src/anim/animplay.cpp

   1 /*
   2  * Copyright (C) Volition, Inc. 1999.  All rights reserved.
   3  *
   4  * All source code herein is the property of Volition, Inc. You may not sell
   5  * or otherwise commercially exploit the source or things you created based on
   6  * the source.
   7  */
   8
   9 /*
  10  * $Logfile: /Freespace2/code/Anim/AnimPlay.cpp $
  11  * $Revision$
  12  * $Date$
  13  * $Author$
  14  *
  15  * C module for playing back anim files
  16  *
  17  * $Log$
  18  * Revision 1.7  2006/04/26 19:48:58  taylor
  19  * various big-endian fixes, mainly networking support related
  20  *
  21  * Revision 1.6  2005/08/12 08:55:13  taylor
  22  * sync up talking head fixes from FS2_Open code base (still not 100%)
  23  *
  24  * Revision 1.5  2004/09/20 01:31:44  theoddone33
  25  * GCC 3.4 fixes.
  26  *
  27  * Revision 1.4  2004/06/11 00:27:06  tigital
  28  * byte-swapping changes for bigendian systems
  29  *
  30  * Revision 1.3  2002/06/09 04:41:15  relnev
  31  * added copyright header
  32  *
  33  * Revision 1.2  2002/05/07 03:16:43  theoddone33
  34  * The Great Newline Fix
  35  *
  36  * Revision 1.1.1.1  2002/05/03 03:28:08  root
  37  * Initial import.
  38  *
  39  *
  40  * 9     9/13/99 11:26p Andsager
  41  * Add debug code to check for poorly sized anis
  42  *
  43  * 8     8/26/99 9:45a Dave
  44  * First pass at easter eggs and cheats.
  45  *
  46  * 7     7/16/99 1:49p Dave
  47  * 8 bit aabitmaps. yay.
  48  *
  49  * 6     7/13/99 1:15p Dave
  50  * 32 bit support. Whee!
  51  *
  52  * 5     6/10/99 10:34a Dave
  53  * Removed unnecessary assert.
  54  *
  55  * 4     11/30/98 1:07p Dave
  56  * 16 bit conversion, first run.
  57  *
  58  * 3     10/22/98 6:14p Dave
  59  * Optimized some #includes in Anim folder. Put in the beginnings of
  60  * parse/localization support for externalized strings and tstrings.tbl
  61  *
  62  * 2     10/07/98 10:52a Dave
  63  * Initial checkin.
  64  *
  65  * 1     10/07/98 10:48a Dave
  66  *
  67  * 38    6/23/98 4:18p Hoffoss
  68  * Fixed some bugs with AC release build.
  69  *
  70  * 37    5/18/98 5:59p Hoffoss
  71  * Made command briefing advanced now once the speech stops and animation
  72  * has fully played once, whichever is longer.
  73  *
  74  * 36    5/14/98 6:29p Hoffoss
  75  * Fixed some warnings a release rebuild all turned up.
  76  *
  77  * 35    5/07/98 3:11a Lawrance
  78  * Implement custom streaming code
  79  *
  80  * 34    4/27/98 3:36p Dave
  81  *
  82  * 33    3/25/98 8:43p Hoffoss
  83  * Changed anim_play() to not be so damn complex when you try and call it.
  84  *
  85  * 32    2/05/98 9:21p John
  86  * Some new Direct3D code.   Added code to monitor a ton of stuff in the
  87  * game.
  88  *
  89  * 31    1/19/98 11:37p Lawrance
  90  * Fixing Optimization build warnings
  91  *
  92  * 30    1/19/98 3:09p Hoffoss
  93  * Only free an anim instance if it is actually playing.
  94  *
  95  * 29    1/14/98 6:43p Lawrance
  96  * Add ref_count to anim struct, so we don't free multiple times
  97  *
  98  * 28    12/30/97 6:44p John
  99  * Made g3_Draw_bitmap functions account for aspect of bitmap.
 100  *
 101  * 27    12/27/97 2:35p John
 102  * Restructed some code so that if the memory-mapped file open fails, it
 103  * will still read it the old-fashioned, non-memory mapped way.
 104  *
 105  * 26    12/24/97 9:10p Lawrance
 106  * take out some debugging statements
 107  *
 108  * 25    12/24/97 8:57p Lawrance
 109  * Added anim_ignore_next_frametime()
 110  *
 111  * 24    12/07/97 2:06p Dave
 112  * Removed some debug frame-checking code.
 113  *
 114  * 23    12/06/97 2:55p Dave
 115  *
 116  * 22    11/29/97 2:05p John
 117  * made g3_draw_bitmap and g3_draw_rotated bitmap take w&h, not w/2 & h/2,
 118  * like they used to incorrectly assume.   Added code to model to read in
 119  * thruster radius's.
 120  *
 121  * 21    11/20/97 5:36p Dave
 122  * Hooked in a bunch of main hall changes (including sound). Made it
 123  * possible to reposition (rewind/ffwd)
 124  * sound buffer pointers. Fixed animation direction change framerate
 125  * problem.
 126  *
 127  * 20    11/20/97 4:33p Sandeep
 128  * ALAN: ensure instance->paused gets initialized
 129  *
 130  * 19    11/20/97 4:12p Lawrance
 131  * when paused, don't increment time_elapsed
 132  *
 133  * 18    11/19/97 8:28p Dave
 134  * Hooked in Main Hall screen. Put in Anim support for ping ponging
 135  * animations as well as general reversal of anim direction.
 136  *
 137  * 17    9/11/97 4:17p Allender
 138  * use _MAX_PATH instead of MAX_FILENAME_LENGTH for anim_play since it is
 139  * called from MoviePlayer with full path
 140  *
 141  * 16    9/11/97 10:49a Lawrance
 142  * improve anim_show_next_frame()
 143  *
 144  * 15    9/10/97 4:59p Lawrance
 145  * improve comments to anim_play() function
 146  *
 147  * 14    9/03/97 4:19p John
 148  * changed bmpman to only accept ani and pcx's.  made passing .pcx or .ani
 149  * to bm_load functions not needed.   Made bmpman keep track of palettes
 150  * for bitmaps not mapped into game palettes.
 151  *
 152  * 13    8/30/97 2:11p Lawrance
 153  * allow animations to loop
 154  *
 155  * 12    8/25/97 11:13p Lawrance
 156  * support framerate independent playback with the option of now advancing
 157  * more than one frame at a time
 158  *
 159  * 11    8/22/97 8:20a Lawrance
 160  * display scrolling text properly, with indicator that text exitsts to be
 161  * scrolled
 162  *
 163  * 10    8/21/97 5:11p Lawrance
 164  * frame numbering for ANI's now is from 0 -> total_frames-1.
 165  *
 166  * 9     8/19/97 9:30a Lawrance
 167  * print out reason if file doesn't open right
 168  *
 169  * 8     7/28/97 10:42p Lawrance
 170  * re-did interface to unpack_frame() to make more general
 171  *
 172  * 7     7/21/97 11:41a Lawrance
 173  * make playback time of .ani files keyed of frametime
 174  *
 175  * 6     7/20/97 6:57p Lawrance
 176  * supporting new RLE format
 177  *
 178  * 5     7/11/97 11:54a John
 179  * added rotated 3d bitmaps.
 180  *
 181  * 4     6/27/97 4:36p Lawrance
 182  * update pal translation table when gr_screen.signature changes
 183  *
 184  * 3     6/26/97 3:00p Lawrance
 185  * fix bug with playing 3d anims
 186  *
 187  * 2     6/26/97 12:12a Lawrance
 188  * supporting anti-aliased bitmap animations
 189  *
 190  * 1     6/23/97 5:09p Lawrance
 191  *
 192  * 24    6/03/97 5:53p Lawrance
 193  * don't unload bitmap after bm_create
 194  *
 195  * $NoKeywords: $
 196  */
 197
 198 #include "animplay.h"
 199 #include "linklist.h"
 200 #include "timer.h"
 201 #include "bmpman.h"
 202 #include "2d.h"
 203 #include "3d.h"
 204 #include "grinternal.h"
 205 #include "pcxutils.h"
 206 #include "packunpack.h"
 207 #include "cfile.h"
 208
 209 static color Color_xparent;
 210
 211 anim *first_anim = NULL;
 212 anim_instance anim_free_list;
 213 anim_instance anim_render_list;
 214
 215 #define MAX_ANIM_INSTANCES 25
 216 anim_instance anim_render_instance[MAX_ANIM_INSTANCES];
 217
 218 int Anim_paused;        // global variable to pause the playing back of anims
 219 int Anim_inited = FALSE;
 220
 221 fix t1,t2;
 222
 223 int Anim_ignore_frametime=0;    // flag used to ignore frametime... useful when need to avoid saturated frametimes
 224
 225 // -------------------------------------------------------------------------------------------------
 226 // anim_init() will queue all the anim_render_instance[] elements onto the anim_free_list
 227 //
 228 void anim_init()
 229 {
 230         int i;
 231
 232         if ( Anim_inited == TRUE )
 233                 return;
 234
 235         list_init( &anim_free_list );
 236         list_init( &anim_render_list );
 237
 238         // Link all anim render slots into the free list
 239         for (i=1; i < MAX_ANIM_INSTANCES; i++)  {
 240                 list_append(&anim_free_list, &anim_render_instance[i]);
 241         }
 242
 243         Anim_paused = 0;
 244         Anim_inited = TRUE;
 245 }
 246
 247 // -------------------------------------------------------------------------------------------------
 248 // anim_render_all() will display the frames for the currently playing anims
 249 //
 250 void anim_render_all(int screen_id, float frametime)
 251 {
 252         anim_instance* A;
 253         anim_instance* temp;
 254
 255         A = GET_FIRST(&anim_render_list);
 256         while( A !=END_OF_LIST(&anim_render_list) )     {
 257                 temp = GET_NEXT(A);
 258                 if ( A->screen_id == screen_id ) {
 259                         if ( Anim_ignore_frametime ) {
 260                                 frametime = 0.0f;
 261                                 Anim_ignore_frametime=0;
 262                         }
 263                         if ( anim_show_next_frame(A, frametime) == -1 ) {
 264                                 A->data = NULL;
 265                                 anim_release_render_instance(A);
 266                         }
 267                 }
 268                 A = temp;
 269         }
 270 }
 271
 272 // -------------------------------------------------------------------------------------------------
 273 // anim_render_one() will display the frames for the passed animation, it will ignore animations which
 274 // do not have the same id as the passed screen_id
 275 //
 276 void anim_render_one(int screen_id, anim_instance *ani, float frametime)
 277 {
 278         // make sure this guy's screen id matches the passed one
 279         if(screen_id != ani->screen_id){
 280                 return;
 281         }
 282
 283         // otherwise render it
 284         if ( Anim_ignore_frametime ) {
 285                 frametime = 0.0f;
 286                 Anim_ignore_frametime=0;
 287         }
 288         if ( anim_show_next_frame(ani, frametime) == -1 ) {
 289                 ani->data = NULL;
 290                 anim_release_render_instance(ani);
 291         }
 292 }
 293
 294 MONITOR(NumANIPlayed);
 295
 296 // Setup an anim_play_struct for passing into anim_play().  Will fill in default values, which you
 297 // can then change before calling anim_play().
 298 //
 299 void anim_play_init(anim_play_struct *aps, anim *a_info, int x, int y)
 300 {
 301         aps->anim_info = a_info;
 302         aps->x = x;
 303         aps->y = y;
 304         aps->start_at = 0;
 305         aps->stop_at = a_info->total_frames - 1;
 306         aps->screen_id = 0;
 307         aps->world_pos = NULL;
 308         aps->radius = 0.0f;
 309         aps->framerate_independent = 0;
 310         aps->color = NULL;
 311         aps->skip_frames = 1;
 312         aps->looped = 0;
 313         aps->ping_pong = 0;
 314 }
 315
 316 // -------------------------------------------------------------------------------------------------
 317 // anim_play() will add an anim instance to the anim_render_list.  This will cause the
 318 // anim to be played at the x,y position specified in the parameter list.
 319 //
 320 // input:
 321 //
 322 //              anim_info       =>      the compressed animation that we should make an instance from
 323 //              x                               =>      x position of animation to play at (top left corner)
 324 //              y                               =>      y position of animation to play at ( top left corner)
 325 //              start_at                =>      frame number to start at (note: numbering is from 0->num_frames-1)
 326 //              stop_at         =>      frame number to stop at (note: numbering is from 0->num_frames-1)
 327 //              screen_id       =>      OPTIONAL (default value 0): screen signature so animation only plays when
 328 //                                                      anim_render_all() called with that same signature
 329 //              world_pos       =>      OPTIONAL (default value NULL): only give a world pos when you want to
 330 //                                                      play the animation at a 3D location.  You must specify radius when
 331 //                                                      this is non-null.
 332 //              radius          =>      OPTIONAL (default value 0): only needed when the animation is playing
 333 //                                                      as a 3D animation (this is only when world_pos in not NULL).
 334 //              fi                              =>      OPTIONAL (default value 0): framerate indepentdent flag, when set TRUE
 335 //                                                      the animation will skip frames if necessary to maintain the fps value
 336 //                                                      associated with the animation
 337 //              color                   =>      OPTIONAL (default value NULL) address of an alpha color struct.  Only
 338 //                                                      required when the animation should be drawn with an alpha color.
 339 //              skip_frames     => OPTIONAL (default value 1) should anim skip frames when doing framerate
 340 //                   independent playback
 341 //              looped          =>      OPTIONAL (default value 0) should anim play looped (ie forever)
 342 //
 343 // returns:
 344 //
 345 //              pointer to instance     => success
 346 //              NULL                                            => if anim anim could not be played
 347 //
 348 anim_instance *anim_play(anim_play_struct *aps)
 349 {
 350         SDL_assert( aps->anim_info != NULL );
 351         SDL_assert( aps->start_at >= 0 );
 352         SDL_assert( aps->stop_at < aps->anim_info->total_frames );
 353         // SDL_assert( aps->stop_at >= aps->start_at );
 354         SDL_assert( !(aps->looped && aps->ping_pong) );  // shouldn't have these both set at once
 355
 356         MONITOR_INC(NumANIPlayed, 1);
 357
 358         // if (aps->ping_pong && !(aps->anim_info->flags & ANF_ALL_KEYFRAMES));
 359
 360         anim_instance *instance;
 361
 362         // Find next free anim instance slot on queue
 363         instance = GET_FIRST(&anim_free_list);
 364         SDL_assert( instance != &anim_free_list );  // shouldn't have the dummy element
 365
 366         // remove instance from the free list
 367         list_remove( &anim_free_list, instance );
 368
 369         // insert instance onto the end of anim_render_list
 370         list_append( &anim_render_list, instance );
 371
 372         aps->anim_info->instance_count++;
 373         instance->frame_num = -1;
 374         instance->last_frame_num = -99;
 375         instance->parent = aps->anim_info;
 376         instance->data = aps->anim_info->data;
 377         if ( anim_instance_is_streamed(instance) ) {
 378                 instance->file_offset = instance->parent->file_offset;
 379         }
 380         instance->frame = (ubyte *) malloc(instance->parent->width * instance->parent->height * 2);
 381         SDL_assert( instance->frame != NULL );
 382         instance->time_elapsed = 0.0f;
 383         instance->stop_at = aps->stop_at;
 384         instance->x = aps->x;
 385         instance->y = aps->y;
 386         instance->world_pos = aps->world_pos;
 387         instance->radius = aps->radius;
 388         instance->framerate_independent = aps->framerate_independent;
 389         instance->last_bitmap = -1;
 390         instance->stop_now = FALSE;
 391         instance->screen_id = aps->screen_id;
 392         instance->aa_color = aps->color;
 393         instance->skip_frames = aps->skip_frames;
 394         instance->looped = aps->looped;
 395         instance->ping_pong = aps->ping_pong;
 396         instance->direction = ANIM_DIRECT_FORWARD;
 397         instance->paused = 0;
 398         instance->loop_count = 0;
 399         if ( aps->color == NULL ){
 400                 instance->xlate_pal = 1;
 401         } else {
 402                 instance->xlate_pal = 0;
 403         }
 404
 405         // determining the start_at frame is more complicated, since it must be a key-frame.
 406         // Futhermore, need to subtract 1 from key-frame number, since frame number is always
 407         // incremented the first time anim_show_next_frame() is called
 408
 409         instance->start_at = aps->start_at;
 410
 411         if ( aps->start_at > 0 ) {
 412                 key_frame *keyp;
 413                 int idx;
 414                 int key = 0;
 415                 int offset = 0;
 416                 int frame_num = aps->start_at;
 417
 418                 keyp = instance->parent->keys;
 419                 idx = 0;
 420                 while (idx < instance->parent->num_keys) {
 421                         if (key == frame_num)
 422                                 break;
 423
 424                         key = keyp[idx].frame_num - 1;
 425                         offset = keyp[idx].offset;
 426
 427                         idx++;
 428                 }
 429                 /*while (keyp) {
 430                         if (( (keyp->frame_num-1) <= frame_num) && ( (keyp->frame_num-1) > key)) {  // find closest key
 431                                 key = keyp->frame_num-1;
 432                                 offset = keyp->offset;
 433                                 if ( key == frame_num )
 434                                         break;
 435                         }
 436
 437                         keyp = keyp->next;
 438                 }*/
 439
 440                 if (key > instance->frame_num) {  // best key is closer than current position
 441                         instance->frame_num = key;
 442                         if ( anim_instance_is_streamed(instance) ) {
 443                                 instance->file_offset = instance->parent->file_offset + offset;
 444                         } else {
 445                                 instance->data = instance->parent->data + offset;
 446                         }
 447
 448                 }
 449
 450                 instance->frame_num--;  // required
 451         }
 452
 453         return instance;
 454 }
 455
 456 // -----------------------------------------------------------------------------
 457 //      anim_show_next_frame()
 458 //
 459 //      This function is called to blit the next frame of an anim instance to the
 460 // screen.  This is normally called by the anim_render_all() function.
 461 //
 462 //      input:  instance                =>              pointer to animation instance
 463 //                              frametime       =>              time elapsed since last call, in seconds
 464 //
 465 int anim_show_next_frame(anim_instance *instance, float frametime)
 466 {
 467         int             bitmap_id, bitmap_flags=0, new_frame_num, frame_diff=0, i, n_frames=0,frame_save;
 468         float           percent_through, decompress_time, render_time, time;
 469         vertex  image_vertex;
 470         int aabitmap = 0;
 471         int bpp = 16;
 472
 473         SDL_assert( instance != NULL );
 474
 475         instance->time_elapsed += frametime;
 476
 477         // Advance to the next frame, if we determine enough time has elapsed.
 478         if(instance->direction == ANIM_DIRECT_FORWARD)
 479                 n_frames = instance->stop_at - instance->start_at + 1;
 480         else if(instance->direction == ANIM_DIRECT_REVERSE)
 481                 n_frames = instance->start_at - instance->stop_at + 1;
 482         time = n_frames / i2fl(instance->parent->fps);
 483
 484         percent_through = instance->time_elapsed / time;
 485
 486         if(instance->direction == ANIM_DIRECT_FORWARD)
 487                 new_frame_num = instance->start_at - 1 + fl2i(percent_through * n_frames + 0.5f);
 488         else
 489                 new_frame_num = instance->start_at - 1 - fl2i(percent_through * n_frames + 0.5f);
 490
 491         frame_save = instance->frame_num;
 492
 493         // If framerate independent, use the new_frame_num... unless instance->skip_frames is
 494         // FALSE, then only advance a maximum of one frame (this is needed since some big animations
 495         // should just play slower rather than taking the hit of decompressing multiple frames and
 496         // creating an even greater slowdown
 497         if (instance->framerate_independent) {
 498                 if(instance->direction == ANIM_DIRECT_FORWARD){
 499                         if ( new_frame_num > instance->last_frame_num) {
 500                                 if ( instance->skip_frames )
 501                                         instance->frame_num = new_frame_num;
 502                                 else
 503                                         instance->frame_num++;
 504                         }
 505                 } else if(instance->direction == ANIM_DIRECT_REVERSE){
 506                         if( new_frame_num < instance->last_frame_num) {
 507                                 if ( instance->skip_frames )
 508                                         instance->frame_num = new_frame_num;
 509                                 else
 510                                         instance->frame_num--;
 511                         }
 512                 }
 513         }
 514         else {
 515                 if(instance->direction == ANIM_DIRECT_FORWARD){
 516                         if ( new_frame_num > instance->last_frame_num) {
 517                                 instance->frame_num++;
 518                         }
 519                 } else if(instance->direction == ANIM_DIRECT_REVERSE){
 520                         if ( new_frame_num < instance->last_frame_num) {
 521                                 instance->frame_num--;
 522                         }
 523                 }
 524         }
 525
 526         if(instance->direction == ANIM_DIRECT_FORWARD){
 527                 if ( instance->frame_num < instance->start_at ) {
 528                         instance->frame_num = instance->start_at;
 529                 }
 530         } else if(instance->direction == ANIM_DIRECT_REVERSE){
 531                 if ( instance->frame_num > instance->start_at ) {
 532                         instance->frame_num = instance->start_at;
 533                 }
 534         }
 535
 536         if ( instance->stop_now == TRUE ) {
 537                 return -1;
 538         }
 539
 540         // If past the last frame, clamp to the last frame and then set the stop_now flag in the
 541         // anim instance.  The next iteration, the animation will stop.
 542         if(instance->direction == ANIM_DIRECT_FORWARD){
 543                 if (instance->frame_num >= instance->stop_at ) {
 544                         if (instance->looped) {                                                                         // looped animations
 545                                 instance->frame_num = instance->stop_at;
 546                                 instance->time_elapsed = 0.0f;
 547                         } else if(instance->ping_pong) {                                                        // pingponged animations
 548                                 instance->frame_num = instance->stop_at;
 549                                 // instance->time_elapsed = 0.0f;
 550                                 anim_reverse_direction(instance);
 551                         } else {                                                                                                                        // one-shot animations
 552                                 instance->frame_num = instance->stop_at;
 553                                 instance->last_frame_num = instance->frame_num;
 554                                 instance->stop_now = TRUE;
 555                         }
 556                 }
 557         } else if(instance->direction == ANIM_DIRECT_REVERSE){
 558                 if (instance->frame_num <= instance->stop_at ) {
 559                         if (instance->looped) {                                                                         // looped animations
 560                                 instance->frame_num = instance->stop_at;
 561                                 instance->time_elapsed = 0.0f;
 562                         } else if(instance->ping_pong) {                                                        // pingponged animations
 563                                 instance->frame_num = instance->stop_at;
 564                                 // instance->time_elapsed = 0.0f;
 565                                 anim_reverse_direction(instance);
 566                         } else {                                                                                                                        // one-shot animations
 567                                 instance->frame_num = instance->stop_at+1;
 568                                 instance->last_frame_num = instance->frame_num;
 569                                 instance->stop_now = TRUE;
 570                         }
 571                 }
 572         }
 573
 574         if(instance->direction == ANIM_DIRECT_FORWARD){
 575                 if( instance->last_frame_num >= instance->start_at ) {
 576                         frame_diff = instance->frame_num - instance->last_frame_num;
 577                 } else {
 578                         frame_diff = 1;
 579                 }
 580         } else if(instance->direction == ANIM_DIRECT_REVERSE){
 581                 if( instance->last_frame_num <= instance->start_at ) {
 582                         frame_diff = instance->last_frame_num - instance->frame_num;
 583                 } else {
 584                         frame_diff = 1;
 585                 }
 586         }
 587         SDL_assert(frame_diff >= 0);
 588         //      nprintf(("Alan","FRAME DIFF: %d\n",frame_diff));
 589         SDL_assert( instance->frame_num >= 0 && instance->frame_num < instance->parent->total_frames );
 590
 591         // if the anim is paused, ignore all the above changes and still display this frame
 592         if(instance->paused || Anim_paused){
 593                 instance->frame_num = frame_save;
 594                 instance->time_elapsed -= frametime;
 595                 frame_diff = 0;
 596         }
 597
 598         if (instance->parent->flags & ANF_XPARENT){
 599                 // bitmap_flags = BMP_XPARENT;
 600                 bitmap_flags = 0;
 601         }
 602         bpp = 16;
 603         if(instance->aa_color != NULL){
 604                 bitmap_flags |= BMP_AABITMAP;
 605                 aabitmap = 1;
 606                 bpp = 8;
 607         }
 608
 609         if ( frame_diff > 0 ) {
 610                 instance->last_frame_num = instance->frame_num;
 611
 612                 t1 = timer_get_fixed_seconds();
 613                 for ( i = 0; i < frame_diff; i++ ) {
 614                         anim_check_for_palette_change(instance);
 615
 616                         // if we're playing backwards, every frame must be a keyframe and we set the data ptr here
 617                         if(instance->direction == ANIM_DIRECT_REVERSE){
 618                                 if ( anim_instance_is_streamed(instance) ) {
 619                                         instance->file_offset = instance->parent->file_offset + instance->parent->keys[instance->frame_num-1].offset;
 620                                 } else {
 621                                         instance->data = instance->parent->data + instance->parent->keys[instance->frame_num-1].offset;
 622                                 }
 623                         }
 624
 625                         ubyte *temp = NULL;
 626                         int temp_file_offset = 0;
 627
 628                         BM_SELECT_TEX_FORMAT();
 629
 630                         if ( anim_instance_is_streamed(instance) ) {
 631                                 if ( instance->xlate_pal ){
 632                                         temp_file_offset = unpack_frame_from_file(instance, instance->frame, instance->parent->width*instance->parent->height, instance->parent->palette_translation, aabitmap, bpp);
 633                                 } else {
 634                                         temp_file_offset = unpack_frame_from_file(instance, instance->frame, instance->parent->width*instance->parent->height, NULL, aabitmap, bpp);
 635                                 }
 636                         } else {
 637                                 if ( instance->xlate_pal ){
 638                                         temp = unpack_frame(instance, instance->data, instance->frame, instance->parent->width*instance->parent->height, instance->parent->palette_translation, aabitmap, bpp);
 639                                 } else {
 640                                         temp = unpack_frame(instance, instance->data, instance->frame, instance->parent->width*instance->parent->height, NULL, aabitmap, bpp);
 641                                 }
 642                         }
 643
 644                         // always go back to screen format
 645                         BM_SELECT_SCREEN_FORMAT();
 646
 647                         if(instance->direction == ANIM_DIRECT_FORWARD){
 648                                 if ( anim_instance_is_streamed(instance) ) {
 649                                         instance->file_offset = temp_file_offset;
 650                                 } else {
 651                                         instance->data = temp;
 652                                 }
 653                         }
 654                 }
 655                 t2 = timer_get_fixed_seconds();
 656         }
 657         else {
 658                 t2=t1=0;
 659         }
 660
 661         // this only happens when the anim is being looped, we need to reset the last_frame_num
 662         if ( (instance->time_elapsed == 0) && (instance->looped) ) {
 663                 instance->last_frame_num = -1;
 664                 instance->frame_num = -1;
 665                 instance->data = instance->parent->data;
 666                 instance->file_offset = instance->parent->file_offset;
 667                 instance->loop_count++;
 668         }
 669
 670         decompress_time = f2fl(t2-t1);
 671
 672         t1 = timer_get_fixed_seconds();
 673         if ( frame_diff == 0 && instance->last_bitmap != -1 ) {
 674                 bitmap_id = instance->last_bitmap;
 675         }
 676         else {
 677                 if ( instance->last_bitmap != -1 ){
 678                         bm_release(instance->last_bitmap);
 679                 }
 680                 bitmap_id = bm_create(16, instance->parent->width, instance->parent->height, instance->frame, bitmap_flags);
 681         }
 682
 683         if ( bitmap_id == -1 ) {
 684                 // anim has finsished playing, free the instance frame data
 685                 anim_release_render_instance(instance);
 686                 return -1;
 687
 688                 // NOTE: there is no need to free the instance, since it was pre-allocated as
 689                 //       part of the anim_free_list
 690         }
 691         else {
 692                 gr_set_bitmap(bitmap_id, GR_ALPHABLEND_NONE, GR_BITBLT_MODE_NORMAL, 1.0f, -1, -1);
 693
 694                 // determine x,y to display the bitmap at
 695                 if ( instance->world_pos == NULL ) {
 696                         if ( instance->aa_color == NULL ) {
 697                                 gr_bitmap(instance->x, instance->y);
 698                         }
 699                         else {
 700                                 gr_set_color_fast( (color*)instance->aa_color );
 701                                 gr_aabitmap(instance->x, instance->y);
 702                         }
 703                 }
 704                 else {
 705                         g3_rotate_vertex(&image_vertex,instance->world_pos);
 706                         SDL_assert(instance->radius != 0.0f);
 707                         g3_draw_bitmap(&image_vertex, 0, instance->radius*1.5f, TMAP_FLAG_TEXTURED );
 708                 }
 709
 710                 //bm_release(bitmap_id);
 711                 instance->last_bitmap = bitmap_id;
 712         }
 713
 714         t2 = timer_get_fixed_seconds();
 715         render_time = f2fl(t2-t1);
 716
 717 //      nprintf(("Alan","DECOMPRESS: %.3fms  RENDER: %.3fms\n", decompress_time*1000, render_time*1000));
 718
 719         return 0;
 720 }
 721
 722 // -----------------------------------------------------------------------------
 723 //      anim_stop_playing()
 724 //
 725 //      Stop an anim instance that is on the anim_render_list from playing
 726 //
 727 int anim_stop_playing(anim_instance* instance)
 728 {
 729         SDL_assert(instance != NULL);
 730
 731         if ( anim_playing(instance) ) {
 732                 anim_release_render_instance(instance);
 733         }
 734         return 0;
 735 }
 736
 737 // -----------------------------------------------------------------------------
 738 //      anim_release_render_instance()
 739 //
 740 //      Free a particular animation instance that is on the anim_render_list.  Do
 741 // not call this function to free an animation instance in general (use
 742 // free_anim_instance() for that), only when you want to free an instance
 743 // that is on the anim_render_list
 744 //
 745 void anim_release_render_instance(anim_instance* instance)
 746 {
 747         SDL_assert( instance != NULL );
 748         SDL_assert(instance->frame);
 749         free(instance->frame);
 750         instance->frame = NULL;
 751         instance->parent->instance_count--;
 752
 753         if ( instance->last_bitmap != -1 ) {
 754                 bm_release(instance->last_bitmap);
 755                 instance->last_bitmap = -1;
 756         }
 757
 758         // remove instance from anim_render_list
 759         list_remove( &anim_render_list, instance );
 760
 761         // insert instance into the anim_free_list
 762         list_append( &anim_free_list, instance );
 763 }
 764
 765 // -----------------------------------------------------------------------------
 766 //      anim_release_all_instances()
 767 //
 768 //      Free all anim instances that are on the anim_render_list.
 769 //
 770 //      input:  screen_id       =>              optional parameter that lets you only free a subset
 771 //                                                                              of the anim instances.  A screen_id of 0 is the default
 772 //                                                                              value, and this is used for animations that always play
 773 //                                                                              when they are placed on the aim_render_list.
 774 //
 775 void anim_release_all_instances(int screen_id)
 776 {
 777         anim_instance* A;
 778         anim_instance* temp;
 779
 780         if ( Anim_inited == FALSE )
 781                 return;
 782
 783         A = GET_FIRST(&anim_render_list);
 784         while( A !=END_OF_LIST(&anim_render_list) )     {
 785                 temp = GET_NEXT(A);
 786                 if ( A->screen_id == screen_id || screen_id == 0 ) {
 787                         anim_release_render_instance(A);
 788                 }
 789                 A = temp;
 790         }
 791 }
 792
 793 // -----------------------------------------------------------------------------
 794 //      anim_read_header()
 795 //
 796 // Read the header of a .ani file.  Below is the format of a .ani header
 797 //
 798 //      #bytes  |       description
 799 //      2                       |       obsolete, kept for compatibility with old versions
 800 //      2                       |       version number
 801 //      2                       |       fps
 802 //      1                       |       transparent red value
 803 //      1                       |       transparent green value
 804 //      1                       |       transparent blue value
 805 //      2                       |       width
 806 //      2                       |       height
 807 //      2                       |       number of frames
 808 //      2                       |       packer code
 809 //      763                     |       palette
 810 //      2                       |       number of key frames
 811 //      2                       |       key frame number        }               repeats
 812 //      4                       |       key frame offset        }               repeats
 813 //      4                       |       compressed data length
 814 //
 815 void anim_read_header(anim *ptr, CFILE *fp)
 816 {
 817         ptr->width = cfread_short(fp);
 818         // If first 2 bytes are zero, this means we are using a new format, which includes
 819         // a version, and fps values.  This is only done since a version number was not included
 820         // in the original header.
 821
 822         // default
 823         Color_xparent.red = 0;
 824         Color_xparent.green = 255;
 825         Color_xparent.blue = 0;
 826
 827         if ( ptr->width == 0 ) {
 828                 ptr->version = cfread_short(fp);
 829                 ptr->fps = cfread_short(fp);
 830
 831                 // version 2 added a custom transparency color
 832                 if ( ptr->version >= 2 ) {
 833                         cfread(&Color_xparent.red, 1, 1, fp);
 834                         cfread(&Color_xparent.green, 1, 1, fp);
 835                         cfread(&Color_xparent.blue, 1, 1, fp);
 836                 }
 837
 838                 ptr->width = cfread_short(fp);
 839         }
 840         else {
 841                 ptr->version = 0;
 842                 ptr->fps = 30;
 843         }
 844
 845         ptr->height = cfread_short(fp);
 846
 847 #ifndef NDEBUG
 848         // get size of ani compared to power of 2
 849         int r, floor_pow;
 850         r = ptr->height;
 851         floor_pow = 0;
 852
 853         while(r >= 2) {
 854                 r /= 2;
 855                 floor_pow++;
 856         }
 857
 858         int floor_size = (int) pow(2, floor_pow);
 859         int diff = ptr->height - floor_size;
 860         float waste = 100.0f * float((floor_size - diff))/(2.0f *(float)floor_size);
 861
 862         if (diff != 0) {
 863                 if (ptr->height > 16) {
 864                         mprintf(("ANI %s with size %dx%d (%.1f%% wasted)\n", ptr->name, ptr->height, ptr->height, waste));
 865                 }
 866         }
 867 #endif
 868
 869         ptr->total_frames = cfread_short(fp);
 870         ptr->packer_code = cfread_ubyte(fp);
 871         cfread(&ptr->palette, 256, 3, fp);
 872         ptr->num_keys = cfread_short(fp);
 873
 874         // store xparent colors
 875         ptr->xparent_r = Color_xparent.red;
 876         ptr->xparent_g = Color_xparent.green;
 877         ptr->xparent_b = Color_xparent.blue;
 878
 879         if(ptr->total_frames == ptr->num_keys){
 880                 ptr->flags |= ANF_ALL_KEYFRAMES;
 881         }
 882 }
 883
 884 // -----------------------------------------------------------------------------
 885 //      anim_load()
 886 //
 887 // Load an animation.  This stores the compressed data, which instances
 888 // of the animation can reference.  Must be free'ed later with anim_free()
 889 //
 890 // input:       name                            =>              filename of animation
 891 //                              file_mapped             =>              boolean, whether to use memory-mapped file or not.
 892 //                                                                                      Memory-mapped files will page in the animation from disk
 893 //                                                                                      as it is needed, but performance is not as good
 894 //
 895 //      returns:        pointer to anim that is loaded  => sucess
 896 //                              NULL                                                                            =>      failure
 897 //
 898 anim *anim_load(const char *real_filename, int file_mapped)
 899 {
 900         anim                    *ptr;
 901         CFILE                   *fp;
 902         int                     count,idx;
 903         char name[_MAX_PATH];
 904
 905 //      file_mapped = 0;
 906
 907         SDL_assert ( real_filename != NULL );
 908
 909         strcpy( name, real_filename );
 910         char *p = strchr( name, '.' );
 911         if ( p ) {
 912                 *p = 0;
 913         }
 914         strcat( name, ".ani" );
 915
 916         ptr = first_anim;
 917         while (ptr) {
 918                 if (!SDL_strcasecmp(name, ptr->name))
 919                         break;
 920
 921                 ptr = ptr->next;
 922         }
 923
 924         if (!ptr) {
 925                 fp = cfopen(name, "rb");
 926                 if ( !fp )
 927                         return NULL;
 928
 929                 ptr = (anim *) malloc(sizeof(anim));
 930                 SDL_assert(ptr);
 931
 932                 ptr->flags = 0;
 933                 ptr->next = first_anim;
 934                 first_anim = ptr;
 935                 SDL_assert(strlen(name) < _MAX_PATH - 1);
 936                 strcpy(ptr->name, name);
 937                 ptr->instance_count = 0;
 938                 ptr->width = 0;
 939                 ptr->height = 0;
 940                 ptr->total_frames = 0;
 941                 ptr->keys = NULL;
 942                 ptr->ref_count=0;
 943
 944                 anim_read_header(ptr, fp);
 945
 946                 if(ptr->num_keys > 0){
 947                         ptr->keys = (key_frame*)malloc(sizeof(key_frame) * ptr->num_keys);
 948                         SDL_assert(ptr->keys != NULL);
 949                 }
 950
 951                 // store how long the anim should take on playback (in seconds)
 952                 ptr->time = i2fl(ptr->total_frames)/ptr->fps;
 953
 954                 for(idx=0;idx<ptr->num_keys;idx++){
 955                         ptr->keys[idx].frame_num = 0;
 956                         cfread(&ptr->keys[idx].frame_num, 2, 1, fp);
 957                         cfread(&ptr->keys[idx].offset, 4, 1, fp);
 958             ptr->keys[idx].frame_num = INTEL_INT( ptr->keys[idx].frame_num );
 959             ptr->keys[idx].offset = INTEL_INT( ptr->keys[idx].offset );
 960                 }
 961
 962                 /*prev_keyp = &ptr->keys;
 963                 count = ptr->num_keys;
 964                 while (count--) {
 965                         keyp = (key_frame *) malloc(sizeof(key_frame));
 966                         keyp->next = *prev_keyp;
 967                         *prev_keyp = keyp;
 968                         prev_keyp = &keyp->next;
 969
 970                         keyp->frame_num = 0;
 971                         cfread(&keyp->frame_num, 2, 1, fp);
 972                         cfread(&keyp->offset, 4, 1, fp);
 973                 }*/
 974                 cfread(&count, 4, 1, fp);       // size of compressed data
 975         count = INTEL_INT( count );
 976
 977                 ptr->cfile_ptr = NULL;
 978
 979                 if ( file_mapped ) {
 980                         // Try mapping the file to memory
 981                         ptr->flags |= ANF_MEM_MAPPED;
 982                         ptr->cfile_ptr = cfopen(name, "rb", CFILE_MEMORY_MAPPED);
 983                 }
 984
 985                 // couldn't memory-map file... must be in a packfile, so stream manually
 986                 if ( file_mapped && !ptr->cfile_ptr ) {
 987                         ptr->flags &= ~ANF_MEM_MAPPED;
 988                         ptr->flags |= ANF_STREAMED;
 989                         ptr->cfile_ptr = cfopen(name, "rb");
 990                 }
 991
 992                 ptr->cache = NULL;
 993
 994                 // If it opened properly as mem-mapped (or streamed)
 995                 if (ptr->cfile_ptr != NULL)     {
 996                         // VERY IMPORTANT STEP
 997                         // Set the data pointer to the compressed data (which is not at the start of the
 998                         // file).  Use ftell() to find out how far we've already parsed into the file
 999                         //
1000                         int offset;
1001                         offset = cftell(fp);
1002                         ptr->file_offset = offset;
1003                         if ( ptr->flags & ANF_STREAMED ) {
1004                                 ptr->data = NULL;
1005                                 ptr->cache_file_offset = ptr->file_offset;
1006                                 ptr->cache = (ubyte*)malloc(ANI_STREAM_CACHE_SIZE+2);
1007                                 SDL_assert(ptr->cache);
1008                                 cfseek(ptr->cfile_ptr, offset, CF_SEEK_SET);
1009                                 cfread(ptr->cache, ANI_STREAM_CACHE_SIZE, 1, ptr->cfile_ptr);
1010                         } else {
1011                                 ptr->data = (ubyte*)cf_returndata(ptr->cfile_ptr) + offset;
1012                         }
1013                 } else {
1014                         // Not a memory mapped file (or streamed)
1015                         ptr->flags &= ~ANF_MEM_MAPPED;
1016                         ptr->flags &= ~ANF_STREAMED;
1017                         ptr->data = (ubyte *) malloc(count);
1018                         ptr->file_offset = -1;
1019                         cfread(ptr->data, count, 1, fp);
1020                 }
1021
1022                 cfclose(fp);
1023
1024                 // store screen signature, so we can tell if palette changes
1025                 ptr->screen_sig = gr_screen.signature;
1026
1027                 anim_set_palette(ptr);
1028         }
1029
1030         ptr->ref_count++;
1031         return ptr;
1032 }
1033
1034 // ---------------------------------------------------
1035 //      anim_free()
1036 //
1037 // Free an animation that was loaded with anim_load().  All instances
1038 // referencing this animation must be free'ed or get an assert.
1039 //
1040 int anim_free(anim *ptr)
1041 {
1042         SDL_assert ( ptr != NULL );
1043         anim *list, **prev_anim;
1044
1045         list = first_anim;
1046         prev_anim = &first_anim;
1047         while (list && (list != ptr)) {
1048                 prev_anim = &list->next;
1049                 list = list->next;
1050         }
1051
1052         if ( !list )
1053                 return -2;
1054
1055         // only free when ref_count is 0
1056         ptr->ref_count--;
1057         if ( ptr->ref_count > 0 )
1058                 return -1;
1059
1060         // only free if there are no playing instances
1061         if ( ptr->instance_count > 0 )
1062                 return -1;
1063
1064         if(ptr->keys != NULL){
1065                 free(ptr->keys);
1066                 ptr->keys = NULL;
1067         }
1068
1069         if ( ptr->flags & (ANF_MEM_MAPPED|ANF_STREAMED) ) {
1070                 cfclose(ptr->cfile_ptr);
1071                 if ( ptr->cache ) {
1072                         free(ptr->cache);
1073                 }
1074         }
1075         else {
1076                 SDL_assert(ptr->data);
1077                 free(ptr->data);
1078         }
1079
1080         *prev_anim = ptr->next;
1081         free(ptr);
1082         return 0;
1083 }
1084
1085
1086 // ---------------------------------------------------------------------
1087 // anim_playing()
1088 //
1089 // Return if an anim is playing or not.
1090 //
1091 int anim_playing(anim_instance *ai)
1092 {
1093         SDL_assert(ai != NULL);
1094         if ( ai->frame == NULL )
1095                 return 0;
1096         else
1097                 return 1;
1098 }
1099
1100
1101 // ---------------------------------------------------------------------
1102 // anim_level_init()
1103 //
1104 // Called at the beginning of a mission to initialize any mission dependent
1105 // anim data.
1106 //
1107 void anim_level_init()
1108 {
1109 }
1110
1111 // ---------------------------------------------------------------------
1112 // anim_level_close()
1113 //
1114 // Called after the end of a mission to clean up any mission dependent
1115 // anim data.
1116 //
1117 void anim_level_close()
1118 {
1119         anim_release_all_instances();
1120 }
1121
1122 // ---------------------------------------------------
1123 //      anim_write_frames_out()
1124 //
1125 //      Write the frames of a .ani file out to disk as .pcx files.
1126 // Use naming convention: filename0000.pcx, filename0001.pcx etc.
1127 //
1128 // return:              0       =>              success
1129 //                                      -1      =>              failed
1130 //
1131 int anim_write_frames_out(const char *filename)
1132 {
1133         anim                            *source_anim;
1134         anim_instance   *ai;
1135         char                            root_name[256], pcxname[256];
1136         char                            buf[64];
1137         int                             i,j;
1138         ubyte                           **row_data;
1139
1140         strcpy(root_name, filename);
1141         root_name[strlen(filename)-4] = 0;
1142
1143         source_anim = anim_load(filename);
1144         if ( source_anim == NULL )
1145                 return -1;
1146
1147         ai = init_anim_instance(source_anim, 16);
1148
1149         row_data = (ubyte**)malloc((source_anim->height+1) * 4);
1150
1151         for ( i = 0; i < source_anim->total_frames; i++ ) {
1152                 anim_get_next_raw_buffer(ai, 0, 0, 16);
1153                 strcpy(pcxname, root_name);
1154                 sprintf(buf,"%04d",i);
1155                 strcat(pcxname, buf);
1156
1157                 for ( j = 0; j < source_anim->height; j++ ) {
1158                         row_data[j] = &ai->frame[j*source_anim->width];
1159                 }
1160
1161
1162                 pcx_write_bitmap( pcxname,
1163                                                                 source_anim->width,
1164                                                                 source_anim->height,
1165                                                                 row_data,
1166                                                                 source_anim->palette);
1167
1168                 printf(".");
1169
1170         }
1171         printf("\n");
1172         free(row_data);
1173         return 0;
1174 }
1175
1176 // ---------------------------------------------------
1177 //      anim_display_info()
1178 //
1179 //      Display information and statistics about a .ani file.
1180 //      This is called when -i switch is on when running ac.exe
1181 //
1182 void anim_display_info(const char *real_filename)
1183 {
1184         CFILE                           *fp;
1185         anim                            A;
1186         float                           percent;
1187         int                             i, uncompressed, compressed, *key_frame_nums=NULL, tmp;
1188         char filename[MAX_FILENAME_LEN];
1189
1190         strcpy( filename, real_filename );
1191         char *p = strchr( filename, '.' );
1192         if ( p ) {
1193                 *p = 0;
1194         }
1195         strcat( filename, ".ani" );
1196
1197         fp = cfopen(filename, "rb");
1198         if ( !fp ) {
1199                 printf("Fatal error opening %s", filename);
1200                 return;
1201         }
1202
1203         anim_read_header(&A, fp);
1204         // read the keyframe frame nums and offsets
1205         key_frame_nums = (int*)malloc(sizeof(int)*A.num_keys);
1206         SDL_assert(key_frame_nums != NULL);
1207         for ( i = 0; i < A.num_keys; i++ ) {
1208                 key_frame_nums[i] = 0;
1209                 cfread(&key_frame_nums[i], 2, 1, fp);
1210                 cfread(&tmp, 4, 1, fp);
1211 //printf("key frame num: %d,%d\n", key_frame_nums[i],tmp);
1212         }
1213
1214         cfread(&compressed, 4, 1, fp);
1215
1216         uncompressed = A.width * A.height * A.total_frames;     // 8 bits per pixel
1217         percent = i2fl(compressed) / uncompressed * 100.0f;
1218
1219         printf("%% of uncompressed size:    %.0f%%\n", percent);
1220         printf("Width:                     %d\n", A.width);
1221         printf("Height:                    %d\n", A.height);
1222         printf("Total Frames:              %d\n", A.total_frames);
1223
1224 #ifndef NDEBUG
1225         printf("Key Frames:                %d\n", A.num_keys);
1226         if ( A.num_keys > 1 && (A.total_frames != A.num_keys) ) {
1227                 printf("key list: (");
1228                 for ( i = 0; i < A.num_keys; i++ ) {
1229                         if ( i < A.num_keys-1 )
1230                                 printf("%d, ", key_frame_nums[i]);
1231                         else
1232                                 printf("%d)\n", key_frame_nums[i]);
1233                 }
1234         }
1235 #endif
1236
1237         printf("FPS:                       %d\n", A.fps);
1238
1239 #ifndef NDEBUG
1240         printf("Transparent RGB:           (%d,%d,%d)\n", A.xparent_r, A.xparent_g, A.xparent_b);
1241 #endif
1242
1243         printf("ac version:                %d\n", A.version);
1244
1245         if ( key_frame_nums != NULL ) {
1246                 free(key_frame_nums);
1247         }
1248
1249         cfclose(fp);
1250 }
1251
1252 void anim_reverse_direction(anim_instance *ai)
1253 {
1254         int temp;
1255
1256         if(!(ai->parent->flags & ANF_ALL_KEYFRAMES)){
1257                  // you're not allowed to call anim_reverse_direction(...) unless every frame is a keyframe!!!!
1258                  // The God of Delta-RLE demands it be thus.
1259                 Int3();
1260         }
1261
1262         // flip the animation direction
1263         if(ai->direction == ANIM_DIRECT_FORWARD){
1264                 ai->direction = ANIM_DIRECT_REVERSE;
1265         } else if(ai->direction == ANIM_DIRECT_REVERSE){
1266                 ai->direction = ANIM_DIRECT_FORWARD;
1267         }
1268
1269         // flip frame_num and last_frame_num
1270         temp = ai->frame_num;
1271         ai->frame_num = ai->last_frame_num;
1272         ai->last_frame_num = temp;
1273
1274         // flip the start and stop at frames
1275         temp = ai->stop_at;
1276         ai->stop_at = ai->start_at;
1277         ai->start_at = temp;
1278
1279         // make sure to sync up the time correctly
1280         if(ai->direction == ANIM_DIRECT_FORWARD){
1281                 ai->time_elapsed = ((float)ai->frame_num - (float)ai->start_at - 1.0f) / (float)ai->parent->fps;
1282         } else if(ai->direction == ANIM_DIRECT_REVERSE) {
1283                 ai->time_elapsed = ((float)ai->start_at - (float)ai->frame_num - 1.0f) / (float)ai->parent->fps;
1284         }
1285 }
1286
1287 void anim_pause(anim_instance *ai)
1288 {
1289         ai->paused = 1;
1290 }
1291
1292 void anim_unpause(anim_instance *ai)
1293 {
1294         ai->paused = 0;
1295 }
1296
1297 void anim_ignore_next_frametime()
1298 {
1299         Anim_ignore_frametime=1;
1300 }
1301
1302 int anim_instance_is_streamed(anim_instance *ai)
1303 {
1304         SDL_assert(ai);
1305         return ( ai->parent->flags & ANF_STREAMED );
1306 }
1307
1308 unsigned char anim_instance_get_byte(anim_instance *ai, int offset)
1309 {
1310         int absolute_offset;
1311         anim *parent;
1312
1313         SDL_assert(ai);
1314         SDL_assert(ai->parent->cfile_ptr);
1315         SDL_assert(ai->parent->flags & ANF_STREAMED);
1316
1317         parent = ai->parent;
1318         absolute_offset = ai->file_offset + offset;
1319
1320         // maybe in cache?
1321         int cache_offset;
1322         cache_offset = absolute_offset - parent->cache_file_offset;
1323         if ( (cache_offset >= 0) && (cache_offset < ANI_STREAM_CACHE_SIZE) ) {
1324                 return parent->cache[cache_offset];
1325         } else {
1326                 // fill cache
1327                 cfseek(parent->cfile_ptr, absolute_offset, CF_SEEK_SET);
1328                 cfread(parent->cache, ANI_STREAM_CACHE_SIZE, 1, parent->cfile_ptr);
1329                 parent->cache_file_offset = absolute_offset;
1330                 return parent->cache[0];
1331         }
1332 }
1333