main/lighting.c

   1 /*
   2 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
   3 SOFTWARE CORPORATION ("PARALLAX").  PARALLAX, IN DISTRIBUTING THE CODE TO
   4 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
   5 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
   6 IN USING, DISPLAYING,  AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
   7 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
   8 FREE PURPOSES.  IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
   9 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES.  THE END-USER UNDERSTANDS
  10 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
  11 COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
  12 */
  13
  14
  15 #ifdef RCS
  16 static char rcsid[] = "$Id: lighting.c,v 1.1.1.1 2001-01-19 03:30:00 bradleyb Exp $";
  17 #endif
  18
  19 #include <conf.h>
  20 #include <stdio.h>
  21 #include <string.h>     // for memset()
  22
  23 #include "fix.h"
  24 #include "vecmat.h"
  25 #include "gr.h"
  26 #include "inferno.h"
  27 #include "segment.h"
  28 #include "error.h"
  29 #include "mono.h"
  30 #include "render.h"
  31 #include "game.h"
  32 #include "vclip.h"
  33 #include "lighting.h"
  34 #include "3d.h"
  35 #include "laser.h"
  36 #include "timer.h"
  37 #include "player.h"
  38 #include "weapon.h"
  39 #include "powerup.h"
  40 #include "fvi.h"
  41 #include "robot.h"
  42 #include "multi.h"
  43
  44 int     Do_dynamic_light=1;
  45 //int   Use_fvi_lighting = 0;
  46
  47 fix     Dynamic_light[MAX_VERTICES];
  48
  49 #define LIGHTING_CACHE_SIZE     4096    //      Must be power of 2!
  50 #define LIGHTING_FRAME_DELTA    256     //      Recompute cache value every 8 frames.
  51 #define LIGHTING_CACHE_SHIFT    8
  52
  53 int     Lighting_frame_delta = 1;
  54
  55 int     Lighting_cache[LIGHTING_CACHE_SIZE];
  56
  57 int Cache_hits=0, Cache_lookups=1;
  58
  59 //      Return true if we think vertex vertnum is visible from segment segnum.
  60 //      If some amount of time has gone by, then recompute, else use cached value.
  61 int lighting_cache_visible(int vertnum, int segnum, int objnum, vms_vector *obj_pos, int obj_seg, vms_vector *vertpos)
  62 {
  63         int     cache_val, cache_frame, cache_vis;
  64
  65         cache_val = Lighting_cache[((segnum << LIGHTING_CACHE_SHIFT) ^ vertnum) & (LIGHTING_CACHE_SIZE-1)];
  66
  67         cache_frame = cache_val >> 1;
  68         cache_vis = cache_val & 1;
  69
  70 //mprintf((0, "%i %i %5i %i ", vertnum, segnum, cache_frame, cache_vis));
  71
  72 Cache_lookups++;
  73         if ((cache_frame == 0) || (cache_frame + Lighting_frame_delta <= FrameCount)) {
  74                 int                     apply_light=0;
  75                 fvi_query       fq;
  76                 fvi_info                hit_data;
  77                 int                     segnum, hit_type;
  78
  79                 #ifndef NDEBUG
  80                 segnum = find_point_seg(obj_pos, obj_seg);
  81                 if (segnum == -1) {
  82                         Int3();         //      Obj_pos is not in obj_seg!
  83                         return 0;               //      Done processing this object.
  84                 }
  85                 #endif
  86
  87                 fq.p0                                           = obj_pos;
  88                 fq.startseg                             = obj_seg;
  89                 fq.p1                                           = vertpos;
  90                 fq.rad                                  = 0;
  91                 fq.thisobjnum                   = objnum;
  92                 fq.ignore_obj_list      = NULL;
  93                 fq.flags                                        = FQ_TRANSWALL;
  94
  95                 hit_type = find_vector_intersection(&fq, &hit_data);
  96
  97                 // Hit_pos = Hit_data.hit_pnt;
  98                 // Hit_seg = Hit_data.hit_seg;
  99
 100                 if (hit_type == HIT_OBJECT)
 101                         Int3(); //      Hey, we're not supposed to be checking objects!
 102
 103                 if (hit_type == HIT_NONE)
 104                         apply_light = 1;
 105                 else if (hit_type == HIT_WALL) {
 106                         fix     dist_dist;
 107                         dist_dist = vm_vec_dist_quick(&hit_data.hit_pnt, obj_pos);
 108                         if (dist_dist < F1_0/4) {
 109                                 apply_light = 1;
 110                                 // -- Int3();   //      Curious, did fvi detect intersection with wall containing vertex?
 111                         }
 112                 }
 113                 Lighting_cache[((segnum << LIGHTING_CACHE_SHIFT) ^ vertnum) & (LIGHTING_CACHE_SIZE-1)] = apply_light + (FrameCount << 1);
 114 //mprintf((0, "%i\n", apply_light));
 115                 return apply_light;
 116         } else {
 117 //mprintf((0, "\n"));
 118 Cache_hits++;
 119                 return cache_vis;
 120         }
 121 }
 122
 123 #define HEADLIGHT_CONE_DOT      (F1_0*9/10)
 124 #define HEADLIGHT_SCALE         (F1_0*10)
 125
 126 // ----------------------------------------------------------------------------------------------
 127 void apply_light(fix obj_intensity, int obj_seg, vms_vector *obj_pos, int n_render_vertices, short *render_vertices, int objnum)
 128 {
 129         int     vv;
 130
 131         if (obj_intensity) {
 132                 fix     obji_64 = obj_intensity*64;
 133
 134                 // for pretty dim sources, only process vertices in object's own segment.
 135                 //      12/04/95, MK, markers only cast light in own segment.
 136                 if ((abs(obji_64) <= F1_0*8) || (Objects[objnum].type == OBJ_MARKER)) {
 137                         short *vp = Segments[obj_seg].verts;
 138
 139                         for (vv=0; vv<MAX_VERTICES_PER_SEGMENT; vv++) {
 140                                 int                     vertnum;
 141                                 vms_vector      *vertpos;
 142                                 fix                     dist;
 143
 144                                 vertnum = vp[vv];
 145                                 if ((vertnum ^ FrameCount) & 1) {
 146                                         vertpos = &Vertices[vertnum];
 147                                         dist = vm_vec_dist_quick(obj_pos, vertpos);
 148                                         dist = fixmul(dist/4, dist/4);
 149                                         if (dist < abs(obji_64)) {
 150                                                 if (dist < MIN_LIGHT_DIST)
 151                                                         dist = MIN_LIGHT_DIST;
 152
 153                                                 Dynamic_light[vertnum] += fixdiv(obj_intensity, dist);
 154                                         }
 155                                 }
 156                         }
 157                 } else {
 158                         int     headlight_shift = 0;
 159                         fix     max_headlight_dist = F1_0*200;
 160
 161                         if (Objects[objnum].type == OBJ_PLAYER)
 162                                 if (Players[Objects[objnum].id].flags & PLAYER_FLAGS_HEADLIGHT_ON) {
 163                                         headlight_shift = 3;
 164                                         if (Objects[objnum].id != Player_num) {
 165                                                 vms_vector      tvec;
 166                                                 fvi_query       fq;
 167                                                 fvi_info                hit_data;
 168                                                 int                     fate;
 169
 170                                                 vm_vec_scale_add(&tvec, &Objects[objnum].pos, &Objects[objnum].orient.fvec, F1_0*200);
 171
 172                                                 fq.startseg                             = Objects[objnum].segnum;
 173                                                 fq.p0                                           = &Objects[objnum].pos;
 174                                                 fq.p1                                           = &tvec;
 175                                                 fq.rad                                  = 0;
 176                                                 fq.thisobjnum                   = objnum;
 177                                                 fq.ignore_obj_list      = NULL;
 178                                                 fq.flags                                        = FQ_TRANSWALL;
 179
 180                                                 fate = find_vector_intersection(&fq, &hit_data);
 181                                                 if (fate != HIT_NONE)
 182                                                         max_headlight_dist = vm_vec_mag_quick(vm_vec_sub(&tvec, &hit_data.hit_pnt, &Objects[objnum].pos)) + F1_0*4;
 183                                         }
 184                                 }
 185                         // -- for (vv=FrameCount&1; vv<n_render_vertices; vv+=2) {
 186                         for (vv=0; vv<n_render_vertices; vv++) {
 187                                 int                     vertnum;
 188                                 vms_vector      *vertpos;
 189                                 fix                     dist;
 190                                 int                     apply_light;
 191
 192                                 vertnum = render_vertices[vv];
 193                                 if ((vertnum ^ FrameCount) & 1) {
 194                                         vertpos = &Vertices[vertnum];
 195                                         dist = vm_vec_dist_quick(obj_pos, vertpos);
 196                                         apply_light = 0;
 197
 198                                         if ((dist >> headlight_shift) < abs(obji_64)) {
 199
 200                                                 if (dist < MIN_LIGHT_DIST)
 201                                                         dist = MIN_LIGHT_DIST;
 202
 203                                                 //if (Use_fvi_lighting) {
 204                                                 //      if (lighting_cache_visible(vertnum, obj_seg, objnum, obj_pos, obj_seg, vertpos)) {
 205                                                 //              apply_light = 1;
 206                                                 //      }
 207                                                 //} else
 208                                                         apply_light = 1;
 209
 210                                                 if (apply_light) {
 211                                                         if (headlight_shift) {
 212                                                                 fix                     dot;
 213                                                                 vms_vector      vec_to_point;
 214
 215                                                                 vm_vec_sub(&vec_to_point, vertpos, obj_pos);
 216                                                                 vm_vec_normalize_quick(&vec_to_point);          //      MK, Optimization note: You compute distance about 15 lines up, this is partially redundant
 217                                                                 dot = vm_vec_dot(&vec_to_point, &Objects[objnum].orient.fvec);
 218                                                                 if (dot < F1_0/2)
 219                                                                         Dynamic_light[vertnum] += fixdiv(obj_intensity, fixmul(HEADLIGHT_SCALE, dist)); //      Do the normal thing, but darken around headlight.
 220                                                                 else {
 221                                                                         if (Game_mode & GM_MULTI) {
 222                                                                                 if (dist < max_headlight_dist)
 223                                                                                         Dynamic_light[vertnum] += fixmul(fixmul(dot, dot), obj_intensity)/8;
 224                                                                         } else
 225                                                                                 Dynamic_light[vertnum] += fixmul(fixmul(dot, dot), obj_intensity)/8;
 226                                                                 }
 227                                                         } else
 228                                                                 Dynamic_light[vertnum] += fixdiv(obj_intensity, dist);
 229                                                 }
 230                                         }
 231                                 }
 232                         }
 233                 }
 234         }
 235 }
 236
 237 #define FLASH_LEN_FIXED_SECONDS (F1_0/3)
 238 #define FLASH_SCALE                                     (3*F1_0/FLASH_LEN_FIXED_SECONDS)
 239
 240 // ----------------------------------------------------------------------------------------------
 241 void cast_muzzle_flash_light(int n_render_vertices, short *render_vertices)
 242 {
 243         fix current_time;
 244         int     i;
 245         short   time_since_flash;
 246
 247         current_time = timer_get_fixed_seconds();
 248
 249         for (i=0; i<MUZZLE_QUEUE_MAX; i++) {
 250                 if (Muzzle_data[i].create_time) {
 251                         time_since_flash = current_time - Muzzle_data[i].create_time;
 252                         if (time_since_flash < FLASH_LEN_FIXED_SECONDS)
 253                                 apply_light((FLASH_LEN_FIXED_SECONDS - time_since_flash) * FLASH_SCALE, Muzzle_data[i].segnum, &Muzzle_data[i].pos, n_render_vertices, render_vertices, -1);
 254                         else
 255                                 Muzzle_data[i].create_time = 0;         // turn off this muzzle flash
 256                 }
 257         }
 258 }
 259
 260 //      Translation table to make flares flicker at different rates
 261 fix     Obj_light_xlate[16] =
 262         {0x1234, 0x3321, 0x2468, 0x1735,
 263          0x0123, 0x19af, 0x3f03, 0x232a,
 264          0x2123, 0x39af, 0x0f03, 0x132a,
 265          0x3123, 0x29af, 0x1f03, 0x032a};
 266
 267 //      Flag array of objects lit last frame.  Guaranteed to process this frame if lit last frame.
 268 byte    Lighting_objects[MAX_OBJECTS];
 269
 270 #define MAX_HEADLIGHTS  8
 271 object  *Headlights[MAX_HEADLIGHTS];
 272 int             Num_headlights;
 273
 274 // ---------------------------------------------------------
 275 fix compute_light_intensity(int objnum)
 276 {
 277         object          *obj = &Objects[objnum];
 278         int                     objtype = obj->type;
 279    fix hoardlight,s;
 280
 281         switch (objtype) {
 282                 case OBJ_PLAYER:
 283                          if (Players[obj->id].flags & PLAYER_FLAGS_HEADLIGHT_ON) {
 284                                 if (Num_headlights < MAX_HEADLIGHTS)
 285                                         Headlights[Num_headlights++] = obj;
 286                                 return HEADLIGHT_SCALE;
 287                          } else if ((Game_mode & GM_HOARD) && Players[obj->id].secondary_ammo[PROXIMITY_INDEX]) {
 288
 289                    // If hoard game and player, add extra light based on how many orbs you have
 290                         // Pulse as well.
 291
 292                            hoardlight=i2f(Players[obj->id].secondary_ammo[PROXIMITY_INDEX])/2; //i2f(12));
 293                                 hoardlight++;
 294                       fix_sincos ((GameTime/2) & 0xFFFF,&s,NULL); // probably a bad way to do it
 295                            s+=F1_0;
 296                                 s>>=1;
 297                            hoardlight=fixmul (s,hoardlight);
 298                  //     mprintf ((0,"Hoardlight is %f!\n",f2fl(hoardlight)));
 299                       return (hoardlight);
 300                           }
 301                         else
 302                                 return max(vm_vec_mag_quick(&obj->mtype.phys_info.thrust)/4, F1_0*2) + F1_0/2;
 303                         break;
 304                 case OBJ_FIREBALL:
 305                         if (obj->id != 0xff) {
 306                                 if (obj->lifeleft < F1_0*4)
 307                                         return fixmul(fixdiv(obj->lifeleft, Vclip[obj->id].play_time), Vclip[obj->id].light_value);
 308                                 else
 309                                         return Vclip[obj->id].light_value;
 310                         } else
 311                                  return 0;
 312                         break;
 313                 case OBJ_ROBOT:
 314                         return F1_0*Robot_info[obj->id].lightcast;
 315                         break;
 316                 case OBJ_WEAPON: {
 317                         fix tval = Weapon_info[obj->id].light;
 318                         if (Game_mode & GM_MULTI)
 319                                 if (obj->id == OMEGA_ID)
 320                                         if (d_rand() > 8192)
 321                                                 return 0;               //      3/4 of time, omega blobs will cast 0 light!
 322
 323                         if (obj->id == FLARE_ID )
 324                                 return 2* (min(tval, obj->lifeleft) + ((GameTime ^ Obj_light_xlate[objnum&0x0f]) & 0x3fff));
 325                         else
 326                                 return tval;
 327                 }
 328
 329                 case OBJ_MARKER: {
 330                         fix     lightval = obj->lifeleft;
 331
 332                         lightval &= 0xffff;
 333
 334                         lightval = 8 * abs(F1_0/2 - lightval);
 335
 336                         if (obj->lifeleft < F1_0*1000)
 337                                 obj->lifeleft += F1_0;  //      Make sure this object doesn't go out.
 338
 339                         return lightval;
 340                 }
 341
 342                 case OBJ_POWERUP:
 343                         return Powerup_info[obj->id].light;
 344                         break;
 345                 case OBJ_DEBRIS:
 346                         return F1_0/4;
 347                         break;
 348                 case OBJ_LIGHT:
 349                         return obj->ctype.light_info.intensity;
 350                         break;
 351                 default:
 352                         return 0;
 353                         break;
 354         }
 355 }
 356
 357 // ----------------------------------------------------------------------------------------------
 358 void set_dynamic_light(void)
 359 {
 360         int     vv;
 361         int     objnum;
 362         int     n_render_vertices;
 363         short   render_vertices[MAX_VERTICES];
 364         byte    render_vertex_flags[MAX_VERTICES];
 365         int     render_seg,segnum, v;
 366         byte    new_lighting_objects[MAX_OBJECTS];
 367
 368         Num_headlights = 0;
 369
 370         if (!Do_dynamic_light)
 371                 return;
 372
 373 //if (Use_fvi_lighting)
 374 //      mprintf((0, "hits = %8i, misses = %8i, lookups = %8i, hit ratio = %7.4f\n", Cache_hits, Cache_lookups - Cache_hits, Cache_lookups, (float) Cache_hits / Cache_lookups));
 375
 376         memset(render_vertex_flags, 0, Highest_vertex_index+1);
 377
 378         //      Create list of vertices that need to be looked at for setting of ambient light.
 379         n_render_vertices = 0;
 380         for (render_seg=0; render_seg<N_render_segs; render_seg++) {
 381                 segnum = Render_list[render_seg];
 382                 if (segnum != -1) {
 383                         short   *vp = Segments[segnum].verts;
 384                         for (v=0; v<MAX_VERTICES_PER_SEGMENT; v++) {
 385                                 int     vnum = vp[v];
 386                                 if (vnum<0 || vnum>Highest_vertex_index) {
 387                                         Int3();         //invalid vertex number
 388                                         continue;       //ignore it, and go on to next one
 389                                 }
 390                                 if (!render_vertex_flags[vnum]) {
 391                                         render_vertex_flags[vnum] = 1;
 392                                         render_vertices[n_render_vertices++] = vnum;
 393                                 }
 394                                 //--old way-- for (s=0; s<n_render_vertices; s++)
 395                                 //--old way--   if (render_vertices[s] == vnum)
 396                                 //--old way--           break;
 397                                 //--old way-- if (s == n_render_vertices)
 398                                 //--old way--   render_vertices[n_render_vertices++] = vnum;
 399                         }
 400                 }
 401         }
 402
 403         // -- for (vertnum=FrameCount&1; vertnum<n_render_vertices; vertnum+=2) {
 404         for (vv=0; vv<n_render_vertices; vv++) {
 405                 int     vertnum;
 406
 407                 vertnum = render_vertices[vv];
 408                 Assert(vertnum >= 0 && vertnum <= Highest_vertex_index);
 409                 if ((vertnum ^ FrameCount) & 1)
 410                         Dynamic_light[vertnum] = 0;
 411         }
 412
 413         cast_muzzle_flash_light(n_render_vertices, render_vertices);
 414
 415         for (objnum=0; objnum<=Highest_object_index; objnum++)
 416                 new_lighting_objects[objnum] = 0;
 417
 418         //      July 5, 1995: New faster dynamic lighting code.  About 5% faster on the PC (un-optimized).
 419         //      Only objects which are in rendered segments cast dynamic light.  We might wad6 to extend this
 420         //      one or two segments if we notice light changing as objects go offscreen.  I couldn't see any
 421         //      serious visual degradation.  In fact, I could see no humorous degradation, either. --MK
 422         for (render_seg=0; render_seg<N_render_segs; render_seg++) {
 423                 int     segnum = Render_list[render_seg];
 424
 425                 objnum = Segments[segnum].objects;
 426
 427                 while (objnum != -1) {
 428                         object          *obj = &Objects[objnum];
 429                         vms_vector      *objpos = &obj->pos;
 430                         fix                     obj_intensity;
 431
 432                         obj_intensity = compute_light_intensity(objnum);
 433
 434                         if (obj_intensity) {
 435                                 apply_light(obj_intensity, obj->segnum, objpos, n_render_vertices, render_vertices, obj-Objects);
 436                                 new_lighting_objects[objnum] = 1;
 437                         }
 438
 439                         objnum = obj->next;
 440                 }
 441         }
 442
 443         //      Now, process all lights from last frame which haven't been processed this frame.
 444         for (objnum=0; objnum<=Highest_object_index; objnum++) {
 445                 //      In multiplayer games, process even unprocessed objects every 4th frame, else don't know about player sneaking up.
 446                 if ((Lighting_objects[objnum]) || ((Game_mode & GM_MULTI) && (((objnum ^ FrameCount) & 3) == 0))) {
 447                         if (!new_lighting_objects[objnum]) {
 448                                 //      Lighted last frame, but not this frame.  Get intensity...
 449                                 object          *obj = &Objects[objnum];
 450                                 vms_vector      *objpos = &obj->pos;
 451                                 fix                     obj_intensity;
 452
 453                                 obj_intensity = compute_light_intensity(objnum);
 454
 455                                 if (obj_intensity) {
 456                                         apply_light(obj_intensity, obj->segnum, objpos, n_render_vertices, render_vertices, objnum);
 457                                         Lighting_objects[objnum] = 1;
 458                                 } else
 459                                         Lighting_objects[objnum] = 0;
 460                         }
 461                 } else {
 462                         //      Not lighted last frame, so we don't need to light it.  (Already lit if casting light this frame.)
 463                         //      But copy value from new_lighting_objects to update Lighting_objects array.
 464                         Lighting_objects[objnum] = new_lighting_objects[objnum];
 465                 }
 466         }
 467 }
 468
 469 // ---------------------------------------------------------
 470
 471 void toggle_headlight_active()
 472 {
 473         if (Players[Player_num].flags & PLAYER_FLAGS_HEADLIGHT) {
 474                 Players[Player_num].flags ^= PLAYER_FLAGS_HEADLIGHT_ON;
 475 #ifdef NETWORK
 476                 if (Game_mode & GM_MULTI)
 477                         multi_send_flags(Player_num);
 478 #endif
 479         }
 480 }
 481
 482 #define HEADLIGHT_BOOST_SCALE 8         //how much to scale light when have headlight boost
 483
 484 fix     Beam_brightness = (F1_0/2);     //global saying how bright the light beam is
 485
 486 #define MAX_DIST_LOG    6                                                       //log(MAX_DIST-expressed-as-integer)
 487 #define MAX_DIST                (f1_0<<MAX_DIST_LOG)    //no light beyond this dist
 488
 489 fix compute_headlight_light_on_object(object *objp)
 490 {
 491         int     i;
 492         fix     light;
 493
 494         //      Let's just illuminate players and robots for speed reasons, ok?
 495         if ((objp->type != OBJ_ROBOT) && (objp->type    != OBJ_PLAYER))
 496                 return 0;
 497
 498         light = 0;
 499
 500         for (i=0; i<Num_headlights; i++) {
 501                 fix                     dot, dist;
 502                 vms_vector      vec_to_obj;
 503                 object          *light_objp;
 504
 505                 light_objp = Headlights[i];
 506
 507                 vm_vec_sub(&vec_to_obj, &objp->pos, &light_objp->pos);
 508                 dist = vm_vec_normalize_quick(&vec_to_obj);
 509                 if (dist > 0) {
 510                         dot = vm_vec_dot(&light_objp->orient.fvec, &vec_to_obj);
 511
 512                         if (dot < F1_0/2)
 513                                 light += fixdiv(HEADLIGHT_SCALE, fixmul(HEADLIGHT_SCALE, dist));        //      Do the normal thing, but darken around headlight.
 514                         else
 515                                 light += fixmul(fixmul(dot, dot), HEADLIGHT_SCALE)/8;
 516                 }
 517         }
 518
 519         return light;
 520 }
 521
 522
 523 // -- Unused -- //Compute the lighting from the headlight for a given vertex on a face.
 524 // -- Unused -- //Takes:
 525 // -- Unused -- //  point - the 3d coords of the point
 526 // -- Unused -- //  face_light - a scale factor derived from the surface normal of the face
 527 // -- Unused -- //If no surface normal effect is wanted, pass F1_0 for face_light
 528 // -- Unused -- fix compute_headlight_light(vms_vector *point,fix face_light)
 529 // -- Unused -- {
 530 // -- Unused --         fix light;
 531 // -- Unused --         int use_beam = 0;               //flag for beam effect
 532 // -- Unused --
 533 // -- Unused --         light = Beam_brightness;
 534 // -- Unused --
 535 // -- Unused --         if ((Players[Player_num].flags & PLAYER_FLAGS_HEADLIGHT) && (Players[Player_num].flags & PLAYER_FLAGS_HEADLIGHT_ON) && Viewer==&Objects[Players[Player_num].objnum] && Players[Player_num].energy > 0) {
 536 // -- Unused --                 light *= HEADLIGHT_BOOST_SCALE;
 537 // -- Unused --                 use_beam = 1;   //give us beam effect
 538 // -- Unused --         }
 539 // -- Unused --
 540 // -- Unused --         if (light) {                            //if no beam, don't bother with the rest of this
 541 // -- Unused --                 fix point_dist;
 542 // -- Unused --
 543 // -- Unused --                 point_dist = vm_vec_mag_quick(point);
 544 // -- Unused --
 545 // -- Unused --                 if (point_dist >= MAX_DIST)
 546 // -- Unused --
 547 // -- Unused --                         light = 0;
 548 // -- Unused --
 549 // -- Unused --                 else {
 550 // -- Unused --                         fix dist_scale,face_scale;
 551 // -- Unused --
 552 // -- Unused --                         dist_scale = (MAX_DIST - point_dist) >> MAX_DIST_LOG;
 553 // -- Unused --                         light = fixmul(light,dist_scale);
 554 // -- Unused --
 555 // -- Unused --                         if (face_light < 0)
 556 // -- Unused --                                 face_light = 0;
 557 // -- Unused --
 558 // -- Unused --                         face_scale = f1_0/4 + face_light/2;
 559 // -- Unused --                         light = fixmul(light,face_scale);
 560 // -- Unused --
 561 // -- Unused --                         if (use_beam) {
 562 // -- Unused --                                 fix beam_scale;
 563 // -- Unused --
 564 // -- Unused --                                 if (face_light > f1_0*3/4 && point->z > i2f(12)) {
 565 // -- Unused --                                         beam_scale = fixdiv(point->z,point_dist);
 566 // -- Unused --                                         beam_scale = fixmul(beam_scale,beam_scale);     //square it
 567 // -- Unused --                                         light = fixmul(light,beam_scale);
 568 // -- Unused --                                 }
 569 // -- Unused --                         }
 570 // -- Unused --                 }
 571 // -- Unused --         }
 572 // -- Unused --
 573 // -- Unused --         return light;
 574 // -- Unused -- }
 575
 576 //compute the average dynamic light in a segment.  Takes the segment number
 577 fix compute_seg_dynamic_light(int segnum)
 578 {
 579         fix sum;
 580         segment *seg;
 581         short *verts;
 582
 583         seg = &Segments[segnum];
 584
 585         verts = seg->verts;
 586         sum = 0;
 587
 588         sum += Dynamic_light[*verts++];
 589         sum += Dynamic_light[*verts++];
 590         sum += Dynamic_light[*verts++];
 591         sum += Dynamic_light[*verts++];
 592         sum += Dynamic_light[*verts++];
 593         sum += Dynamic_light[*verts++];
 594         sum += Dynamic_light[*verts++];
 595         sum += Dynamic_light[*verts];
 596
 597         return sum >> 3;
 598
 599 }
 600
 601 fix object_light[MAX_OBJECTS];
 602 int object_sig[MAX_OBJECTS];
 603 object *old_viewer;
 604 int reset_lighting_hack;
 605
 606 #define LIGHT_RATE i2f(4)               //how fast the light ramps up
 607
 608 void start_lighting_frame(object *viewer)
 609 {
 610         reset_lighting_hack = (viewer != old_viewer);
 611
 612         old_viewer = viewer;
 613 }
 614
 615 //compute the lighting for an object.  Takes a pointer to the object,
 616 //and possibly a rotated 3d point.  If the point isn't specified, the
 617 //object's center point is rotated.
 618 fix compute_object_light(object *obj,vms_vector *rotated_pnt)
 619 {
 620         fix light;
 621         g3s_point objpnt;
 622         int objnum = obj-Objects;
 623
 624         if (!rotated_pnt) {
 625                 g3_rotate_point(&objpnt,&obj->pos);
 626                 rotated_pnt = &objpnt.p3_vec;
 627         }
 628
 629         //First, get static light for this segment
 630
 631         light = Segment2s[obj->segnum].static_light;
 632
 633         //return light;
 634
 635
 636         //Now, maybe return different value to smooth transitions
 637
 638         if (!reset_lighting_hack && object_sig[objnum] == obj->signature) {
 639                 fix delta_light,frame_delta;
 640
 641                 delta_light = light - object_light[objnum];
 642
 643                 frame_delta = fixmul(LIGHT_RATE,FrameTime);
 644
 645                 if (abs(delta_light) <= frame_delta)
 646
 647                         object_light[objnum] = light;           //we've hit the goal
 648
 649                 else
 650
 651                         if (delta_light < 0)
 652                                 light = object_light[objnum] -= frame_delta;
 653                         else
 654                                 light = object_light[objnum] += frame_delta;
 655
 656         }
 657         else {          //new object, initialize
 658
 659                 object_sig[objnum] = obj->signature;
 660                 object_light[objnum] = light;
 661         }
 662
 663
 664
 665         //Next, add in headlight on this object
 666
 667         // -- Matt code: light += compute_headlight_light(rotated_pnt,f1_0);
 668         light += compute_headlight_light_on_object(obj);
 669
 670         //Finally, add in dynamic light for this segment
 671
 672         light += compute_seg_dynamic_light(obj->segnum);
 673
 674
 675         return light;
 676 }
 677
 678