Mercurial > sdl-ios-xcode
annotate src/video/SDL_pixels.c @ 695:8f579a0e17e6
Whitespace
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 27 Aug 2003 04:53:40 +0000 |
| parents | c0522010bb6d |
| children | b8d311d90021 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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Updated copyright information for 2002
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3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 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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Updated the source with the correct e-mail address
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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 { | |
| 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 */ | |
|
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parents:
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382 unsigned v; |
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383 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
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parents:
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diff
changeset
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384 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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parents:
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385 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
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parents:
628
diff
changeset
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386 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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628
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parents:
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diff
changeset
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387 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
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c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
Sam Lantinga <slouken@libsdl.org>
parents:
628
diff
changeset
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388 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
| 0 | 389 if(fmt->Amask) { |
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parents:
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diff
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390 v = (pixel & fmt->Amask) >> fmt->Ashift; |
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Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
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parents:
628
diff
changeset
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391 *a = (v << fmt->Aloss) + (v >> (8 - (fmt->Aloss << 1))); |
| 695 | 392 } else { |
| 0 | 393 *a = SDL_ALPHA_OPAQUE; |
| 695 | 394 } |
| 0 | 395 } else { |
| 396 *r = fmt->palette->colors[pixel].r; | |
| 397 *g = fmt->palette->colors[pixel].g; | |
| 398 *b = fmt->palette->colors[pixel].b; | |
| 399 *a = SDL_ALPHA_OPAQUE; | |
| 400 } | |
| 401 } | |
| 402 | |
| 403 void SDL_GetRGB(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r,Uint8 *g,Uint8 *b) | |
| 404 { | |
| 405 if ( fmt->palette == NULL ) { | |
| 406 /* the note for SDL_GetRGBA above applies here too */ | |
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parents:
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407 unsigned v; |
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parents:
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408 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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688
c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
Sam Lantinga <slouken@libsdl.org>
parents:
628
diff
changeset
|
409 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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628
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parents:
297
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changeset
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410 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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688
c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
Sam Lantinga <slouken@libsdl.org>
parents:
628
diff
changeset
|
411 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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628
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parents:
297
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changeset
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412 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
|
688
c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
Sam Lantinga <slouken@libsdl.org>
parents:
628
diff
changeset
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413 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
| 0 | 414 } else { |
| 415 *r = fmt->palette->colors[pixel].r; | |
| 416 *g = fmt->palette->colors[pixel].g; | |
| 417 *b = fmt->palette->colors[pixel].b; | |
| 418 } | |
| 419 } | |
| 420 | |
| 421 /* Apply gamma to a set of colors - this is easy. :) */ | |
| 422 void SDL_ApplyGamma(Uint16 *gamma, SDL_Color *colors, SDL_Color *output, | |
| 423 int ncolors) | |
| 424 { | |
| 425 int i; | |
| 426 | |
| 427 for ( i=0; i<ncolors; ++i ) { | |
| 428 output[i].r = gamma[0*256 + colors[i].r] >> 8; | |
| 429 output[i].g = gamma[1*256 + colors[i].g] >> 8; | |
| 430 output[i].b = gamma[2*256 + colors[i].b] >> 8; | |
| 431 } | |
| 432 } | |
| 433 | |
| 434 /* Map from Palette to Palette */ | |
| 435 static Uint8 *Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical) | |
| 436 { | |
| 437 Uint8 *map; | |
| 438 int i; | |
| 439 | |
| 440 if ( identical ) { | |
| 441 if ( src->ncolors <= dst->ncolors ) { | |
| 442 /* If an identical palette, no need to map */ | |
| 443 if ( memcmp(src->colors, dst->colors, src->ncolors* | |
| 444 sizeof(SDL_Color)) == 0 ) { | |
| 445 *identical = 1; | |
| 446 return(NULL); | |
| 447 } | |
| 448 } | |
| 449 *identical = 0; | |
| 450 } | |
| 451 map = (Uint8 *)malloc(src->ncolors); | |
| 452 if ( map == NULL ) { | |
| 453 SDL_OutOfMemory(); | |
| 454 return(NULL); | |
| 455 } | |
| 456 for ( i=0; i<src->ncolors; ++i ) { | |
| 457 map[i] = SDL_FindColor(dst, | |
| 458 src->colors[i].r, src->colors[i].g, src->colors[i].b); | |
| 459 } | |
| 460 return(map); | |
| 461 } | |
| 462 /* Map from Palette to BitField */ | |
| 463 static Uint8 *Map1toN(SDL_Palette *src, SDL_PixelFormat *dst) | |
| 464 { | |
| 465 Uint8 *map; | |
| 466 int i; | |
| 467 int bpp; | |
| 50 | 468 unsigned alpha; |
| 0 | 469 |
| 470 bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel); | |
| 471 map = (Uint8 *)malloc(src->ncolors*bpp); | |
| 472 if ( map == NULL ) { | |
| 473 SDL_OutOfMemory(); | |
| 474 return(NULL); | |
| 475 } | |
| 476 | |
| 50 | 477 alpha = dst->Amask ? SDL_ALPHA_OPAQUE : 0; |
| 0 | 478 /* We memory copy to the pixel map so the endianness is preserved */ |
| 479 for ( i=0; i<src->ncolors; ++i ) { | |
| 480 ASSEMBLE_RGBA(&map[i*bpp], dst->BytesPerPixel, dst, | |
| 481 src->colors[i].r, src->colors[i].g, | |
| 50 | 482 src->colors[i].b, alpha); |
| 0 | 483 } |
| 484 return(map); | |
| 485 } | |
| 486 /* Map from BitField to Dithered-Palette to Palette */ | |
| 487 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical) | |
| 488 { | |
| 489 /* Generate a 256 color dither palette */ | |
| 490 SDL_Palette dithered; | |
| 491 SDL_Color colors[256]; | |
| 492 | |
| 493 dithered.ncolors = 256; | |
| 494 SDL_DitherColors(colors, 8); | |
| 495 dithered.colors = colors; | |
| 496 return(Map1to1(&dithered, dst, identical)); | |
| 497 } | |
| 498 | |
| 499 SDL_BlitMap *SDL_AllocBlitMap(void) | |
| 500 { | |
| 501 SDL_BlitMap *map; | |
| 502 | |
| 503 /* Allocate the empty map */ | |
| 504 map = (SDL_BlitMap *)malloc(sizeof(*map)); | |
| 505 if ( map == NULL ) { | |
| 506 SDL_OutOfMemory(); | |
| 507 return(NULL); | |
| 508 } | |
| 509 memset(map, 0, sizeof(*map)); | |
| 510 | |
| 511 /* Allocate the software blit data */ | |
| 512 map->sw_data = (struct private_swaccel *)malloc(sizeof(*map->sw_data)); | |
| 513 if ( map->sw_data == NULL ) { | |
| 514 SDL_FreeBlitMap(map); | |
| 515 SDL_OutOfMemory(); | |
| 516 return(NULL); | |
| 517 } | |
| 518 memset(map->sw_data, 0, sizeof(*map->sw_data)); | |
| 519 | |
| 520 /* It's ready to go */ | |
| 521 return(map); | |
| 522 } | |
| 523 void SDL_InvalidateMap(SDL_BlitMap *map) | |
| 524 { | |
| 525 if ( ! map ) { | |
| 526 return; | |
| 527 } | |
| 528 map->dst = NULL; | |
| 529 map->format_version = (unsigned int)-1; | |
| 530 if ( map->table ) { | |
| 531 free(map->table); | |
| 532 map->table = NULL; | |
| 533 } | |
| 534 } | |
| 535 int SDL_MapSurface (SDL_Surface *src, SDL_Surface *dst) | |
| 536 { | |
| 537 SDL_PixelFormat *srcfmt; | |
| 538 SDL_PixelFormat *dstfmt; | |
| 539 SDL_BlitMap *map; | |
| 540 | |
| 541 /* Clear out any previous mapping */ | |
| 542 map = src->map; | |
| 543 if ( (src->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { | |
| 544 SDL_UnRLESurface(src, 1); | |
| 545 } | |
| 546 SDL_InvalidateMap(map); | |
| 547 | |
| 548 /* Figure out what kind of mapping we're doing */ | |
| 549 map->identity = 0; | |
| 550 srcfmt = src->format; | |
| 551 dstfmt = dst->format; | |
| 552 switch (srcfmt->BytesPerPixel) { | |
| 553 case 1: | |
| 554 switch (dstfmt->BytesPerPixel) { | |
| 555 case 1: | |
| 556 /* Palette --> Palette */ | |
| 557 /* If both SDL_HWSURFACE, assume have same palette */ | |
| 558 if ( ((src->flags & SDL_HWSURFACE) == SDL_HWSURFACE) && | |
| 559 ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) ) { | |
| 560 map->identity = 1; | |
| 561 } else { | |
| 562 map->table = Map1to1(srcfmt->palette, | |
| 563 dstfmt->palette, &map->identity); | |
| 564 } | |
| 565 if ( ! map->identity ) { | |
| 566 if ( map->table == NULL ) { | |
| 567 return(-1); | |
| 568 } | |
| 569 } | |
| 570 if (srcfmt->BitsPerPixel!=dstfmt->BitsPerPixel) | |
| 571 map->identity = 0; | |
| 572 break; | |
| 573 | |
| 574 default: | |
| 575 /* Palette --> BitField */ | |
| 576 map->table = Map1toN(srcfmt->palette, dstfmt); | |
| 577 if ( map->table == NULL ) { | |
| 578 return(-1); | |
| 579 } | |
| 580 break; | |
| 581 } | |
| 582 break; | |
| 583 default: | |
| 584 switch (dstfmt->BytesPerPixel) { | |
| 585 case 1: | |
| 586 /* BitField --> Palette */ | |
| 587 map->table = MapNto1(srcfmt, | |
| 588 dstfmt->palette, &map->identity); | |
| 589 if ( ! map->identity ) { | |
| 590 if ( map->table == NULL ) { | |
| 591 return(-1); | |
| 592 } | |
| 593 } | |
| 594 map->identity = 0; /* Don't optimize to copy */ | |
| 595 break; | |
| 596 default: | |
| 597 /* BitField --> BitField */ | |
| 598 if ( FORMAT_EQUAL(srcfmt, dstfmt) ) | |
| 599 map->identity = 1; | |
| 600 break; | |
| 601 } | |
| 602 break; | |
| 603 } | |
| 604 | |
| 605 map->dst = dst; | |
| 606 map->format_version = dst->format_version; | |
| 607 | |
| 608 /* Choose your blitters wisely */ | |
| 609 return(SDL_CalculateBlit(src)); | |
| 610 } | |
| 611 void SDL_FreeBlitMap(SDL_BlitMap *map) | |
| 612 { | |
| 613 if ( map ) { | |
| 614 SDL_InvalidateMap(map); | |
| 615 if ( map->sw_data != NULL ) { | |
| 616 free(map->sw_data); | |
| 617 } | |
| 618 free(map); | |
| 619 } | |
| 620 } |