|
0
|
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 "@(#) $Id$";
|
|
|
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 {
|
|
|
249 surface->format_version++;
|
|
|
250 SDL_InvalidateMap(surface->map);
|
|
|
251 }
|
|
|
252 /*
|
|
|
253 * Free a previously allocated format structure
|
|
|
254 */
|
|
|
255 void SDL_FreeFormat(SDL_PixelFormat *format)
|
|
|
256 {
|
|
|
257 if ( format ) {
|
|
|
258 if ( format->palette ) {
|
|
|
259 if ( format->palette->colors ) {
|
|
|
260 free(format->palette->colors);
|
|
|
261 }
|
|
|
262 free(format->palette);
|
|
|
263 }
|
|
|
264 free(format);
|
|
|
265 }
|
|
|
266 }
|
|
|
267 /*
|
|
|
268 * Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors
|
|
|
269 */
|
|
|
270 void SDL_DitherColors(SDL_Color *colors, int bpp)
|
|
|
271 {
|
|
|
272 int i;
|
|
|
273 if(bpp != 8)
|
|
|
274 return; /* only 8bpp supported right now */
|
|
|
275
|
|
|
276 for(i = 0; i < 256; i++) {
|
|
|
277 int r, g, b;
|
|
|
278 /* map each bit field to the full [0, 255] interval,
|
|
|
279 so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */
|
|
|
280 r = i & 0xe0;
|
|
|
281 r |= r >> 3 | r >> 6;
|
|
|
282 colors[i].r = r;
|
|
|
283 g = (i << 3) & 0xe0;
|
|
|
284 g |= g >> 3 | g >> 6;
|
|
|
285 colors[i].g = g;
|
|
|
286 b = i & 0x3;
|
|
|
287 b |= b << 2;
|
|
|
288 b |= b << 4;
|
|
|
289 colors[i].b = b;
|
|
|
290 }
|
|
|
291 }
|
|
|
292 /*
|
|
|
293 * Calculate the pad-aligned scanline width of a surface
|
|
|
294 */
|
|
|
295 Uint16 SDL_CalculatePitch(SDL_Surface *surface)
|
|
|
296 {
|
|
|
297 Uint16 pitch;
|
|
|
298
|
|
|
299 /* Surface should be 4-byte aligned for speed */
|
|
|
300 pitch = surface->w*surface->format->BytesPerPixel;
|
|
|
301 switch (surface->format->BitsPerPixel) {
|
|
|
302 case 1:
|
|
|
303 pitch = (pitch+7)/8;
|
|
|
304 break;
|
|
|
305 case 4:
|
|
|
306 pitch = (pitch+1)/2;
|
|
|
307 break;
|
|
|
308 default:
|
|
|
309 break;
|
|
|
310 }
|
|
|
311 pitch = (pitch + 3) & ~3; /* 4-byte aligning */
|
|
|
312 return(pitch);
|
|
|
313 }
|
|
|
314 /*
|
|
|
315 * Match an RGB value to a particular palette index
|
|
|
316 */
|
|
|
317 Uint8 SDL_FindColor(SDL_Palette *pal, Uint8 r, Uint8 g, Uint8 b)
|
|
|
318 {
|
|
|
319 /* Do colorspace distance matching */
|
|
|
320 unsigned int smallest;
|
|
|
321 unsigned int distance;
|
|
|
322 int rd, gd, bd;
|
|
|
323 int i;
|
|
|
324 Uint8 pixel=0;
|
|
|
325
|
|
|
326 smallest = ~0;
|
|
|
327 for ( i=0; i<pal->ncolors; ++i ) {
|
|
|
328 rd = pal->colors[i].r - r;
|
|
|
329 gd = pal->colors[i].g - g;
|
|
|
330 bd = pal->colors[i].b - b;
|
|
|
331 distance = (rd*rd)+(gd*gd)+(bd*bd);
|
|
|
332 if ( distance < smallest ) {
|
|
|
333 pixel = i;
|
|
|
334 if ( distance == 0 ) { /* Perfect match! */
|
|
|
335 break;
|
|
|
336 }
|
|
|
337 smallest = distance;
|
|
|
338 }
|
|
|
339 }
|
|
|
340 return(pixel);
|
|
|
341 }
|
|
|
342
|
|
|
343 /* Find the opaque pixel value corresponding to an RGB triple */
|
|
|
344 Uint32 SDL_MapRGB(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b)
|
|
|
345 {
|
|
|
346 if ( format->palette == NULL ) {
|
|
|
347 return (r >> format->Rloss) << format->Rshift
|
|
|
348 | (g >> format->Gloss) << format->Gshift
|
|
|
349 | (b >> format->Bloss) << format->Bshift
|
|
|
350 | format->Amask;
|
|
|
351 } else {
|
|
|
352 return SDL_FindColor(format->palette, r, g, b);
|
|
|
353 }
|
|
|
354 }
|
|
|
355
|
|
|
356 /* Find the pixel value corresponding to an RGBA quadruple */
|
|
|
357 Uint32 SDL_MapRGBA(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
|
|
|
358 {
|
|
|
359 if ( format->palette == NULL ) {
|
|
|
360 return (r >> format->Rloss) << format->Rshift
|
|
|
361 | (g >> format->Gloss) << format->Gshift
|
|
|
362 | (b >> format->Bloss) << format->Bshift
|
|
|
363 | ((a >> format->Aloss) << format->Ashift & format->Amask);
|
|
|
364 } else {
|
|
|
365 return SDL_FindColor(format->palette, r, g, b);
|
|
|
366 }
|
|
|
367 }
|
|
|
368
|
|
|
369 void SDL_GetRGBA(Uint32 pixel, SDL_PixelFormat *fmt,
|
|
|
370 Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
|
|
|
371 {
|
|
|
372 if ( fmt->palette == NULL ) {
|
|
|
373 /*
|
|
|
374 * This makes sure that the result is mapped to the
|
|
|
375 * interval [0..255], and the maximum value for each
|
|
|
376 * component is 255. This is important to make sure
|
|
|
377 * that white is indeed reported as (255, 255, 255),
|
|
|
378 * and that opaque alpha is 255.
|
|
|
379 * This only works for RGB bit fields at least 4 bit
|
|
|
380 * wide, which is almost always the case.
|
|
|
381 */
|
|
|
382 unsigned rv, gv, bv, av;
|
|
|
383 rv = (pixel & fmt->Rmask) >> fmt->Rshift;
|
|
|
384 *r = (rv << fmt->Rloss) + (rv >> (8 - fmt->Rloss));
|
|
|
385 gv = (pixel & fmt->Gmask) >> fmt->Gshift;
|
|
|
386 *g = (gv << fmt->Gloss) + (gv >> (8 - fmt->Gloss));
|
|
|
387 bv = (pixel & fmt->Bmask) >> fmt->Bshift;
|
|
|
388 *b = (bv << fmt->Bloss) + (bv >> (8 - fmt->Bloss));
|
|
|
389 if(fmt->Amask) {
|
|
|
390 av = (pixel & fmt->Amask) >> fmt->Ashift;
|
|
|
391 *a = (av << fmt->Aloss) + (av >> (8 - fmt->Aloss));
|
|
|
392 } else
|
|
|
393 *a = SDL_ALPHA_OPAQUE;
|
|
|
394 } else {
|
|
|
395 *r = fmt->palette->colors[pixel].r;
|
|
|
396 *g = fmt->palette->colors[pixel].g;
|
|
|
397 *b = fmt->palette->colors[pixel].b;
|
|
|
398 *a = SDL_ALPHA_OPAQUE;
|
|
|
399 }
|
|
|
400 }
|
|
|
401
|
|
|
402 void SDL_GetRGB(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r,Uint8 *g,Uint8 *b)
|
|
|
403 {
|
|
|
404 if ( fmt->palette == NULL ) {
|
|
|
405 /* the note for SDL_GetRGBA above applies here too */
|
|
|
406 unsigned rv, gv, bv;
|
|
|
407 rv = (pixel & fmt->Rmask) >> fmt->Rshift;
|
|
|
408 *r = (rv << fmt->Rloss) + (rv >> (8 - fmt->Rloss));
|
|
|
409 gv = (pixel & fmt->Gmask) >> fmt->Gshift;
|
|
|
410 *g = (gv << fmt->Gloss) + (gv >> (8 - fmt->Gloss));
|
|
|
411 bv = (pixel & fmt->Bmask) >> fmt->Bshift;
|
|
|
412 *b = (bv << fmt->Bloss) + (bv >> (8 - fmt->Bloss));
|
|
|
413 } else {
|
|
|
414 *r = fmt->palette->colors[pixel].r;
|
|
|
415 *g = fmt->palette->colors[pixel].g;
|
|
|
416 *b = fmt->palette->colors[pixel].b;
|
|
|
417 }
|
|
|
418 }
|
|
|
419
|
|
|
420 /* Apply gamma to a set of colors - this is easy. :) */
|
|
|
421 void SDL_ApplyGamma(Uint16 *gamma, SDL_Color *colors, SDL_Color *output,
|
|
|
422 int ncolors)
|
|
|
423 {
|
|
|
424 int i;
|
|
|
425
|
|
|
426 for ( i=0; i<ncolors; ++i ) {
|
|
|
427 output[i].r = gamma[0*256 + colors[i].r] >> 8;
|
|
|
428 output[i].g = gamma[1*256 + colors[i].g] >> 8;
|
|
|
429 output[i].b = gamma[2*256 + colors[i].b] >> 8;
|
|
|
430 }
|
|
|
431 }
|
|
|
432
|
|
|
433 /* Map from Palette to Palette */
|
|
|
434 static Uint8 *Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical)
|
|
|
435 {
|
|
|
436 Uint8 *map;
|
|
|
437 int i;
|
|
|
438
|
|
|
439 if ( identical ) {
|
|
|
440 if ( src->ncolors <= dst->ncolors ) {
|
|
|
441 /* If an identical palette, no need to map */
|
|
|
442 if ( memcmp(src->colors, dst->colors, src->ncolors*
|
|
|
443 sizeof(SDL_Color)) == 0 ) {
|
|
|
444 *identical = 1;
|
|
|
445 return(NULL);
|
|
|
446 }
|
|
|
447 }
|
|
|
448 *identical = 0;
|
|
|
449 }
|
|
|
450 map = (Uint8 *)malloc(src->ncolors);
|
|
|
451 if ( map == NULL ) {
|
|
|
452 SDL_OutOfMemory();
|
|
|
453 return(NULL);
|
|
|
454 }
|
|
|
455 for ( i=0; i<src->ncolors; ++i ) {
|
|
|
456 map[i] = SDL_FindColor(dst,
|
|
|
457 src->colors[i].r, src->colors[i].g, src->colors[i].b);
|
|
|
458 }
|
|
|
459 return(map);
|
|
|
460 }
|
|
|
461 /* Map from Palette to BitField */
|
|
|
462 static Uint8 *Map1toN(SDL_Palette *src, SDL_PixelFormat *dst)
|
|
|
463 {
|
|
|
464 Uint8 *map;
|
|
|
465 int i;
|
|
|
466 int bpp;
|
|
|
467
|
|
|
468 bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel);
|
|
|
469 map = (Uint8 *)malloc(src->ncolors*bpp);
|
|
|
470 if ( map == NULL ) {
|
|
|
471 SDL_OutOfMemory();
|
|
|
472 return(NULL);
|
|
|
473 }
|
|
|
474
|
|
|
475 /* We memory copy to the pixel map so the endianness is preserved */
|
|
|
476 for ( i=0; i<src->ncolors; ++i ) {
|
|
|
477 ASSEMBLE_RGBA(&map[i*bpp], dst->BytesPerPixel, dst,
|
|
|
478 src->colors[i].r, src->colors[i].g,
|
|
48
|
479 src->colors[i].b, SDL_ALPHA_OPAQUE);
|
|
0
|
480 }
|
|
|
481 return(map);
|
|
|
482 }
|
|
|
483 /* Map from BitField to Dithered-Palette to Palette */
|
|
|
484 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical)
|
|
|
485 {
|
|
|
486 /* Generate a 256 color dither palette */
|
|
|
487 SDL_Palette dithered;
|
|
|
488 SDL_Color colors[256];
|
|
|
489
|
|
|
490 dithered.ncolors = 256;
|
|
|
491 SDL_DitherColors(colors, 8);
|
|
|
492 dithered.colors = colors;
|
|
|
493 return(Map1to1(&dithered, dst, identical));
|
|
|
494 }
|
|
|
495
|
|
|
496 SDL_BlitMap *SDL_AllocBlitMap(void)
|
|
|
497 {
|
|
|
498 SDL_BlitMap *map;
|
|
|
499
|
|
|
500 /* Allocate the empty map */
|
|
|
501 map = (SDL_BlitMap *)malloc(sizeof(*map));
|
|
|
502 if ( map == NULL ) {
|
|
|
503 SDL_OutOfMemory();
|
|
|
504 return(NULL);
|
|
|
505 }
|
|
|
506 memset(map, 0, sizeof(*map));
|
|
|
507
|
|
|
508 /* Allocate the software blit data */
|
|
|
509 map->sw_data = (struct private_swaccel *)malloc(sizeof(*map->sw_data));
|
|
|
510 if ( map->sw_data == NULL ) {
|
|
|
511 SDL_FreeBlitMap(map);
|
|
|
512 SDL_OutOfMemory();
|
|
|
513 return(NULL);
|
|
|
514 }
|
|
|
515 memset(map->sw_data, 0, sizeof(*map->sw_data));
|
|
|
516
|
|
|
517 /* It's ready to go */
|
|
|
518 return(map);
|
|
|
519 }
|
|
|
520 void SDL_InvalidateMap(SDL_BlitMap *map)
|
|
|
521 {
|
|
|
522 if ( ! map ) {
|
|
|
523 return;
|
|
|
524 }
|
|
|
525 map->dst = NULL;
|
|
|
526 map->format_version = (unsigned int)-1;
|
|
|
527 if ( map->table ) {
|
|
|
528 free(map->table);
|
|
|
529 map->table = NULL;
|
|
|
530 }
|
|
|
531 }
|
|
|
532 int SDL_MapSurface (SDL_Surface *src, SDL_Surface *dst)
|
|
|
533 {
|
|
|
534 SDL_PixelFormat *srcfmt;
|
|
|
535 SDL_PixelFormat *dstfmt;
|
|
|
536 SDL_BlitMap *map;
|
|
|
537
|
|
|
538 /* Clear out any previous mapping */
|
|
|
539 map = src->map;
|
|
|
540 if ( (src->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) {
|
|
|
541 SDL_UnRLESurface(src, 1);
|
|
|
542 }
|
|
|
543 SDL_InvalidateMap(map);
|
|
|
544
|
|
|
545 /* Figure out what kind of mapping we're doing */
|
|
|
546 map->identity = 0;
|
|
|
547 srcfmt = src->format;
|
|
|
548 dstfmt = dst->format;
|
|
|
549 switch (srcfmt->BytesPerPixel) {
|
|
|
550 case 1:
|
|
|
551 switch (dstfmt->BytesPerPixel) {
|
|
|
552 case 1:
|
|
|
553 /* Palette --> Palette */
|
|
|
554 /* If both SDL_HWSURFACE, assume have same palette */
|
|
|
555 if ( ((src->flags & SDL_HWSURFACE) == SDL_HWSURFACE) &&
|
|
|
556 ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) ) {
|
|
|
557 map->identity = 1;
|
|
|
558 } else {
|
|
|
559 map->table = Map1to1(srcfmt->palette,
|
|
|
560 dstfmt->palette, &map->identity);
|
|
|
561 }
|
|
|
562 if ( ! map->identity ) {
|
|
|
563 if ( map->table == NULL ) {
|
|
|
564 return(-1);
|
|
|
565 }
|
|
|
566 }
|
|
|
567 if (srcfmt->BitsPerPixel!=dstfmt->BitsPerPixel)
|
|
|
568 map->identity = 0;
|
|
|
569 break;
|
|
|
570
|
|
|
571 default:
|
|
|
572 /* Palette --> BitField */
|
|
|
573 map->table = Map1toN(srcfmt->palette, dstfmt);
|
|
|
574 if ( map->table == NULL ) {
|
|
|
575 return(-1);
|
|
|
576 }
|
|
|
577 break;
|
|
|
578 }
|
|
|
579 break;
|
|
|
580 default:
|
|
|
581 switch (dstfmt->BytesPerPixel) {
|
|
|
582 case 1:
|
|
|
583 /* BitField --> Palette */
|
|
|
584 map->table = MapNto1(srcfmt,
|
|
|
585 dstfmt->palette, &map->identity);
|
|
|
586 if ( ! map->identity ) {
|
|
|
587 if ( map->table == NULL ) {
|
|
|
588 return(-1);
|
|
|
589 }
|
|
|
590 }
|
|
|
591 map->identity = 0; /* Don't optimize to copy */
|
|
|
592 break;
|
|
|
593 default:
|
|
|
594 /* BitField --> BitField */
|
|
|
595 if ( FORMAT_EQUAL(srcfmt, dstfmt) )
|
|
|
596 map->identity = 1;
|
|
|
597 break;
|
|
|
598 }
|
|
|
599 break;
|
|
|
600 }
|
|
|
601
|
|
|
602 map->dst = dst;
|
|
|
603 map->format_version = dst->format_version;
|
|
|
604
|
|
|
605 /* Choose your blitters wisely */
|
|
|
606 return(SDL_CalculateBlit(src));
|
|
|
607 }
|
|
|
608 void SDL_FreeBlitMap(SDL_BlitMap *map)
|
|
|
609 {
|
|
|
610 if ( map ) {
|
|
|
611 SDL_InvalidateMap(map);
|
|
|
612 if ( map->sw_data != NULL ) {
|
|
|
613 free(map->sw_data);
|
|
|
614 }
|
|
|
615 free(map);
|
|
|
616 }
|
|
|
617 }
|
