| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 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 | 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 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | 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 | #include "SDL_video.h" |
| 25 | #include "SDL_blit.h" |
| 26 | #include "SDL_sysvideo.h" |
| 27 | #include "SDL_endian.h" |
| 28 | |
| 29 | /* Functions to blit from 8-bit surfaces to other surfaces */ |
| 30 | |
| 31 | static void Blit1to1(SDL_BlitInfo *info) |
| 32 | { |
| 33 | #ifndef USE_DUFFS_LOOP |
| 34 | int c; |
| 35 | #endif |
| 36 | int width, height; |
| 37 | Uint8 *src, *map, *dst; |
| 38 | int srcskip, dstskip; |
| 39 | |
| 40 | /* Set up some basic variables */ |
| 41 | width = info->d_width; |
| 42 | height = info->d_height; |
| 43 | src = info->s_pixels; |
| 44 | srcskip = info->s_skip; |
| 45 | dst = info->d_pixels; |
| 46 | dstskip = info->d_skip; |
| 47 | map = info->table; |
| 48 | |
| 49 | while ( height-- ) { |
| 50 | #ifdef USE_DUFFS_LOOP |
| 51 | DUFFS_LOOP( |
| 52 | { |
| 53 | *dst = map[*src]; |
| 54 | } |
| 55 | dst++; |
| 56 | src++; |
| 57 | , width); |
| 58 | #else |
| 59 | for ( c=width; c; --c ) { |
| 60 | *dst = map[*src]; |
| 61 | dst++; |
| 62 | src++; |
| 63 | } |
| 64 | #endif |
| 65 | src += srcskip; |
| 66 | dst += dstskip; |
| 67 | } |
| 68 | } |
| 69 | /* This is now endian dependent */ |
| 70 | #if ( SDL_BYTEORDER == SDL_LIL_ENDIAN ) |
| 71 | #define HI 1 |
| 72 | #define LO 0 |
| 73 | #else /* ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) */ |
| 74 | #define HI 0 |
| 75 | #define LO 1 |
| 76 | #endif |
| 77 | static void Blit1to2(SDL_BlitInfo *info) |
| 78 | { |
| 79 | #ifndef USE_DUFFS_LOOP |
| 80 | int c; |
| 81 | #endif |
| 82 | int width, height; |
| 83 | Uint8 *src, *dst; |
| 84 | Uint16 *map; |
| 85 | int srcskip, dstskip; |
| 86 | |
| 87 | /* Set up some basic variables */ |
| 88 | width = info->d_width; |
| 89 | height = info->d_height; |
| 90 | src = info->s_pixels; |
| 91 | srcskip = info->s_skip; |
| 92 | dst = info->d_pixels; |
| 93 | dstskip = info->d_skip; |
| 94 | map = (Uint16 *)info->table; |
| 95 | |
| 96 | #ifdef USE_DUFFS_LOOP |
| 97 | while ( height-- ) { |
| 98 | DUFFS_LOOP( |
| 99 | { |
| 100 | *(Uint16 *)dst = map[*src++]; |
| 101 | dst += 2; |
| 102 | }, |
| 103 | width); |
| 104 | src += srcskip; |
| 105 | dst += dstskip; |
| 106 | } |
| 107 | #else |
| 108 | /* Memory align at 4-byte boundary, if necessary */ |
| 109 | if ( (long)dst & 0x03 ) { |
| 110 | /* Don't do anything if width is 0 */ |
| 111 | if ( width == 0 ) { |
| 112 | return; |
| 113 | } |
| 114 | --width; |
| 115 | |
| 116 | while ( height-- ) { |
| 117 | /* Perform copy alignment */ |
| 118 | *(Uint16 *)dst = map[*src++]; |
| 119 | dst += 2; |
| 120 | |
| 121 | /* Copy in 4 pixel chunks */ |
| 122 | for ( c=width/4; c; --c ) { |
| 123 | *(Uint32 *)dst = |
| 124 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 125 | src += 2; |
| 126 | dst += 4; |
| 127 | *(Uint32 *)dst = |
| 128 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 129 | src += 2; |
| 130 | dst += 4; |
| 131 | } |
| 132 | /* Get any leftovers */ |
| 133 | switch (width & 3) { |
| 134 | case 3: |
| 135 | *(Uint16 *)dst = map[*src++]; |
| 136 | dst += 2; |
| 137 | case 2: |
| 138 | *(Uint32 *)dst = |
| 139 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 140 | src += 2; |
| 141 | dst += 4; |
| 142 | break; |
| 143 | case 1: |
| 144 | *(Uint16 *)dst = map[*src++]; |
| 145 | dst += 2; |
| 146 | break; |
| 147 | } |
| 148 | src += srcskip; |
| 149 | dst += dstskip; |
| 150 | } |
| 151 | } else { |
| 152 | while ( height-- ) { |
| 153 | /* Copy in 4 pixel chunks */ |
| 154 | for ( c=width/4; c; --c ) { |
| 155 | *(Uint32 *)dst = |
| 156 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 157 | src += 2; |
| 158 | dst += 4; |
| 159 | *(Uint32 *)dst = |
| 160 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 161 | src += 2; |
| 162 | dst += 4; |
| 163 | } |
| 164 | /* Get any leftovers */ |
| 165 | switch (width & 3) { |
| 166 | case 3: |
| 167 | *(Uint16 *)dst = map[*src++]; |
| 168 | dst += 2; |
| 169 | case 2: |
| 170 | *(Uint32 *)dst = |
| 171 | (map[src[HI]]<<16)|(map[src[LO]]); |
| 172 | src += 2; |
| 173 | dst += 4; |
| 174 | break; |
| 175 | case 1: |
| 176 | *(Uint16 *)dst = map[*src++]; |
| 177 | dst += 2; |
| 178 | break; |
| 179 | } |
| 180 | src += srcskip; |
| 181 | dst += dstskip; |
| 182 | } |
| 183 | } |
| 184 | #endif /* USE_DUFFS_LOOP */ |
| 185 | } |
| 186 | static void Blit1to3(SDL_BlitInfo *info) |
| 187 | { |
| 188 | #ifndef USE_DUFFS_LOOP |
| 189 | int c; |
| 190 | #endif |
| 191 | int o; |
| 192 | int width, height; |
| 193 | Uint8 *src, *map, *dst; |
| 194 | int srcskip, dstskip; |
| 195 | |
| 196 | /* Set up some basic variables */ |
| 197 | width = info->d_width; |
| 198 | height = info->d_height; |
| 199 | src = info->s_pixels; |
| 200 | srcskip = info->s_skip; |
| 201 | dst = info->d_pixels; |
| 202 | dstskip = info->d_skip; |
| 203 | map = info->table; |
| 204 | |
| 205 | while ( height-- ) { |
| 206 | #ifdef USE_DUFFS_LOOP |
| 207 | DUFFS_LOOP( |
| 208 | { |
| 209 | o = *src * 4; |
| 210 | dst[0] = map[o++]; |
| 211 | dst[1] = map[o++]; |
| 212 | dst[2] = map[o++]; |
| 213 | } |
| 214 | src++; |
| 215 | dst += 3; |
| 216 | , width); |
| 217 | #else |
| 218 | for ( c=width; c; --c ) { |
| 219 | o = *src * 4; |
| 220 | dst[0] = map[o++]; |
| 221 | dst[1] = map[o++]; |
| 222 | dst[2] = map[o++]; |
| 223 | src++; |
| 224 | dst += 3; |
| 225 | } |
| 226 | #endif /* USE_DUFFS_LOOP */ |
| 227 | src += srcskip; |
| 228 | dst += dstskip; |
| 229 | } |
| 230 | } |
| 231 | static void Blit1to4(SDL_BlitInfo *info) |
| 232 | { |
| 233 | #ifndef USE_DUFFS_LOOP |
| 234 | int c; |
| 235 | #endif |
| 236 | int width, height; |
| 237 | Uint8 *src; |
| 238 | Uint32 *map, *dst; |
| 239 | int srcskip, dstskip; |
| 240 | |
| 241 | /* Set up some basic variables */ |
| 242 | width = info->d_width; |
| 243 | height = info->d_height; |
| 244 | src = info->s_pixels; |
| 245 | srcskip = info->s_skip; |
| 246 | dst = (Uint32 *)info->d_pixels; |
| 247 | dstskip = info->d_skip/4; |
| 248 | map = (Uint32 *)info->table; |
| 249 | |
| 250 | while ( height-- ) { |
| 251 | #ifdef USE_DUFFS_LOOP |
| 252 | DUFFS_LOOP( |
| 253 | *dst++ = map[*src++]; |
| 254 | , width); |
| 255 | #else |
| 256 | for ( c=width/4; c; --c ) { |
| 257 | *dst++ = map[*src++]; |
| 258 | *dst++ = map[*src++]; |
| 259 | *dst++ = map[*src++]; |
| 260 | *dst++ = map[*src++]; |
| 261 | } |
| 262 | switch ( width & 3 ) { |
| 263 | case 3: |
| 264 | *dst++ = map[*src++]; |
| 265 | case 2: |
| 266 | *dst++ = map[*src++]; |
| 267 | case 1: |
| 268 | *dst++ = map[*src++]; |
| 269 | } |
| 270 | #endif /* USE_DUFFS_LOOP */ |
| 271 | src += srcskip; |
| 272 | dst += dstskip; |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | static void Blit1to1Key(SDL_BlitInfo *info) |
| 277 | { |
| 278 | int width = info->d_width; |
| 279 | int height = info->d_height; |
| 280 | Uint8 *src = info->s_pixels; |
| 281 | int srcskip = info->s_skip; |
| 282 | Uint8 *dst = info->d_pixels; |
| 283 | int dstskip = info->d_skip; |
| 284 | Uint8 *palmap = info->table; |
| 285 | Uint32 ckey = info->src->colorkey; |
| 286 | |
| 287 | if ( palmap ) { |
| 288 | while ( height-- ) { |
| 289 | DUFFS_LOOP( |
| 290 | { |
| 291 | if ( *src != ckey ) { |
| 292 | *dst = palmap[*src]; |
| 293 | } |
| 294 | dst++; |
| 295 | src++; |
| 296 | }, |
| 297 | width); |
| 298 | src += srcskip; |
| 299 | dst += dstskip; |
| 300 | } |
| 301 | } else { |
| 302 | while ( height-- ) { |
| 303 | DUFFS_LOOP( |
| 304 | { |
| 305 | if ( *src != ckey ) { |
| 306 | *dst = *src; |
| 307 | } |
| 308 | dst++; |
| 309 | src++; |
| 310 | }, |
| 311 | width); |
| 312 | src += srcskip; |
| 313 | dst += dstskip; |
| 314 | } |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | static void Blit1to2Key(SDL_BlitInfo *info) |
| 319 | { |
| 320 | int width = info->d_width; |
| 321 | int height = info->d_height; |
| 322 | Uint8 *src = info->s_pixels; |
| 323 | int srcskip = info->s_skip; |
| 324 | Uint16 *dstp = (Uint16 *)info->d_pixels; |
| 325 | int dstskip = info->d_skip; |
| 326 | Uint16 *palmap = (Uint16 *)info->table; |
| 327 | Uint32 ckey = info->src->colorkey; |
| 328 | |
| 329 | /* Set up some basic variables */ |
| 330 | dstskip /= 2; |
| 331 | |
| 332 | while ( height-- ) { |
| 333 | DUFFS_LOOP( |
| 334 | { |
| 335 | if ( *src != ckey ) { |
| 336 | *dstp=palmap[*src]; |
| 337 | } |
| 338 | src++; |
| 339 | dstp++; |
| 340 | }, |
| 341 | width); |
| 342 | src += srcskip; |
| 343 | dstp += dstskip; |
| 344 | } |
| 345 | } |
| 346 | |
| 347 | static void Blit1to3Key(SDL_BlitInfo *info) |
| 348 | { |
| 349 | int width = info->d_width; |
| 350 | int height = info->d_height; |
| 351 | Uint8 *src = info->s_pixels; |
| 352 | int srcskip = info->s_skip; |
| 353 | Uint8 *dst = info->d_pixels; |
| 354 | int dstskip = info->d_skip; |
| 355 | Uint8 *palmap = info->table; |
| 356 | Uint32 ckey = info->src->colorkey; |
| 357 | int o; |
| 358 | |
| 359 | while ( height-- ) { |
| 360 | DUFFS_LOOP( |
| 361 | { |
| 362 | if ( *src != ckey ) { |
| 363 | o = *src * 4; |
| 364 | dst[0] = palmap[o++]; |
| 365 | dst[1] = palmap[o++]; |
| 366 | dst[2] = palmap[o++]; |
| 367 | } |
| 368 | src++; |
| 369 | dst += 3; |
| 370 | }, |
| 371 | width); |
| 372 | src += srcskip; |
| 373 | dst += dstskip; |
| 374 | } |
| 375 | } |
| 376 | |
| 377 | static void Blit1to4Key(SDL_BlitInfo *info) |
| 378 | { |
| 379 | int width = info->d_width; |
| 380 | int height = info->d_height; |
| 381 | Uint8 *src = info->s_pixels; |
| 382 | int srcskip = info->s_skip; |
| 383 | Uint32 *dstp = (Uint32 *)info->d_pixels; |
| 384 | int dstskip = info->d_skip; |
| 385 | Uint32 *palmap = (Uint32 *)info->table; |
| 386 | Uint32 ckey = info->src->colorkey; |
| 387 | |
| 388 | /* Set up some basic variables */ |
| 389 | dstskip /= 4; |
| 390 | |
| 391 | while ( height-- ) { |
| 392 | DUFFS_LOOP( |
| 393 | { |
| 394 | if ( *src != ckey ) { |
| 395 | *dstp = palmap[*src]; |
| 396 | } |
| 397 | src++; |
| 398 | dstp++; |
| 399 | }, |
| 400 | width); |
| 401 | src += srcskip; |
| 402 | dstp += dstskip; |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | static void Blit1toNAlpha(SDL_BlitInfo *info) |
| 407 | { |
| 408 | int width = info->d_width; |
| 409 | int height = info->d_height; |
| 410 | Uint8 *src = info->s_pixels; |
| 411 | int srcskip = info->s_skip; |
| 412 | Uint8 *dst = info->d_pixels; |
| 413 | int dstskip = info->d_skip; |
| 414 | SDL_PixelFormat *dstfmt = info->dst; |
| 415 | const SDL_Color *srcpal = info->src->palette->colors; |
| 416 | int dstbpp; |
| 417 | const int A = info->src->alpha; |
| 418 | |
| 419 | /* Set up some basic variables */ |
| 420 | dstbpp = dstfmt->BytesPerPixel; |
| 421 | |
| 422 | while ( height-- ) { |
| 423 | int sR, sG, sB; |
| 424 | int dR, dG, dB; |
| 425 | DUFFS_LOOP4( |
| 426 | { |
| 427 | Uint32 pixel; |
| 428 | sR = srcpal[*src].r; |
| 429 | sG = srcpal[*src].g; |
| 430 | sB = srcpal[*src].b; |
| 431 | DISEMBLE_RGB(dst, dstbpp, dstfmt, |
| 432 | pixel, dR, dG, dB); |
| 433 | ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB); |
| 434 | ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB); |
| 435 | src++; |
| 436 | dst += dstbpp; |
| 437 | }, |
| 438 | width); |
| 439 | src += srcskip; |
| 440 | dst += dstskip; |
| 441 | } |
| 442 | } |
| 443 | |
| 444 | static void Blit1toNAlphaKey(SDL_BlitInfo *info) |
| 445 | { |
| 446 | int width = info->d_width; |
| 447 | int height = info->d_height; |
| 448 | Uint8 *src = info->s_pixels; |
| 449 | int srcskip = info->s_skip; |
| 450 | Uint8 *dst = info->d_pixels; |
| 451 | int dstskip = info->d_skip; |
| 452 | SDL_PixelFormat *srcfmt = info->src; |
| 453 | SDL_PixelFormat *dstfmt = info->dst; |
| 454 | const SDL_Color *srcpal = info->src->palette->colors; |
| 455 | Uint32 ckey = srcfmt->colorkey; |
| 456 | int dstbpp; |
| 457 | const int A = srcfmt->alpha; |
| 458 | |
| 459 | /* Set up some basic variables */ |
| 460 | dstbpp = dstfmt->BytesPerPixel; |
| 461 | |
| 462 | while ( height-- ) { |
| 463 | int sR, sG, sB; |
| 464 | int dR, dG, dB; |
| 465 | DUFFS_LOOP( |
| 466 | { |
| 467 | if ( *src != ckey ) { |
| 468 | Uint32 pixel; |
| 469 | sR = srcpal[*src].r; |
| 470 | sG = srcpal[*src].g; |
| 471 | sB = srcpal[*src].b; |
| 472 | DISEMBLE_RGB(dst, dstbpp, dstfmt, |
| 473 | pixel, dR, dG, dB); |
| 474 | ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB); |
| 475 | ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB); |
| 476 | } |
| 477 | src++; |
| 478 | dst += dstbpp; |
| 479 | }, |
| 480 | width); |
| 481 | src += srcskip; |
| 482 | dst += dstskip; |
| 483 | } |
| 484 | } |
| 485 | |
| 486 | static SDL_loblit one_blit[] = { |
| 487 | NULL, Blit1to1, Blit1to2, Blit1to3, Blit1to4 |
| 488 | }; |
| 489 | |
| 490 | static SDL_loblit one_blitkey[] = { |
| 491 | NULL, Blit1to1Key, Blit1to2Key, Blit1to3Key, Blit1to4Key |
| 492 | }; |
| 493 | |
| 494 | SDL_loblit SDL_CalculateBlit1(SDL_Surface *surface, int blit_index) |
| 495 | { |
| 496 | int which; |
| 497 | SDL_PixelFormat *dstfmt; |
| 498 | |
| 499 | dstfmt = surface->map->dst->format; |
| 500 | if ( dstfmt->BitsPerPixel < 8 ) { |
| 501 | which = 0; |
| 502 | } else { |
| 503 | which = dstfmt->BytesPerPixel; |
| 504 | } |
| 505 | switch(blit_index) { |
| 506 | case 0: /* copy */ |
| 507 | return one_blit[which]; |
| 508 | |
| 509 | case 1: /* colorkey */ |
| 510 | return one_blitkey[which]; |
| 511 | |
| 512 | case 2: /* alpha */ |
| 513 | /* Supporting 8bpp->8bpp alpha is doable but requires lots of |
| 514 | tables which consume space and takes time to precompute, |
| 515 | so is better left to the user */ |
| 516 | return which >= 2 ? Blit1toNAlpha : NULL; |
| 517 | |
| 518 | case 3: /* alpha + colorkey */ |
| 519 | return which >= 2 ? Blit1toNAlphaKey : NULL; |
| 520 | |
| 521 | } |
| 522 | return NULL; |
| 523 | } |