SDL 2.0
SDL_pixels.c
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20*/
21#include "../SDL_internal.h"
22
23/* General (mostly internal) pixel/color manipulation routines for SDL */
24
25#include "SDL_endian.h"
26#include "SDL_video.h"
27#include "SDL_sysvideo.h"
28#include "SDL_blit.h"
29#include "SDL_pixels_c.h"
30#include "SDL_RLEaccel_c.h"
31
32
33/* Lookup tables to expand partial bytes to the full 0..255 range */
34
35static Uint8 lookup_0[] = {
360, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255
37};
38
39static Uint8 lookup_1[] = {
400, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180, 182, 184, 186, 188, 190, 192, 194, 196, 198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 238, 240, 242, 244, 246, 248, 250, 252, 255
41};
42
43static Uint8 lookup_2[] = {
440, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 170, 174, 178, 182, 186, 190, 194, 198, 202, 206, 210, 214, 218, 222, 226, 230, 234, 238, 242, 246, 250, 255
45};
46
47static Uint8 lookup_3[] = {
480, 8, 16, 24, 32, 41, 49, 57, 65, 74, 82, 90, 98, 106, 115, 123, 131, 139, 148, 156, 164, 172, 180, 189, 197, 205, 213, 222, 230, 238, 246, 255
49};
50
51static Uint8 lookup_4[] = {
520, 17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204, 221, 238, 255
53};
54
55static Uint8 lookup_5[] = {
560, 36, 72, 109, 145, 182, 218, 255
57};
58
59static Uint8 lookup_6[] = {
600, 85, 170, 255
61};
62
63static Uint8 lookup_7[] = {
640, 255
65};
66
67static Uint8 lookup_8[] = {
68255
69};
70
81};
82
83/* Helper functions */
84
85const char*
87{
88 switch (format) {
89#define CASE(X) case X: return #X;
127#undef CASE
128 default:
129 return "SDL_PIXELFORMAT_UNKNOWN";
130 }
131}
132
135 Uint32 * Gmask, Uint32 * Bmask, Uint32 * Amask)
136{
137 Uint32 masks[4];
138
139 /* This function doesn't work with FourCC pixel formats */
141 SDL_SetError("FOURCC pixel formats are not supported");
142 return SDL_FALSE;
143 }
144
145 /* Initialize the values here */
146 if (SDL_BYTESPERPIXEL(format) <= 2) {
147 *bpp = SDL_BITSPERPIXEL(format);
148 } else {
149 *bpp = SDL_BYTESPERPIXEL(format) * 8;
150 }
151 *Rmask = *Gmask = *Bmask = *Amask = 0;
152
154#if SDL_BYTEORDER == SDL_BIG_ENDIAN
155 *Rmask = 0x00FF0000;
156 *Gmask = 0x0000FF00;
157 *Bmask = 0x000000FF;
158#else
159 *Rmask = 0x000000FF;
160 *Gmask = 0x0000FF00;
161 *Bmask = 0x00FF0000;
162#endif
163 return SDL_TRUE;
164 }
165
167#if SDL_BYTEORDER == SDL_BIG_ENDIAN
168 *Rmask = 0x000000FF;
169 *Gmask = 0x0000FF00;
170 *Bmask = 0x00FF0000;
171#else
172 *Rmask = 0x00FF0000;
173 *Gmask = 0x0000FF00;
174 *Bmask = 0x000000FF;
175#endif
176 return SDL_TRUE;
177 }
178
182 /* Not a format that uses masks */
183 return SDL_TRUE;
184 }
185
186 switch (SDL_PIXELLAYOUT(format)) {
188 masks[0] = 0x00000000;
189 masks[1] = 0x000000E0;
190 masks[2] = 0x0000001C;
191 masks[3] = 0x00000003;
192 break;
194 masks[0] = 0x0000F000;
195 masks[1] = 0x00000F00;
196 masks[2] = 0x000000F0;
197 masks[3] = 0x0000000F;
198 break;
200 masks[0] = 0x00008000;
201 masks[1] = 0x00007C00;
202 masks[2] = 0x000003E0;
203 masks[3] = 0x0000001F;
204 break;
206 masks[0] = 0x0000F800;
207 masks[1] = 0x000007C0;
208 masks[2] = 0x0000003E;
209 masks[3] = 0x00000001;
210 break;
212 masks[0] = 0x00000000;
213 masks[1] = 0x0000F800;
214 masks[2] = 0x000007E0;
215 masks[3] = 0x0000001F;
216 break;
218 masks[0] = 0xFF000000;
219 masks[1] = 0x00FF0000;
220 masks[2] = 0x0000FF00;
221 masks[3] = 0x000000FF;
222 break;
224 masks[0] = 0xC0000000;
225 masks[1] = 0x3FF00000;
226 masks[2] = 0x000FFC00;
227 masks[3] = 0x000003FF;
228 break;
230 masks[0] = 0xFFC00000;
231 masks[1] = 0x003FF000;
232 masks[2] = 0x00000FFC;
233 masks[3] = 0x00000003;
234 break;
235 default:
236 SDL_SetError("Unknown pixel format");
237 return SDL_FALSE;
238 }
239
240 switch (SDL_PIXELORDER(format)) {
242 *Rmask = masks[1];
243 *Gmask = masks[2];
244 *Bmask = masks[3];
245 break;
247 *Rmask = masks[0];
248 *Gmask = masks[1];
249 *Bmask = masks[2];
250 break;
252 *Amask = masks[0];
253 *Rmask = masks[1];
254 *Gmask = masks[2];
255 *Bmask = masks[3];
256 break;
258 *Rmask = masks[0];
259 *Gmask = masks[1];
260 *Bmask = masks[2];
261 *Amask = masks[3];
262 break;
264 *Bmask = masks[1];
265 *Gmask = masks[2];
266 *Rmask = masks[3];
267 break;
269 *Bmask = masks[0];
270 *Gmask = masks[1];
271 *Rmask = masks[2];
272 break;
274 *Bmask = masks[0];
275 *Gmask = masks[1];
276 *Rmask = masks[2];
277 *Amask = masks[3];
278 break;
280 *Amask = masks[0];
281 *Bmask = masks[1];
282 *Gmask = masks[2];
283 *Rmask = masks[3];
284 break;
285 default:
286 SDL_SetError("Unknown pixel format");
287 return SDL_FALSE;
288 }
289 return SDL_TRUE;
290}
291
292Uint32
293SDL_MasksToPixelFormatEnum(int bpp, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask,
294 Uint32 Amask)
295{
296 switch (bpp) {
297 case 1:
298 /* SDL defaults to MSB ordering */
300 case 4:
301 /* SDL defaults to MSB ordering */
303 case 8:
304 if (Rmask == 0) {
306 }
307 if (Rmask == 0xE0 &&
308 Gmask == 0x1C &&
309 Bmask == 0x03 &&
310 Amask == 0x00) {
312 }
313 break;
314 case 12:
315 if (Rmask == 0) {
317 }
318 if (Rmask == 0x0F00 &&
319 Gmask == 0x00F0 &&
320 Bmask == 0x000F &&
321 Amask == 0x0000) {
323 }
324 break;
325 case 15:
326 if (Rmask == 0) {
328 }
329 /* fallthrough */
330 case 16:
331 if (Rmask == 0) {
333 }
334 if (Rmask == 0x7C00 &&
335 Gmask == 0x03E0 &&
336 Bmask == 0x001F &&
337 Amask == 0x0000) {
339 }
340 if (Rmask == 0x001F &&
341 Gmask == 0x03E0 &&
342 Bmask == 0x7C00 &&
343 Amask == 0x0000) {
345 }
346 if (Rmask == 0x0F00 &&
347 Gmask == 0x00F0 &&
348 Bmask == 0x000F &&
349 Amask == 0xF000) {
351 }
352 if (Rmask == 0xF000 &&
353 Gmask == 0x0F00 &&
354 Bmask == 0x00F0 &&
355 Amask == 0x000F) {
357 }
358 if (Rmask == 0x000F &&
359 Gmask == 0x00F0 &&
360 Bmask == 0x0F00 &&
361 Amask == 0xF000) {
363 }
364 if (Rmask == 0x00F0 &&
365 Gmask == 0x0F00 &&
366 Bmask == 0xF000 &&
367 Amask == 0x000F) {
369 }
370 if (Rmask == 0x7C00 &&
371 Gmask == 0x03E0 &&
372 Bmask == 0x001F &&
373 Amask == 0x8000) {
375 }
376 if (Rmask == 0xF800 &&
377 Gmask == 0x07C0 &&
378 Bmask == 0x003E &&
379 Amask == 0x0001) {
381 }
382 if (Rmask == 0x001F &&
383 Gmask == 0x03E0 &&
384 Bmask == 0x7C00 &&
385 Amask == 0x8000) {
387 }
388 if (Rmask == 0x003E &&
389 Gmask == 0x07C0 &&
390 Bmask == 0xF800 &&
391 Amask == 0x0001) {
393 }
394 if (Rmask == 0xF800 &&
395 Gmask == 0x07E0 &&
396 Bmask == 0x001F &&
397 Amask == 0x0000) {
399 }
400 if (Rmask == 0x001F &&
401 Gmask == 0x07E0 &&
402 Bmask == 0xF800 &&
403 Amask == 0x0000) {
405 }
406 if (Rmask == 0x003F &&
407 Gmask == 0x07C0 &&
408 Bmask == 0xF800 &&
409 Amask == 0x0000) {
410 /* Technically this would be BGR556, but Witek says this works in bug 3158 */
412 }
413 break;
414 case 24:
415 switch (Rmask) {
416 case 0:
417 case 0x00FF0000:
418#if SDL_BYTEORDER == SDL_BIG_ENDIAN
420#else
422#endif
423 case 0x000000FF:
424#if SDL_BYTEORDER == SDL_BIG_ENDIAN
426#else
428#endif
429 }
430 case 32:
431 if (Rmask == 0) {
433 }
434 if (Rmask == 0x00FF0000 &&
435 Gmask == 0x0000FF00 &&
436 Bmask == 0x000000FF &&
437 Amask == 0x00000000) {
439 }
440 if (Rmask == 0xFF000000 &&
441 Gmask == 0x00FF0000 &&
442 Bmask == 0x0000FF00 &&
443 Amask == 0x00000000) {
445 }
446 if (Rmask == 0x000000FF &&
447 Gmask == 0x0000FF00 &&
448 Bmask == 0x00FF0000 &&
449 Amask == 0x00000000) {
451 }
452 if (Rmask == 0x0000FF00 &&
453 Gmask == 0x00FF0000 &&
454 Bmask == 0xFF000000 &&
455 Amask == 0x00000000) {
457 }
458 if (Rmask == 0x00FF0000 &&
459 Gmask == 0x0000FF00 &&
460 Bmask == 0x000000FF &&
461 Amask == 0xFF000000) {
463 }
464 if (Rmask == 0xFF000000 &&
465 Gmask == 0x00FF0000 &&
466 Bmask == 0x0000FF00 &&
467 Amask == 0x000000FF) {
469 }
470 if (Rmask == 0x000000FF &&
471 Gmask == 0x0000FF00 &&
472 Bmask == 0x00FF0000 &&
473 Amask == 0xFF000000) {
475 }
476 if (Rmask == 0x0000FF00 &&
477 Gmask == 0x00FF0000 &&
478 Bmask == 0xFF000000 &&
479 Amask == 0x000000FF) {
481 }
482 if (Rmask == 0x3FF00000 &&
483 Gmask == 0x000FFC00 &&
484 Bmask == 0x000003FF &&
485 Amask == 0xC0000000) {
487 }
488 }
490}
491
494
497{
499
501
502 /* Look it up in our list of previously allocated formats */
503 for (format = formats; format; format = format->next) {
504 if (pixel_format == format->format) {
505 ++format->refcount;
507 return format;
508 }
509 }
510
511 /* Allocate an empty pixel format structure, and initialize it */
512 format = SDL_malloc(sizeof(*format));
513 if (format == NULL) {
516 return NULL;
517 }
518 if (SDL_InitFormat(format, pixel_format) < 0) {
521 SDL_InvalidParamError("format");
522 return NULL;
523 }
524
525 if (!SDL_ISPIXELFORMAT_INDEXED(pixel_format)) {
526 /* Cache the RGB formats */
527 format->next = formats;
528 formats = format;
529 }
530
532
533 return format;
534}
535
536int
538{
539 int bpp;
540 Uint32 Rmask, Gmask, Bmask, Amask;
541 Uint32 mask;
542
543 if (!SDL_PixelFormatEnumToMasks(pixel_format, &bpp,
544 &Rmask, &Gmask, &Bmask, &Amask)) {
545 return -1;
546 }
547
548 /* Set up the format */
550 format->format = pixel_format;
551 format->BitsPerPixel = bpp;
552 format->BytesPerPixel = (bpp + 7) / 8;
553
554 format->Rmask = Rmask;
555 format->Rshift = 0;
556 format->Rloss = 8;
557 if (Rmask) {
558 for (mask = Rmask; !(mask & 0x01); mask >>= 1)
559 ++format->Rshift;
560 for (; (mask & 0x01); mask >>= 1)
561 --format->Rloss;
562 }
563
564 format->Gmask = Gmask;
565 format->Gshift = 0;
566 format->Gloss = 8;
567 if (Gmask) {
568 for (mask = Gmask; !(mask & 0x01); mask >>= 1)
569 ++format->Gshift;
570 for (; (mask & 0x01); mask >>= 1)
571 --format->Gloss;
572 }
573
574 format->Bmask = Bmask;
575 format->Bshift = 0;
576 format->Bloss = 8;
577 if (Bmask) {
578 for (mask = Bmask; !(mask & 0x01); mask >>= 1)
579 ++format->Bshift;
580 for (; (mask & 0x01); mask >>= 1)
581 --format->Bloss;
582 }
583
584 format->Amask = Amask;
585 format->Ashift = 0;
586 format->Aloss = 8;
587 if (Amask) {
588 for (mask = Amask; !(mask & 0x01); mask >>= 1)
589 ++format->Ashift;
590 for (; (mask & 0x01); mask >>= 1)
591 --format->Aloss;
592 }
593
594 format->palette = NULL;
595 format->refcount = 1;
596 format->next = NULL;
597
598 return 0;
599}
600
601void
603{
604 SDL_PixelFormat *prev;
605
606 if (!format) {
607 SDL_InvalidParamError("format");
608 return;
609 }
610
612
613 if (--format->refcount > 0) {
615 return;
616 }
617
618 /* Remove this format from our list */
619 if (format == formats) {
620 formats = format->next;
621 } else if (formats) {
622 for (prev = formats; prev->next; prev = prev->next) {
623 if (prev->next == format) {
624 prev->next = format->next;
625 break;
626 }
627 }
628 }
629
631
632 if (format->palette) {
633 SDL_FreePalette(format->palette);
634 }
636}
637
640{
641 SDL_Palette *palette;
642
643 /* Input validation */
644 if (ncolors < 1) {
645 SDL_InvalidParamError("ncolors");
646 return NULL;
647 }
648
649 palette = (SDL_Palette *) SDL_malloc(sizeof(*palette));
650 if (!palette) {
652 return NULL;
653 }
654 palette->colors =
655 (SDL_Color *) SDL_malloc(ncolors * sizeof(*palette->colors));
656 if (!palette->colors) {
657 SDL_free(palette);
658 return NULL;
659 }
660 palette->ncolors = ncolors;
661 palette->version = 1;
662 palette->refcount = 1;
663
664 SDL_memset(palette->colors, 0xFF, ncolors * sizeof(*palette->colors));
665
666 return palette;
667}
668
669int
671{
672 if (!format) {
673 return SDL_SetError("SDL_SetPixelFormatPalette() passed NULL format");
674 }
675
676 if (palette && palette->ncolors > (1 << format->BitsPerPixel)) {
677 return SDL_SetError("SDL_SetPixelFormatPalette() passed a palette that doesn't match the format");
678 }
679
680 if (format->palette == palette) {
681 return 0;
682 }
683
684 if (format->palette) {
685 SDL_FreePalette(format->palette);
686 }
687
688 format->palette = palette;
689
690 if (format->palette) {
691 ++format->palette->refcount;
692 }
693
694 return 0;
695}
696
697int
699 int firstcolor, int ncolors)
700{
701 int status = 0;
702
703 /* Verify the parameters */
704 if (!palette) {
705 return -1;
706 }
707 if (ncolors > (palette->ncolors - firstcolor)) {
708 ncolors = (palette->ncolors - firstcolor);
709 status = -1;
710 }
711
712 if (colors != (palette->colors + firstcolor)) {
713 SDL_memcpy(palette->colors + firstcolor, colors,
714 ncolors * sizeof(*colors));
715 }
716 ++palette->version;
717 if (!palette->version) {
718 palette->version = 1;
719 }
720
721 return status;
722}
723
724void
726{
727 if (!palette) {
728 SDL_InvalidParamError("palette");
729 return;
730 }
731 if (--palette->refcount > 0) {
732 return;
733 }
734 SDL_free(palette->colors);
735 SDL_free(palette);
736}
737
738/*
739 * Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors
740 */
741void
743{
744 int i;
745 if (bpp != 8)
746 return; /* only 8bpp supported right now */
747
748 for (i = 0; i < 256; i++) {
749 int r, g, b;
750 /* map each bit field to the full [0, 255] interval,
751 so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */
752 r = i & 0xe0;
753 r |= r >> 3 | r >> 6;
754 colors[i].r = r;
755 g = (i << 3) & 0xe0;
756 g |= g >> 3 | g >> 6;
757 colors[i].g = g;
758 b = i & 0x3;
759 b |= b << 2;
760 b |= b << 4;
761 colors[i].b = b;
763 }
764}
765
766/*
767 * Match an RGB value to a particular palette index
768 */
769Uint8
771{
772 /* Do colorspace distance matching */
773 unsigned int smallest;
774 unsigned int distance;
775 int rd, gd, bd, ad;
776 int i;
777 Uint8 pixel = 0;
778
779 smallest = ~0;
780 for (i = 0; i < pal->ncolors; ++i) {
781 rd = pal->colors[i].r - r;
782 gd = pal->colors[i].g - g;
783 bd = pal->colors[i].b - b;
784 ad = pal->colors[i].a - a;
785 distance = (rd * rd) + (gd * gd) + (bd * bd) + (ad * ad);
786 if (distance < smallest) {
787 pixel = i;
788 if (distance == 0) { /* Perfect match! */
789 break;
790 }
791 smallest = distance;
792 }
793 }
794 return (pixel);
795}
796
797/* Find the opaque pixel value corresponding to an RGB triple */
798Uint32
800{
801 if (format->palette == NULL) {
802 return (r >> format->Rloss) << format->Rshift
803 | (g >> format->Gloss) << format->Gshift
804 | (b >> format->Bloss) << format->Bshift | format->Amask;
805 } else {
806 return SDL_FindColor(format->palette, r, g, b, SDL_ALPHA_OPAQUE);
807 }
808}
809
810/* Find the pixel value corresponding to an RGBA quadruple */
811Uint32
813 Uint8 a)
814{
815 if (format->palette == NULL) {
816 return (r >> format->Rloss) << format->Rshift
817 | (g >> format->Gloss) << format->Gshift
818 | (b >> format->Bloss) << format->Bshift
819 | ((a >> format->Aloss) << format->Ashift & format->Amask);
820 } else {
821 return SDL_FindColor(format->palette, r, g, b, a);
822 }
823}
824
825void
827 Uint8 * b)
828{
829 if (format->palette == NULL) {
830 unsigned v;
831 v = (pixel & format->Rmask) >> format->Rshift;
832 *r = SDL_expand_byte[format->Rloss][v];
833 v = (pixel & format->Gmask) >> format->Gshift;
834 *g = SDL_expand_byte[format->Gloss][v];
835 v = (pixel & format->Bmask) >> format->Bshift;
836 *b = SDL_expand_byte[format->Bloss][v];
837 } else {
838 if (pixel < (unsigned)format->palette->ncolors) {
839 *r = format->palette->colors[pixel].r;
840 *g = format->palette->colors[pixel].g;
841 *b = format->palette->colors[pixel].b;
842 } else {
843 *r = *g = *b = 0;
844 }
845 }
846}
847
848void
850 Uint8 * r, Uint8 * g, Uint8 * b, Uint8 * a)
851{
852 if (format->palette == NULL) {
853 unsigned v;
854 v = (pixel & format->Rmask) >> format->Rshift;
855 *r = SDL_expand_byte[format->Rloss][v];
856 v = (pixel & format->Gmask) >> format->Gshift;
857 *g = SDL_expand_byte[format->Gloss][v];
858 v = (pixel & format->Bmask) >> format->Bshift;
859 *b = SDL_expand_byte[format->Bloss][v];
860 v = (pixel & format->Amask) >> format->Ashift;
861 *a = SDL_expand_byte[format->Aloss][v];
862 } else {
863 if (pixel < (unsigned)format->palette->ncolors) {
864 *r = format->palette->colors[pixel].r;
865 *g = format->palette->colors[pixel].g;
866 *b = format->palette->colors[pixel].b;
867 *a = format->palette->colors[pixel].a;
868 } else {
869 *r = *g = *b = *a = 0;
870 }
871 }
872}
873
874/* Map from Palette to Palette */
875static Uint8 *
876Map1to1(SDL_Palette * src, SDL_Palette * dst, int *identical)
877{
878 Uint8 *map;
879 int i;
880
881 if (identical) {
882 if (src->ncolors <= dst->ncolors) {
883 /* If an identical palette, no need to map */
884 if (src == dst
885 ||
887 (src->colors, dst->colors,
888 src->ncolors * sizeof(SDL_Color)) == 0)) {
889 *identical = 1;
890 return (NULL);
891 }
892 }
893 *identical = 0;
894 }
895 map = (Uint8 *) SDL_malloc(src->ncolors);
896 if (map == NULL) {
898 return (NULL);
899 }
900 for (i = 0; i < src->ncolors; ++i) {
902 src->colors[i].r, src->colors[i].g,
903 src->colors[i].b, src->colors[i].a);
904 }
905 return (map);
906}
907
908/* Map from Palette to BitField */
909static Uint8 *
910Map1toN(SDL_PixelFormat * src, Uint8 Rmod, Uint8 Gmod, Uint8 Bmod, Uint8 Amod,
912{
913 Uint8 *map;
914 int i;
915 int bpp;
916 SDL_Palette *pal = src->palette;
917
918 bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel);
919 map = (Uint8 *) SDL_malloc(pal->ncolors * bpp);
920 if (map == NULL) {
922 return (NULL);
923 }
924
925 /* We memory copy to the pixel map so the endianness is preserved */
926 for (i = 0; i < pal->ncolors; ++i) {
927 Uint8 R = (Uint8) ((pal->colors[i].r * Rmod) / 255);
928 Uint8 G = (Uint8) ((pal->colors[i].g * Gmod) / 255);
929 Uint8 B = (Uint8) ((pal->colors[i].b * Bmod) / 255);
930 Uint8 A = (Uint8) ((pal->colors[i].a * Amod) / 255);
931 ASSEMBLE_RGBA(&map[i * bpp], dst->BytesPerPixel, dst, R, G, B, A);
932 }
933 return (map);
934}
935
936/* Map from BitField to Dithered-Palette to Palette */
937static Uint8 *
939{
940 /* Generate a 256 color dither palette */
941 SDL_Palette dithered;
942 SDL_Color colors[256];
943 SDL_Palette *pal = dst->palette;
944
945 dithered.ncolors = 256;
947 dithered.colors = colors;
948 return (Map1to1(&dithered, pal, identical));
949}
950
953{
955
956 /* Allocate the empty map */
957 map = (SDL_BlitMap *) SDL_calloc(1, sizeof(*map));
958 if (map == NULL) {
960 return (NULL);
961 }
962 map->info.r = 0xFF;
963 map->info.g = 0xFF;
964 map->info.b = 0xFF;
965 map->info.a = 0xFF;
966
967 /* It's ready to go */
968 return (map);
969}
970
971void
973{
974 if (!map) {
975 return;
976 }
977 if (map->dst) {
978 /* Release our reference to the surface - see the note below */
979 if (--map->dst->refcount <= 0) {
980 SDL_FreeSurface(map->dst);
981 }
982 }
983 map->dst = NULL;
984 map->src_palette_version = 0;
985 map->dst_palette_version = 0;
986 SDL_free(map->info.table);
987 map->info.table = NULL;
988}
989
990int
992{
993 SDL_PixelFormat *srcfmt;
994 SDL_PixelFormat *dstfmt;
996
997 /* Clear out any previous mapping */
998 map = src->map;
999 if ((src->flags & SDL_RLEACCEL) == SDL_RLEACCEL) {
1001 }
1003
1004 /* Figure out what kind of mapping we're doing */
1005 map->identity = 0;
1006 srcfmt = src->format;
1007 dstfmt = dst->format;
1008 if (SDL_ISPIXELFORMAT_INDEXED(srcfmt->format)) {
1009 if (SDL_ISPIXELFORMAT_INDEXED(dstfmt->format)) {
1010 /* Palette --> Palette */
1011 map->info.table =
1012 Map1to1(srcfmt->palette, dstfmt->palette, &map->identity);
1013 if (!map->identity) {
1014 if (map->info.table == NULL) {
1015 return (-1);
1016 }
1017 }
1018 if (srcfmt->BitsPerPixel != dstfmt->BitsPerPixel)
1019 map->identity = 0;
1020 } else {
1021 /* Palette --> BitField */
1022 map->info.table =
1023 Map1toN(srcfmt, src->map->info.r, src->map->info.g,
1024 src->map->info.b, src->map->info.a, dstfmt);
1025 if (map->info.table == NULL) {
1026 return (-1);
1027 }
1028 }
1029 } else {
1030 if (SDL_ISPIXELFORMAT_INDEXED(dstfmt->format)) {
1031 /* BitField --> Palette */
1032 map->info.table = MapNto1(srcfmt, dstfmt, &map->identity);
1033 if (!map->identity) {
1034 if (map->info.table == NULL) {
1035 return (-1);
1036 }
1037 }
1038 map->identity = 0; /* Don't optimize to copy */
1039 } else {
1040 /* BitField --> BitField */
1041 if (srcfmt == dstfmt) {
1042 map->identity = 1;
1043 }
1044 }
1045 }
1046
1047 map->dst = dst;
1048
1049 if (map->dst) {
1050 /* Keep a reference to this surface so it doesn't get deleted
1051 while we're still pointing at it.
1052
1053 A better method would be for the destination surface to keep
1054 track of surfaces that are mapped to it and automatically
1055 invalidate them when it is freed, but this will do for now.
1056 */
1057 ++map->dst->refcount;
1058 }
1059
1060 if (dstfmt->palette) {
1061 map->dst_palette_version = dstfmt->palette->version;
1062 } else {
1063 map->dst_palette_version = 0;
1064 }
1065
1066 if (srcfmt->palette) {
1067 map->src_palette_version = srcfmt->palette->version;
1068 } else {
1069 map->src_palette_version = 0;
1070 }
1071
1072 /* Choose your blitters wisely */
1073 return (SDL_CalculateBlit(src));
1074}
1075
1076void
1078{
1079 if (map) {
1081 SDL_free(map);
1082 }
1083}
1084
1085void
1086SDL_CalculateGammaRamp(float gamma, Uint16 * ramp)
1087{
1088 int i;
1089
1090 /* Input validation */
1091 if (gamma < 0.0f ) {
1092 SDL_InvalidParamError("gamma");
1093 return;
1094 }
1095 if (ramp == NULL) {
1096 SDL_InvalidParamError("ramp");
1097 return;
1098 }
1099
1100 /* 0.0 gamma is all black */
1101 if (gamma == 0.0f) {
1102 SDL_memset(ramp, 0, 256 * sizeof(Uint16));
1103 return;
1104 } else if (gamma == 1.0f) {
1105 /* 1.0 gamma is identity */
1106 for (i = 0; i < 256; ++i) {
1107 ramp[i] = (i << 8) | i;
1108 }
1109 return;
1110 } else {
1111 /* Calculate a real gamma ramp */
1112 int value;
1113 gamma = 1.0f / gamma;
1114 for (i = 0; i < 256; ++i) {
1115 value =
1116 (int) (SDL_pow((double) i / 256.0, gamma) * 65535.0 + 0.5);
1117 if (value > 65535) {
1118 value = 65535;
1119 }
1120 ramp[i] = (Uint16) value;
1121 }
1122 }
1123}
1124
1125/* vi: set ts=4 sw=4 expandtab: */
void SDL_UnRLESurface(SDL_Surface *surface, int recode)
int SDL_SpinLock
Definition: SDL_atomic.h:89
int SDL_CalculateBlit(SDL_Surface *surface)
Definition: SDL_blit.c:216
#define ASSEMBLE_RGBA(buf, bpp, fmt, r, g, b, a)
Definition: SDL_blit.h:402
#define SDL_SetError
#define SDL_memset
#define SDL_AtomicLock
#define SDL_malloc
#define SDL_AtomicUnlock
#define SDL_free
#define SDL_memcmp
#define SDL_pow
#define SDL_memcpy
#define SDL_FreeSurface
#define SDL_calloc
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
#define SDL_InvalidParamError(param)
Definition: SDL_error.h:54
const GLubyte GLuint GLuint GLuint GLuint alpha GLboolean GLboolean GLboolean GLboolean alpha GLint GLint GLsizei GLsizei GLenum type GLenum GLint GLenum GLint GLint GLsizei GLsizei GLint border GLenum GLint GLint GLint GLint GLint GLsizei GLsizei height GLsizei GLsizei GLenum GLenum const GLvoid *pixels GLenum GLint GLint GLint GLint j2 GLdouble GLdouble GLdouble GLdouble GLdouble GLdouble zFar GLenum GLenum GLint *params GLenum GLenum GLint *params GLenum GLenum GLint *params GLenum GLenum GLfloat *params GLenum GLint GLenum GLenum GLvoid *pixels GLenum GLint GLenum GLint *params GLenum GLenum GLint *params GLenum GLsizei const GLvoid *pointer GLenum GLenum const GLint *params GLenum GLfloat GLfloat GLint GLint const GLfloat *points GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat *points GLint GLfloat GLfloat GLint GLfloat GLfloat v2 GLenum GLenum const GLint *params GLdouble GLdouble GLdouble GLdouble GLdouble GLdouble zFar GLenum map
Definition: SDL_glfuncs.h:291
const GLdouble * v
Definition: SDL_opengl.h:2064
GLdouble GLdouble GLdouble r
Definition: SDL_opengl.h:2079
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
GLboolean GLboolean GLboolean b
GLenum src
GLboolean GLboolean GLboolean GLboolean a
GLsizei GLsizei GLfloat distance
GLenum GLenum dst
GLboolean GLboolean g
GLsizei const GLfloat * value
GLenum GLint GLuint mask
int SDL_SetPaletteColors(SDL_Palette *palette, const SDL_Color *colors, int firstcolor, int ncolors)
Set a range of colors in a palette.
Definition: SDL_pixels.c:698
static SDL_PixelFormat * formats
Definition: SDL_pixels.c:492
static Uint8 lookup_8[]
Definition: SDL_pixels.c:67
void SDL_DitherColors(SDL_Color *colors, int bpp)
Definition: SDL_pixels.c:742
int SDL_SetPixelFormatPalette(SDL_PixelFormat *format, SDL_Palette *palette)
Set the palette for a pixel format structure.
Definition: SDL_pixels.c:670
static SDL_SpinLock formats_lock
Definition: SDL_pixels.c:493
void SDL_CalculateGammaRamp(float gamma, Uint16 *ramp)
Calculate a 256 entry gamma ramp for a gamma value.
Definition: SDL_pixels.c:1086
static Uint8 lookup_1[]
Definition: SDL_pixels.c:39
void SDL_FreeFormat(SDL_PixelFormat *format)
Free an SDL_PixelFormat structure.
Definition: SDL_pixels.c:602
SDL_bool SDL_PixelFormatEnumToMasks(Uint32 format, int *bpp, Uint32 *Rmask, Uint32 *Gmask, Uint32 *Bmask, Uint32 *Amask)
Convert one of the enumerated pixel formats to a bpp and RGBA masks.
Definition: SDL_pixels.c:134
SDL_PixelFormat * SDL_AllocFormat(Uint32 pixel_format)
Create an SDL_PixelFormat structure from a pixel format enum.
Definition: SDL_pixels.c:496
static Uint8 * MapNto1(SDL_PixelFormat *src, SDL_PixelFormat *dst, int *identical)
Definition: SDL_pixels.c:938
const char * SDL_GetPixelFormatName(Uint32 format)
Get the human readable name of a pixel format.
Definition: SDL_pixels.c:86
int SDL_InitFormat(SDL_PixelFormat *format, Uint32 pixel_format)
Definition: SDL_pixels.c:537
static Uint8 lookup_4[]
Definition: SDL_pixels.c:51
Uint32 SDL_MapRGBA(const SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
Maps an RGBA quadruple to a pixel value for a given pixel format.
Definition: SDL_pixels.c:812
Uint32 SDL_MasksToPixelFormatEnum(int bpp, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
Convert a bpp and RGBA masks to an enumerated pixel format.
Definition: SDL_pixels.c:293
static Uint8 * Map1toN(SDL_PixelFormat *src, Uint8 Rmod, Uint8 Gmod, Uint8 Bmod, Uint8 Amod, SDL_PixelFormat *dst)
Definition: SDL_pixels.c:910
Uint32 SDL_MapRGB(const SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b)
Maps an RGB triple to an opaque pixel value for a given pixel format.
Definition: SDL_pixels.c:799
void SDL_FreeBlitMap(SDL_BlitMap *map)
Definition: SDL_pixels.c:1077
void SDL_InvalidateMap(SDL_BlitMap *map)
Definition: SDL_pixels.c:972
#define CASE(X)
SDL_BlitMap * SDL_AllocBlitMap(void)
Definition: SDL_pixels.c:952
Uint8 * SDL_expand_byte[9]
Definition: SDL_pixels.c:71
SDL_Palette * SDL_AllocPalette(int ncolors)
Create a palette structure with the specified number of color entries.
Definition: SDL_pixels.c:639
void SDL_GetRGBA(Uint32 pixel, const SDL_PixelFormat *format, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
Get the RGBA components from a pixel of the specified format.
Definition: SDL_pixels.c:849
static Uint8 lookup_0[]
Definition: SDL_pixels.c:35
int SDL_MapSurface(SDL_Surface *src, SDL_Surface *dst)
Definition: SDL_pixels.c:991
void SDL_GetRGB(Uint32 pixel, const SDL_PixelFormat *format, Uint8 *r, Uint8 *g, Uint8 *b)
Get the RGB components from a pixel of the specified format.
Definition: SDL_pixels.c:826
static Uint8 lookup_3[]
Definition: SDL_pixels.c:47
static Uint8 * Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical)
Definition: SDL_pixels.c:876
void SDL_FreePalette(SDL_Palette *palette)
Free a palette created with SDL_AllocPalette().
Definition: SDL_pixels.c:725
static Uint8 lookup_5[]
Definition: SDL_pixels.c:55
static Uint8 lookup_6[]
Definition: SDL_pixels.c:59
static Uint8 lookup_2[]
Definition: SDL_pixels.c:43
static Uint8 lookup_7[]
Definition: SDL_pixels.c:63
Uint8 SDL_FindColor(SDL_Palette *pal, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
Definition: SDL_pixels.c:770
#define SDL_BYTESPERPIXEL(X)
Definition: SDL_pixels.h:128
#define SDL_PIXELORDER(X)
Definition: SDL_pixels.h:125
#define SDL_BITSPERPIXEL(X)
Definition: SDL_pixels.h:127
#define SDL_ALPHA_OPAQUE
Definition: SDL_pixels.h:46
@ SDL_PACKEDORDER_RGBX
Definition: SDL_pixels.h:80
@ SDL_PACKEDORDER_BGRX
Definition: SDL_pixels.h:84
@ SDL_PACKEDORDER_XBGR
Definition: SDL_pixels.h:83
@ SDL_PACKEDORDER_RGBA
Definition: SDL_pixels.h:82
@ SDL_PACKEDORDER_ABGR
Definition: SDL_pixels.h:85
@ SDL_PACKEDORDER_BGRA
Definition: SDL_pixels.h:86
@ SDL_PACKEDORDER_XRGB
Definition: SDL_pixels.h:79
@ SDL_PACKEDORDER_ARGB
Definition: SDL_pixels.h:81
#define SDL_PIXELLAYOUT(X)
Definition: SDL_pixels.h:126
#define SDL_ISPIXELFORMAT_INDEXED(format)
Definition: SDL_pixels.h:134
@ SDL_PIXELFORMAT_BGR565
Definition: SDL_pixels.h:227
@ SDL_PIXELFORMAT_YVYU
Definition: SDL_pixels.h:285
@ SDL_PIXELFORMAT_RGB332
Definition: SDL_pixels.h:188
@ SDL_PIXELFORMAT_INDEX1LSB
Definition: SDL_pixels.h:174
@ SDL_PIXELFORMAT_ABGR4444
Definition: SDL_pixels.h:206
@ SDL_PIXELFORMAT_BGRA4444
Definition: SDL_pixels.h:209
@ SDL_PIXELFORMAT_BGR24
Definition: SDL_pixels.h:233
@ SDL_PIXELFORMAT_INDEX4MSB
Definition: SDL_pixels.h:183
@ SDL_PIXELFORMAT_RGB555
Definition: SDL_pixels.h:194
@ SDL_PIXELFORMAT_RGB444
Definition: SDL_pixels.h:191
@ SDL_PIXELFORMAT_RGBA8888
Definition: SDL_pixels.h:251
@ SDL_PIXELFORMAT_RGBA5551
Definition: SDL_pixels.h:215
@ SDL_PIXELFORMAT_ARGB1555
Definition: SDL_pixels.h:212
@ SDL_PIXELFORMAT_INDEX8
Definition: SDL_pixels.h:186
@ SDL_PIXELFORMAT_UYVY
Definition: SDL_pixels.h:283
@ SDL_PIXELFORMAT_BGR888
Definition: SDL_pixels.h:242
@ SDL_PIXELFORMAT_YV12
Definition: SDL_pixels.h:277
@ SDL_PIXELFORMAT_BGRX8888
Definition: SDL_pixels.h:245
@ SDL_PIXELFORMAT_RGB24
Definition: SDL_pixels.h:230
@ SDL_PIXELFORMAT_RGB888
Definition: SDL_pixels.h:236
@ SDL_PIXELFORMAT_ABGR8888
Definition: SDL_pixels.h:254
@ SDL_PIXELFORMAT_YUY2
Definition: SDL_pixels.h:281
@ SDL_PIXELFORMAT_NV12
Definition: SDL_pixels.h:287
@ SDL_PIXELFORMAT_BGRA8888
Definition: SDL_pixels.h:257
@ SDL_PIXELFORMAT_ABGR1555
Definition: SDL_pixels.h:218
@ SDL_PIXELFORMAT_NV21
Definition: SDL_pixels.h:289
@ SDL_PIXELFORMAT_IYUV
Definition: SDL_pixels.h:279
@ SDL_PIXELFORMAT_ARGB8888
Definition: SDL_pixels.h:248
@ SDL_PIXELFORMAT_ARGB4444
Definition: SDL_pixels.h:200
@ SDL_PIXELFORMAT_INDEX1MSB
Definition: SDL_pixels.h:177
@ SDL_PIXELFORMAT_INDEX4LSB
Definition: SDL_pixels.h:180
@ SDL_PIXELFORMAT_RGBX8888
Definition: SDL_pixels.h:239
@ SDL_PIXELFORMAT_BGRA5551
Definition: SDL_pixels.h:221
@ SDL_PIXELFORMAT_RGB565
Definition: SDL_pixels.h:224
@ SDL_PIXELFORMAT_ARGB2101010
Definition: SDL_pixels.h:260
@ SDL_PIXELFORMAT_BGR555
Definition: SDL_pixels.h:197
@ SDL_PIXELFORMAT_UNKNOWN
Definition: SDL_pixels.h:173
@ SDL_PIXELFORMAT_RGBA4444
Definition: SDL_pixels.h:203
#define SDL_PIXELTYPE(X)
Definition: SDL_pixels.h:124
@ SDL_PACKEDLAYOUT_8888
Definition: SDL_pixels.h:112
@ SDL_PACKEDLAYOUT_1010102
Definition: SDL_pixels.h:114
@ SDL_PACKEDLAYOUT_565
Definition: SDL_pixels.h:111
@ SDL_PACKEDLAYOUT_332
Definition: SDL_pixels.h:107
@ SDL_PACKEDLAYOUT_5551
Definition: SDL_pixels.h:110
@ SDL_PACKEDLAYOUT_1555
Definition: SDL_pixels.h:109
@ SDL_PACKEDLAYOUT_4444
Definition: SDL_pixels.h:108
@ SDL_PACKEDLAYOUT_2101010
Definition: SDL_pixels.h:113
#define SDL_ISPIXELFORMAT_FOURCC(format)
Definition: SDL_pixels.h:167
@ SDL_PIXELTYPE_PACKED32
Definition: SDL_pixels.h:59
@ SDL_PIXELTYPE_PACKED8
Definition: SDL_pixels.h:57
@ SDL_PIXELTYPE_PACKED16
Definition: SDL_pixels.h:58
SDL_bool
Definition: SDL_stdinc.h:162
@ SDL_TRUE
Definition: SDL_stdinc.h:164
@ SDL_FALSE
Definition: SDL_stdinc.h:163
uint32_t Uint32
Definition: SDL_stdinc.h:203
#define SDL_zerop(x)
Definition: SDL_stdinc.h:417
uint16_t Uint16
Definition: SDL_stdinc.h:191
uint8_t Uint8
Definition: SDL_stdinc.h:179
#define SDL_RLEACCEL
Definition: SDL_surface.h:54
#define G(x, y, z)
Definition: SDL_test_md5.c:74
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
#define NULL
Definition: begin_code.h:167
EGLint EGLint * formats
Definition: eglext.h:718
Uint8 r
Definition: SDL_pixels.h:297
Uint8 b
Definition: SDL_pixels.h:299
Uint8 a
Definition: SDL_pixels.h:300
Uint8 g
Definition: SDL_pixels.h:298
Uint32 version
Definition: SDL_pixels.h:308
SDL_Color * colors
Definition: SDL_pixels.h:307
struct SDL_PixelFormat * next
Definition: SDL_pixels.h:335
Uint8 BitsPerPixel
Definition: SDL_pixels.h:319
SDL_Palette * palette
Definition: SDL_pixels.h:318
A collection of pixels used in software blitting.
Definition: SDL_surface.h:71
static int colors[7]
Definition: testgesture.c:41