This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
SDL_blit_1.c
1
2
/*
SDL - Simple DirectMedia Layer
3
Copyright (C) 1997-2006 Sam Lantinga
4
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Lesser General Public
7
License as published by the Free Software Foundation; either
8
version 2.1 of the License, or (at your option) any later version.
9
10
11
12
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
Lesser General Public License for more details.
15
16
17
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19
Sam Lantinga
20
slouken@libsdl.org
21
*/
22
#include "SDL_config.h"
23
24
25
26
27
28
29
30
#include "SDL_video.h"
#include "SDL_blit.h"
#include "SDL_sysvideo.h"
#include "SDL_endian.h"
/* Functions to blit from 8-bit surfaces to other surfaces */
31
32
static void
Blit1to1(SDL_BlitInfo * info)
33
34
{
#ifndef USE_DUFFS_LOOP
36
#endif
37
38
39
40
41
int width, height;
Uint8 *src, *map, *dst;
int srcskip, dstskip;
/* Set up some basic variables */
42
43
44
width = info->dst_w;
height = info->dst_h;
src = info->src;
45
srcskip = info->s_skip;
46
47
dst = info->dst;
dstskip = info->dst_pitch;
48
49
50
map = info->table;
while (height--) {
51
#ifdef USE_DUFFS_LOOP
52
/* *INDENT-OFF* */
53
54
55
56
57
58
59
DUFFS_LOOP(
{
*dst = map[*src];
}
dst++;
src++;
, width);
60
/* *INDENT-ON* */
61
#else
62
63
64
65
66
for (c = width; c; --c) {
*dst = map[*src];
dst++;
src++;
}
67
#endif
68
69
70
src += srcskip;
dst += dstskip;
}
73
74
75
76
77
78
79
80
/* This is now endian dependent */
#if ( SDL_BYTEORDER == SDL_LIL_ENDIAN )
#define HI 1
#define LO 0
#else /* ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) */
#define HI 0
#define LO 1
#endif
81
82
static void
Blit1to2(SDL_BlitInfo * info)
83
84
{
#ifndef USE_DUFFS_LOOP
86
#endif
87
88
89
90
91
92
int width, height;
Uint8 *src, *dst;
Uint16 *map;
int srcskip, dstskip;
/* Set up some basic variables */
93
94
95
width = info->dst_w;
height = info->dst_h;
src = info->src;
96
srcskip = info->s_skip;
97
98
dst = info->dst;
dstskip = info->dst_pitch;
99
map = (Uint16 *) info->table;
100
101
#ifdef USE_DUFFS_LOOP
102
103
while (height--) {
/* *INDENT-OFF* */
104
105
106
107
108
109
DUFFS_LOOP(
{
*(Uint16 *)dst = map[*src++];
dst += 2;
},
width);
110
111
112
113
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
114
#else
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
/* Memory align at 4-byte boundary, if necessary */
if ((long) dst & 0x03) {
/* Don't do anything if width is 0 */
if (width == 0) {
return;
}
--width;
while (height--) {
/* Perform copy alignment */
*(Uint16 *) dst = map[*src++];
dst += 2;
/* Copy in 4 pixel chunks */
for (c = width / 4; c; --c) {
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
}
/* Get any leftovers */
switch (width & 3) {
case 3:
*(Uint16 *) dst = map[*src++];
dst += 2;
case 2:
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
break;
case 1:
*(Uint16 *) dst = map[*src++];
dst += 2;
break;
}
src += srcskip;
dst += dstskip;
}
} else {
while (height--) {
/* Copy in 4 pixel chunks */
for (c = width / 4; c; --c) {
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
}
/* Get any leftovers */
switch (width & 3) {
case 3:
*(Uint16 *) dst = map[*src++];
dst += 2;
case 2:
*(Uint32 *) dst = (map[src[HI]] << 16) | (map[src[LO]]);
src += 2;
dst += 4;
break;
case 1:
*(Uint16 *) dst = map[*src++];
dst += 2;
break;
}
src += srcskip;
dst += dstskip;
}
}
185
186
#endif /* USE_DUFFS_LOOP */
}
187
188
static void
Blit1to3(SDL_BlitInfo * info)
189
190
{
#ifndef USE_DUFFS_LOOP
192
#endif
193
194
195
196
197
198
int o;
int width, height;
Uint8 *src, *map, *dst;
int srcskip, dstskip;
/* Set up some basic variables */
199
200
201
width = info->dst_w;
height = info->dst_h;
src = info->src;
202
srcskip = info->s_skip;
203
204
dst = info->dst;
dstskip = info->dst_pitch;
205
206
207
map = info->table;
while (height--) {
208
#ifdef USE_DUFFS_LOOP
209
/* *INDENT-OFF* */
210
211
212
213
214
215
216
217
218
219
DUFFS_LOOP(
{
o = *src * 4;
dst[0] = map[o++];
dst[1] = map[o++];
dst[2] = map[o++];
}
src++;
dst += 3;
, width);
220
/* *INDENT-ON* */
221
#else
222
223
224
225
226
227
228
229
for (c = width; c; --c) {
o = *src * 4;
dst[0] = map[o++];
dst[1] = map[o++];
dst[2] = map[o++];
src++;
dst += 3;
}
230
#endif /* USE_DUFFS_LOOP */
231
232
233
src += srcskip;
dst += dstskip;
}
234
}
235
236
static void
Blit1to4(SDL_BlitInfo * info)
237
238
{
#ifndef USE_DUFFS_LOOP
240
#endif
241
242
243
244
245
246
int width, height;
Uint8 *src;
Uint32 *map, *dst;
int srcskip, dstskip;
/* Set up some basic variables */
247
248
249
width = info->dst_w;
height = info->dst_h;
src = info->src;
250
srcskip = info->s_skip;
251
252
dst = (Uint32 *) info->dst;
dstskip = info->dst_pitch / 4;
253
254
255
map = (Uint32 *) info->table;
while (height--) {
256
#ifdef USE_DUFFS_LOOP
257
/* *INDENT-OFF* */
258
259
260
DUFFS_LOOP(
*dst++ = map[*src++];
, width);
261
/* *INDENT-ON* */
262
#else
263
264
265
266
267
268
269
270
271
272
273
274
275
276
for (c = width / 4; c; --c) {
*dst++ = map[*src++];
*dst++ = map[*src++];
*dst++ = map[*src++];
*dst++ = map[*src++];
}
switch (width & 3) {
case 3:
*dst++ = map[*src++];
case 2:
*dst++ = map[*src++];
case 1:
*dst++ = map[*src++];
}
277
#endif /* USE_DUFFS_LOOP */
278
279
280
src += srcskip;
dst += dstskip;
}
281
282
}
283
284
static void
Blit1to1Key(SDL_BlitInfo * info)
285
{
286
287
288
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
289
int srcskip = info->s_skip;
290
291
Uint8 *dst = info->dst;
int dstskip = info->dst_pitch;
292
Uint8 *palmap = info->table;
293
Uint32 ckey = info->ckey;
294
295
296
297
if (palmap) {
while (height--) {
/* *INDENT-OFF* */
298
299
300
301
302
303
304
305
306
DUFFS_LOOP(
{
if ( *src != ckey ) {
*dst = palmap[*src];
}
dst++;
src++;
},
width);
307
308
309
310
311
312
313
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
} else {
while (height--) {
/* *INDENT-OFF* */
314
315
316
317
318
319
320
321
322
DUFFS_LOOP(
{
if ( *src != ckey ) {
*dst = *src;
}
dst++;
src++;
},
width);
323
324
325
326
327
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
}
328
329
}
330
331
static void
Blit1to2Key(SDL_BlitInfo * info)
332
{
333
334
335
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
336
int srcskip = info->s_skip;
337
338
Uint16 *dstp = (Uint16 *) info->dst;
int dstskip = info->dst_pitch;
339
Uint16 *palmap = (Uint16 *) info->table;
340
Uint32 ckey = info->ckey;
341
342
343
344
345
346
/* Set up some basic variables */
dstskip /= 2;
while (height--) {
/* *INDENT-OFF* */
347
348
349
350
351
352
353
354
355
DUFFS_LOOP(
{
if ( *src != ckey ) {
*dstp=palmap[*src];
}
src++;
dstp++;
},
width);
356
357
358
359
/* *INDENT-ON* */
src += srcskip;
dstp += dstskip;
}
360
361
}
362
363
static void
Blit1to3Key(SDL_BlitInfo * info)
364
{
365
366
367
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
368
int srcskip = info->s_skip;
369
370
Uint8 *dst = info->dst;
int dstskip = info->dst_pitch;
371
Uint8 *palmap = info->table;
372
Uint32 ckey = info->ckey;
373
374
375
376
int o;
while (height--) {
/* *INDENT-OFF* */
377
378
379
380
381
382
383
384
385
386
387
388
DUFFS_LOOP(
{
if ( *src != ckey ) {
o = *src * 4;
dst[0] = palmap[o++];
dst[1] = palmap[o++];
dst[2] = palmap[o++];
}
src++;
dst += 3;
},
width);
389
390
391
392
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
393
394
}
395
396
static void
Blit1to4Key(SDL_BlitInfo * info)
397
{
398
399
400
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
401
int srcskip = info->s_skip;
402
403
Uint32 *dstp = (Uint32 *) info->dst;
int dstskip = info->dst_pitch;
404
Uint32 *palmap = (Uint32 *) info->table;
405
Uint32 ckey = info->ckey;
406
407
408
409
410
411
/* Set up some basic variables */
dstskip /= 4;
while (height--) {
/* *INDENT-OFF* */
412
413
414
415
416
417
418
419
420
DUFFS_LOOP(
{
if ( *src != ckey ) {
*dstp = palmap[*src];
}
src++;
dstp++;
},
width);
421
422
423
424
/* *INDENT-ON* */
src += srcskip;
dstp += dstskip;
}
425
426
}
427
428
static void
Blit1toNAlpha(SDL_BlitInfo * info)
429
{
430
431
432
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
433
int srcskip = info->s_skip;
434
435
Uint8 *dst = info->dst;
int dstskip = info->dst_pitch;
436
437
438
SDL_PixelFormat *dstfmt = info->dst;
const SDL_Color *srcpal = info->src->palette->colors;
int dstbpp;
439
const int A = (info->cmod >> 24);
440
441
442
443
444
445
446
447
/* Set up some basic variables */
dstbpp = dstfmt->BytesPerPixel;
while (height--) {
int sR, sG, sB;
int dR, dG, dB;
/* *INDENT-OFF* */
448
449
450
451
452
453
454
455
456
457
458
459
460
461
DUFFS_LOOP4(
{
Uint32 pixel;
sR = srcpal[*src].r;
sG = srcpal[*src].g;
sB = srcpal[*src].b;
DISEMBLE_RGB(dst, dstbpp, dstfmt,
pixel, dR, dG, dB);
ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
src++;
dst += dstbpp;
},
width);
462
463
464
465
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
466
467
}
468
469
static void
Blit1toNAlphaKey(SDL_BlitInfo * info)
470
{
471
472
473
int width = info->dst_w;
int height = info->dst_h;
Uint8 *src = info->src;
474
int srcskip = info->s_skip;
475
476
Uint8 *dst = info->dst;
int dstskip = info->dst_pitch;
477
478
479
SDL_PixelFormat *srcfmt = info->src;
SDL_PixelFormat *dstfmt = info->dst;
const SDL_Color *srcpal = info->src->palette->colors;
480
Uint32 ckey = info->ckey;
482
const int A = (info->cmod >> 24);
483
484
485
486
487
488
489
490
/* Set up some basic variables */
dstbpp = dstfmt->BytesPerPixel;
while (height--) {
int sR, sG, sB;
int dR, dG, dB;
/* *INDENT-OFF* */
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
DUFFS_LOOP(
{
if ( *src != ckey ) {
Uint32 pixel;
sR = srcpal[*src].r;
sG = srcpal[*src].g;
sB = srcpal[*src].b;
DISEMBLE_RGB(dst, dstbpp, dstfmt,
pixel, dR, dG, dB);
ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
}
src++;
dst += dstbpp;
},
width);
507
508
509
510
/* *INDENT-ON* */
src += srcskip;
dst += dstskip;
}
511
512
513
}
static SDL_loblit one_blit[] = {
514
NULL, Blit1to1, Blit1to2, Blit1to3, Blit1to4
515
516
517
};
static SDL_loblit one_blitkey[] = {
518
NULL, Blit1to1Key, Blit1to2Key, Blit1to3Key, Blit1to4Key
519
520
};
521
522
SDL_loblit
SDL_CalculateBlit1(SDL_Surface * surface, int blit_index)
523
{
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
int which;
SDL_PixelFormat *dstfmt;
dstfmt = surface->map->dst->format;
if (dstfmt->BitsPerPixel < 8) {
which = 0;
} else {
which = dstfmt->BytesPerPixel;
}
switch (blit_index) {
case 0: /* copy */
return one_blit[which];
case 1: /* colorkey */
return one_blitkey[which];
case 2: /* alpha */
/* Supporting 8bpp->8bpp alpha is doable but requires lots of
tables which consume space and takes time to precompute,
so is better left to the user */
return which >= 2 ? Blit1toNAlpha : NULL;
case 3: /* alpha + colorkey */
return which >= 2 ? Blit1toNAlphaKey : NULL;
}
return NULL;
551
}
552
553
/* vi: set ts=4 sw=4 expandtab: */