++format->Gshift; | |
189 for ( ; (mask&0x01); mask >>= 1 ) | |
190 --format->Gloss; | |
191 } | |
192 format->Bshift = 0; | |
193 format->Bloss = 8; | |
194 if ( Bmask ) { | |
195 for ( mask = Bmask; !(mask&0x01); mask >>= 1 ) | |
196 ++format->Bshift; | |
197 for ( ; (mask&0x01); mask >>= 1 ) | |
198 --format->Bloss; | |
199 } | |
200 format->Ashift = 0; | |
201 format->Aloss = 8; | |
202 if ( Amask ) { | |
203 for ( mask = Amask; !(mask&0x01); mask >>= 1 ) | |
204 ++format->Ashift; | |
205 for ( ; (mask&0x01); mask >>= 1 ) | |
206 --format->Aloss; | |
207 } | |
208 format->Rmask = Rmask; | |
209 format->Gmask = Gmask; | |
210 format->Bmask = Bmask; | |
211 format->Amask = Amask; | |
212 break; | |
213 } | |
214 /* Calculate some standard bitmasks, if necessary | |
215 * Note: This could conflict with an alpha mask, if given. | |
216 */ | |
217 if ( (bpp > 8) && !format->Rmask && !format->Gmask && !format->Bmask ) { | |
218 /* R-G-B */ | |
219 if ( bpp > 24 ) | |
220 bpp = 24; | |
221 format->Rloss = 8-(bpp/3); | |
222 format->Gloss = 8-(bpp/3)-(bpp%3); | |
223 format->Bloss = 8-(bpp/3); | |
224 format->Rshift = ((bpp/3)+(bpp%3))+(bpp/3); | |
225 format->Gshift = (bpp/3); | |
226 format->Bshift = 0; | |
227 format->Rmask = ((0xFF>>format->Rloss)<<format->Rshift); | |
228 format->Gmask = ((0xFF>>format->Gloss)<<format->Gshift); | |
229 format->Bmask = ((0xFF>>format->Bloss)<<format->Bshift); | |
230 } | |
231 return(format); | |
232 } | |
233 SDL_PixelFormat *SDL_ReallocFormat(SDL_Surface *surface, int bpp, | |
234 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) | |
235 { | |
236 if ( surface->format ) { | |
237 SDL_FreeFormat(surface->format); | |
238 SDL_FormatChanged(surface); | |
239 } | |
240 surface->format = SDL_AllocFormat(bpp, Rmask, Gmask, Bmask, Amask); | |
241 return surface->format; | |
242 } | |
243 | |
244 /* | |
245 * Change any previous mappings from/to the new surface format | |
246 */ | |
247 void SDL_FormatChanged(SDL_Surface *surface) | |
248 { | |
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249 static int format_version = 0; |
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250 ++format_version; |
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251 if ( format_version < 0 ) { /* It wrapped... */ |
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252 format_version = 1; |
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253 } |
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254 surface->format_version = format_version; |
0 | 255 SDL_InvalidateMap(surface->map); |
256 } | |
257 /* | |
258 * Free a previously allocated format structure | |
259 */ | |
260 void SDL_FreeFormat(SDL_PixelFormat *format) | |
261 { | |
262 if ( format ) { | |
263 if ( format->palette ) { | |
264 if ( format->palette->colors ) { | |
265 free(format->palette->colors); | |
266 } | |
267 free(format->palette); | |
268 } | |
269 free(format); | |
270 } | |
271 } | |
272 /* | |
273 * Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors | |
274 */ | |
275 void SDL_DitherColors(SDL_Color *colors, int bpp) | |
276 { | |
277 int i; | |
278 if(bpp != 8) | |
279 return; /* only 8bpp supported right now */ | |
280 | |
281 for(i = 0; i < 256; i++) { | |
282 int r, g, b; | |
283 /* map each bit field to the full [0, 255] interval, | |
284 so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */ | |
285 r = i & 0xe0; | |
286 r |= r >> 3 | r >> 6; | |
287 colors[i].r = r; | |
288 g = (i << 3) & 0xe0; | |
289 g |= g >> 3 | g >> 6; | |
290 colors[i].g = g; | |
291 b = i & 0x3; | |
292 b |= b << 2; | |
293 b |= b << 4; | |
294 colors[i].b = b; | |
295 } | |
296 } | |
297 /* | |
298 * Calculate the pad-aligned scanline width of a surface | |
299 */ | |
300 Uint16 SDL_CalculatePitch(SDL_Surface *surface) | |
301 { | |
302 Uint16 pitch; | |
303 | |
304 /* Surface should be 4-byte aligned for speed */ | |
305 pitch = surface->w*surface->format->BytesPerPixel; | |
306 switch (surface->format->BitsPerPixel) { | |
307 case 1: | |
308 pitch = (pitch+7)/8; | |
309 break; | |
310 case 4: | |
311 pitch = (pitch+1)/2; | |
312 break; | |
313 default: | |
314 break; | |
315 } | |
316 pitch = (pitch + 3) & ~3; /* 4-byte aligning */ | |
317 return(pitch); | |
318 } | |
319 /* | |
320 * Match an RGB value to a particular palette index | |
321 */ | |
322 Uint8 SDL_FindColor(SDL_Palette *pal, Uint8 r, Uint8 g, Uint8 b) | |
323 { | |
324 /* Do colorspace distance matching */ | |
325 unsigned int smallest; | |
326 unsigned int distance; | |
327 int rd, gd, bd; | |
328 int i; | |
329 Uint8 pixel=0; | |
330 | |
331 smallest = ~0; | |
332 for ( i=0; i<pal->ncolors; ++i ) { | |
333 rd = pal->colors[i].r - r; | |
334 gd = pal->colors[i].g - g; | |
335 bd = pal->colors[i].b - b; | |
336 distance = (rd*rd)+(gd*gd)+(bd*bd); | |
337 if ( distance < smallest ) { | |
338 pixel = i; | |
339 if ( distance == 0 ) { /* Perfect match! */ | |
340 break; | |
341 } | |
342 smallest = distance; | |
343 } | |
344 } | |
345 return(pixel); | |
346 } | |
347 | |
348 /* Find the opaque pixel value corresponding to an RGB triple */ | |
349 Uint32 SDL_MapRGB(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b) | |
350 { | |
351 if ( format->palette == NULL ) { | |
352 return (r >> format->Rloss) << format->Rshift | |
353 | (g >> format->Gloss) << format->Gshift | |
354 | (b >> format->Bloss) << format->Bshift | |
355 | format->Amask; | |
356 } else { | |
357 return SDL_FindColor(format->palette, r, g, b); | |
358 } | |
359 } | |
360 | |
361 /* Find the pixel value corresponding to an RGBA quadruple */ | |
362 Uint32 SDL_MapRGBA(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b, Uint8 a) | |
363 { | |
364 if ( format->palette == NULL ) { | |
365 return (r >> format->Rloss) << format->Rshift | |
366 | (g >> format->Gloss) << format->Gshift | |
367 | (b >> format->Bloss) << format->Bshift | |
368 | ((a >> format->Aloss) << format->Ashift & format->Amask); | |
369 } else { | |
370 return SDL_FindColor(format->palette, r, g, b); | |
371 } | |
372 } | |
373 | |
374 void SDL_GetRGBA(Uint32 pixel, SDL_PixelFormat *fmt, | |
375 Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a) | |
376 { | |
377 if ( fmt->palette == NULL ) { | |
378 /* | |
379 * This makes sure that the result is mapped to the | |
380 * interval [0..255], and the maximum value for each | |
381 * component is 255. This is important to make sure | |
382 * that white is indeed reported as (255, 255, 255), | |
383 * and that opaque alpha is 255. | |
384 * This only works for RGB bit fields at least 4 bit | |
385 * wide, which is almost always the case. | |
386 */ | |
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387 unsigned v; |
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388 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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389 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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390 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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391 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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392 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
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393 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
0 | 394 if(fmt->Amask) { |
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395 v = (pixel & fmt->Amask) >> fmt->Ashift; |
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396 *a = (v << fmt->Aloss) + (v >> (8 - (fmt->Aloss << 1))); |
695 | 397 } else { |
0 | 398 *a = SDL_ALPHA_OPAQUE; |
695 | 399 } |
0 | 400 } else { |
401 *r = fmt->palette->colors[pixel].r; | |
402 *g = fmt->palette->colors[pixel].g; | |
403 *b = fmt->palette->colors[pixel].b; | |
404 *a = SDL_ALPHA_OPAQUE; | |
405 } | |
406 } | |
407 | |
408 void SDL_GetRGB(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r,Uint8 *g,Uint8 *b) | |
409 { | |
410 if ( fmt->palette == NULL ) { | |
411 /* the note for SDL_GetRGBA above applies here too */ | |
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412 unsigned v; |
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413 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
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414 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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415 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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416 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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417 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
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Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
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418 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
0 | 419 } else { |
420 *r = fmt->palette->colors[pixel].r; | |
421 *g = fmt->palette->colors[pixel].g; | |
422 *b = fmt->palette->colors[pixel].b; | |
423 } | |
424 } | |
425 | |
426 /* Apply gamma to a set of colors - this is easy. :) */ | |
427 void SDL_ApplyGamma(Uint16 *gamma, SDL_Color *colors, SDL_Color *output, | |
428 int ncolors) | |
429 { | |
430 int i; | |
431 | |
432 for ( i=0; i<ncolors; ++i ) { | |
433 output[i].r = gamma[0*256 + colors[i].r] >> 8; | |
434 output[i].g = gamma[1*256 + colors[i].g] >> 8; | |
435 output[i].b = gamma[2*256 + colors[i].b] >> 8; | |
436 } | |
437 } | |
438 | |
439 /* Map from Palette to Palette */ | |
440 static Uint8 *Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical) | |
441 { | |
442 Uint8 *map; | |
443 int i; | |
444 | |
445 if ( identical ) { | |
446 if ( src->ncolors <= dst->ncolors ) { | |
447 /* If an identical palette, no need to map */ | |
448 if ( memcmp(src->colors, dst->colors, src->ncolors* | |
449 sizeof(SDL_Color)) == 0 ) { | |
450 *identical = 1; | |
451 return(NULL); | |
452 } | |
453 } | |
454 *identical = 0; | |
455 } | |
456 map = (Uint8 *)malloc(src->ncolors); | |
457 if ( map == NULL ) { | |
458 SDL_OutOfMemory(); | |
459 return(NULL); | |
460 } | |
461 for ( i=0; i<src->ncolors; ++i ) { | |
462 map[i] = SDL_FindColor(dst, | |
463 src->colors[i].r, src->colors[i].g, src->colors[i].b); | |
464 } | |
465 return(map); | |
466 } | |
467 /* Map from Palette to BitField */ | |
468 static Uint8 *Map1toN(SDL_Palette *src, SDL_PixelFormat *dst) | |
469 { | |
470 Uint8 *map; | |
471 int i; | |
472 int bpp; | |
50 | 473 unsigned alpha; |
0 | 474 |
475 bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel); | |
476 map = (Uint8 *)malloc(src->ncolors*bpp); | |
477 if ( map == NULL ) { | |
478 SDL_OutOfMemory(); | |
479 return(NULL); | |
480 } | |
481 | |
50 | 482 alpha = dst->Amask ? SDL_ALPHA_OPAQUE : 0; |
0 | 483 /* We memory copy to the pixel map so the endianness is preserved */ |
484 for ( i=0; i<src->ncolors; ++i ) { | |
485 ASSEMBLE_RGBA(&map[i*bpp], dst->BytesPerPixel, dst, | |
486 src->colors[i].r, src->colors[i].g, | |
50 | 487 src->colors[i].b, alpha); |
0 | 488 } |
489 return(map); | |
490 } | |
491 /* Map from BitField to Dithered-Palette to Palette */ | |
492 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical) | |
493 { | |
494 /* Generate a 256 color dither palette */ | |
495 SDL_Palette dithered; | |
496 SDL_Color colors[256]; | |
497 | |
498 dithered.ncolors = 256; | |
499 SDL_DitherColors(colors, 8); | |
500 dithered.colors = colors; | |
501 return(Map1to1(&dithered, dst, identical)); | |
502 } | |
503 | |
504 SDL_BlitMap *SDL_AllocBlitMap(void) | |
505 { | |
506 SDL_BlitMap *map; | |
507 | |
508 /* Allocate the empty map */ | |
509 map = (SDL_BlitMap *)malloc(sizeof(*map)); | |
510 if ( map == NULL ) { | |
511 SDL_OutOfMemory(); | |
512 return(NULL); | |
513 } | |
514 memset(map, 0, sizeof(*map)); | |
515 | |
516 /* Allocate the software blit data */ | |
517 map->sw_data = (struct private_swaccel *)malloc(sizeof(*map->sw_data)); | |
518 if ( map->sw_data == NULL ) { | |
519 SDL_FreeBlitMap(map); | |
520 SDL_OutOfMemory(); | |
521 return(NULL); | |
522 } | |
523 memset(map->sw_data, 0, sizeof(*map->sw_data)); | |
524 | |
525 /* It's ready to go */ | |
526 return(map); | |
527 } | |
528 void SDL_InvalidateMap(SDL_BlitMap *map) | |
529 { | |
530 if ( ! map ) { | |
531 return; | |
532 } | |
533 map->dst = NULL; | |
534 map->format_version = (unsigned int)-1; | |
535 if ( map->table ) { | |
536 free(map->table); | |
537 map->table = NULL; | |
538 } | |
539 } | |
540 int SDL_MapSurface (SDL_Surface *src, SDL_Surface *dst) | |
541 { | |
542 SDL_PixelFormat *srcfmt; | |
543 SDL_PixelFormat *dstfmt; | |
544 SDL_BlitMap *map; | |
545 | |
546 /* Clear out any previous mapping */ | |
547 map = src->map; | |
548 if ( (src->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { | |
549 SDL_UnRLESurface(src, 1); | |
550 } | |
551 SDL_InvalidateMap(map); | |
552 | |
553 /* Figure out what kind of mapping we're doing */ | |
554 map->identity = 0; | |
555 srcfmt = src->format; | |
556 dstfmt = dst->format; | |
557 switch (srcfmt->BytesPerPixel) { | |
558 case 1: | |
559 switch (dstfmt->BytesPerPixel) { | |
560 case 1: | |
561 /* Palette --> Palette */ | |
562 /* If both SDL_HWSURFACE, assume have same palette */ | |
563 if ( ((src->flags & SDL_HWSURFACE) == SDL_HWSURFACE) && | |
564 ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) ) { | |
565 map->identity = 1; | |
566 } else { | |
567 map->table = Map1to1(srcfmt->palette, | |
568 dstfmt->palette, &map->identity); | |
569 } | |
570 if ( ! map->identity ) { | |
571 if ( map->table == NULL ) { | |
572 return(-1); | |
573 } | |
574 } | |
575 if (srcfmt->BitsPerPixel!=dstfmt->BitsPerPixel) | |
576 map->identity = 0; | |
577 break; | |
578 | |
579 default: | |
580 /* Palette --> BitField */ | |
581 map->table = Map1toN(srcfmt->palette, dstfmt); | |
582 if ( map->table == NULL ) { | |
583 return(-1); | |
584 } | |
585 break; | |
586 } | |
587 break; | |
588 default: | |
589 switch (dstfmt->BytesPerPixel) { | |
590 case 1: | |
591 /* BitField --> Palette */ | |
592 map->table = MapNto1(srcfmt, | |
593 dstfmt->palette, &map->identity); | |
594 if ( ! map->identity ) { | |
595 if ( map->table == NULL ) { | |
596 return(-1); | |
597 } | |
598 } | |
599 map->identity = 0; /* Don't optimize to copy */ | |
600 break; | |
601 default: | |
602 /* BitField --> BitField */ | |
603 if ( FORMAT_EQUAL(srcfmt, dstfmt) ) | |
604 map->identity = 1; | |
605 break; | |
606 } | |
607 break; | |
608 } | |
609 | |
610 map->dst = dst; | |
611 map->format_version = dst->format_version; | |
612 | |
613 /* Choose your blitters wisely */ | |
614 return(SDL_CalculateBlit(src)); | |
615 } | |
616 void SDL_FreeBlitMap(SDL_BlitMap *map) | |
617 { | |
618 if ( map ) { | |
619 SDL_InvalidateMap(map); | |
620 if ( map->sw_data != NULL ) { | |
621 free(map->sw_data); | |
622 } | |
623 free(map); | |
624 } | |
625 } |