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 #ifdef HAVE_CONFIG_H
  15 #include <conf.h>
  16 #endif
  17
  18 #ifdef RCS
  19 static char rcsid[] = "$Id: lighting.c,v 1.3 2001-01-31 15:17:54 bradleyb Exp $";
  20 #endif
  21
  22 #include <stdio.h>
  23 #include <string.h>     // for memset()
  24
  25 #include "fix.h"
  26 #include "vecmat.h"
  27 #include "gr.h"
  28 #include "inferno.h"
  29 #include "segment.h"
  30 #include "error.h"
  31 #include "mono.h"
  32 #include "render.h"
  33 #include "game.h"
  34 #include "vclip.h"
  35 #include "lighting.h"
  36 #include "3d.h"
  37 #include "laser.h"
  38 #include "timer.h"
  39 #include "player.h"
  40 #include "weapon.h"
  41 #include "powerup.h"
  42 #include "fvi.h"
  43 #include "robot.h"
  44 #include "multi.h"
  45
  46 int     Do_dynamic_light=1;
  47 //int   Use_fvi_lighting = 0;
  48
  49 fix     Dynamic_light[MAX_VERTICES];
  50
  51 #define LIGHTING_CACHE_SIZE     4096    //      Must be power of 2!
  52 #define LIGHTING_FRAME_DELTA    256     //      Recompute cache value every 8 frames.
  53 #define LIGHTING_CACHE_SHIFT    8
  54
  55 int     Lighting_frame_delta = 1;
  56
  57 int     Lighting_cache[LIGHTING_CACHE_SIZE];
  58
  59 int Cache_hits=0, Cache_lookups=1;
  60
  61 //      Return true if we think vertex vertnum is visible from segment segnum.
  62 //      If some amount of time has gone by, then recompute, else use cached value.
  63 int lighting_cache_visible(int vertnum, int segnum, int objnum, vms_vector *obj_pos, int obj_seg, vms_vector *vertpos)
  64 {
  65         int     cache_val, cache_frame, cache_vis;
  66
  67         cache_val = Lighting_cache[((segnum << LIGHTING_CACHE_SHIFT) ^ vertnum) & (LIGHTING_CACHE_SIZE-1)];
  68
  69         cache_frame = cache_val >> 1;
  70         cache_vis = cache_val & 1;
  71
  72 //mprintf((0, "%i %i %5i %i ", vertnum, segnum, cache_frame, cache_vis));
  73
  74 Cache_lookups++;
  75         if ((cache_frame == 0) || (cache_frame + Lighting_frame_delta <= FrameCount)) {
  76                 int                     apply_light=0;
  77                 fvi_query       fq;
  78                 fvi_info                hit_data;
  79                 int                     segnum, hit_type;
  80
  81                 segnum = -1;
  82
  83                 #ifndef NDEBUG
  84                 segnum = find_point_seg(obj_pos, obj_seg);
  85                 if (segnum == -1) {
  86                         Int3();         //      Obj_pos is not in obj_seg!
  87                         return 0;               //      Done processing this object.
  88                 }
  89                 #endif
  90
  91                 fq.p0                                           = obj_pos;
  92                 fq.startseg                             = obj_seg;
  93                 fq.p1                                           = vertpos;
  94                 fq.rad                                  = 0;
  95                 fq.thisobjnum                   = objnum;
  96                 fq.ignore_obj_list      = NULL;
  97                 fq.flags                                        = FQ_TRANSWALL;
  98
  99                 hit_type = find_vector_intersection(&fq, &hit_data);
 100
 101                 // Hit_pos = Hit_data.hit_pnt;
 102                 // Hit_seg = Hit_data.hit_seg;
 103
 104                 if (hit_type == HIT_OBJECT)
 105                         Int3(); //      Hey, we're not supposed to be checking objects!
 106
 107                 if (hit_type == HIT_NONE)
 108                         apply_light = 1;
 109                 else if (hit_type == HIT_WALL) {
 110                         fix     dist_dist;
 111                         dist_dist = vm_vec_dist_quick(&hit_data.hit_pnt, obj_pos);
 112                         if (dist_dist < F1_0/4) {
 113                                 apply_light = 1;
 114                                 // -- Int3();   //      Curious, did fvi detect intersection with wall containing vertex?
 115                         }
 116                 }
 117                 Lighting_cache[((segnum << LIGHTING_CACHE_SHIFT) ^ vertnum) & (LIGHTING_CACHE_SIZE-1)] = apply_light + (FrameCount << 1);
 118 //mprintf((0, "%i\n", apply_light));
 119                 return apply_light;
 120         } else {
 121 //mprintf((0, "\n"));
 122 Cache_hits++;
 123                 return cache_vis;
 124         }
 125 }
 126
 127 #define HEADLIGHT_CONE_DOT      (F1_0*9/10)
 128 #define HEADLIGHT_SCALE         (F1_0*10)
 129
 130 // ----------------------------------------------------------------------------------------------
 131 void apply_light(fix obj_intensity, int obj_seg, vms_vector *obj_pos, int n_render_vertices, short *render_vertices, int objnum)
 132 {
 133         int     vv;
 134
 135         if (obj_intensity) {
 136                 fix     obji_64 = obj_intensity*64;
 137
 138                 // for pretty dim sources, only process vertices in object's own segment.
 139                 //      12/04/95, MK, markers only cast light in own segment.
 140                 if ((abs(obji_64) <= F1_0*8) || (Objects[objnum].type == OBJ_MARKER)) {
 141                         short *vp = Segments[obj_seg].verts;
 142
 143                         for (vv=0; vv<MAX_VERTICES_PER_SEGMENT; vv++) {
 144                                 int                     vertnum;
 145                                 vms_vector      *vertpos;
 146                                 fix                     dist;
 147
 148                                 vertnum = vp[vv];
 149                                 if ((vertnum ^ FrameCount) & 1) {
 150                                         vertpos = &Vertices[vertnum];
 151                                         dist = vm_vec_dist_quick(obj_pos, vertpos);
 152                                         dist = fixmul(dist/4, dist/4);
 153                                         if (dist < abs(obji_64)) {
 154                                                 if (dist < MIN_LIGHT_DIST)
 155                                                         dist = MIN_LIGHT_DIST;
 156
 157                                                 Dynamic_light[vertnum] += fixdiv(obj_intensity, dist);
 158                                         }
 159                                 }
 160                         }
 161                 } else {
 162                         int     headlight_shift = 0;
 163                         fix     max_headlight_dist = F1_0*200;
 164
 165                         if (Objects[objnum].type == OBJ_PLAYER)
 166                                 if (Players[Objects[objnum].id].flags & PLAYER_FLAGS_HEADLIGHT_ON) {
 167                                         headlight_shift = 3;
 168                                         if (Objects[objnum].id != Player_num) {
 169                                                 vms_vector      tvec;
 170                                                 fvi_query       fq;
 171                                                 fvi_info                hit_data;
 172                                                 int                     fate;
 173
 174                                                 vm_vec_scale_add(&tvec, &Objects[objnum].pos, &Objects[objnum].orient.fvec, F1_0*200);
 175
 176                                                 fq.startseg                             = Objects[objnum].segnum;
 177                                                 fq.p0                                           = &Objects[objnum].pos;
 178                                                 fq.p1                                           = &tvec;
 179                                                 fq.rad                                  = 0;
 180                                                 fq.thisobjnum                   = objnum;
 181                                                 fq.ignore_obj_list      = NULL;
 182                                                 fq.flags                                        = FQ_TRANSWALL;
 183
 184                                                 fate = find_vector_intersection(&fq, &hit_data);
 185                                                 if (fate != HIT_NONE)
 186                                                         max_headlight_dist = vm_vec_mag_quick(vm_vec_sub(&tvec, &hit_data.hit_pnt, &Objects[objnum].pos)) + F1_0*4;
 187                                         }
 188                                 }
 189                         // -- for (vv=FrameCount&1; vv<n_render_vertices; vv+=2) {
 190                         for (vv=0; vv<n_render_vertices; vv++) {
 191                                 int                     vertnum;
 192                                 vms_vector      *vertpos;
 193                                 fix                     dist;
 194                                 int                     apply_light;
 195
 196                                 vertnum = render_vertices[vv];
 197                                 if ((vertnum ^ FrameCount) & 1) {
 198                                         vertpos = &Vertices[vertnum];
 199                                         dist = vm_vec_dist_quick(obj_pos, vertpos);
 200                                         apply_light = 0;
 201
 202                                         if ((dist >> headlight_shift) < abs(obji_64)) {
 203
 204                                                 if (dist < MIN_LIGHT_DIST)
 205                                                         dist = MIN_LIGHT_DIST;
 206
 207                                                 //if (Use_fvi_lighting) {
 208                                                 //      if (lighting_cache_visible(vertnum, obj_seg, objnum, obj_pos, obj_seg, vertpos)) {
 209                                                 //              apply_light = 1;
 210                                                 //      }
 211                                                 //} else
 212                                                         apply_light = 1;
 213
 214                                                 if (apply_light) {
 215                                                         if (headlight_shift) {
 216                                                                 fix                     dot;
 217                                                                 vms_vector      vec_to_point;
 218
 219                                                                 vm_vec_sub(&vec_to_point, vertpos, obj_pos);
 220                                                                 vm_vec_normalize_quick(&vec_to_point);          //      MK, Optimization note: You compute distance about 15 lines up, this is partially redundant
 221                                                                 dot = vm_vec_dot(&vec_to_point, &Objects[objnum].orient.fvec);
 222                                                                 if (dot < F1_0/2)
 223                                                                         Dynamic_light[vertnum] += fixdiv(obj_intensity, fixmul(HEADLIGHT_SCALE, dist)); //      Do the normal thing, but darken around headlight.
 224                                                                 else {
 225                                                                         if (Game_mode & GM_MULTI) {
 226                                                                                 if (dist < max_headlight_dist)
 227                                                                                         Dynamic_light[vertnum] += fixmul(fixmul(dot, dot), obj_intensity)/8;
 228                                                                         } else
 229                                                                                 Dynamic_light[vertnum] += fixmul(fixmul(dot, dot), obj_intensity)/8;
 230                                                                 }
 231                                                         } else
 232                                                                 Dynamic_light[vertnum] += fixdiv(obj_intensity, dist);
 233                                                 }
 234                                         }
 235                                 }
 236                         }
 237                 }
 238         }
 239 }
 240
 241 #define FLASH_LEN_FIXED_SECONDS (F1_0/3)
 242 #define FLASH_SCALE                                     (3*F1_0/FLASH_LEN_FIXED_SECONDS)
 243
 244 // ----------------------------------------------------------------------------------------------
 245 void cast_muzzle_flash_light(int n_render_vertices, short *render_vertices)
 246 {
 247         fix current_time;
 248         int     i;
 249         short   time_since_flash;
 250
 251         current_time = timer_get_fixed_seconds();
 252
 253         for (i=0; i<MUZZLE_QUEUE_MAX; i++) {
 254                 if (Muzzle_data[i].create_time) {
 255                         time_since_flash = current_time - Muzzle_data[i].create_time;
 256                         if (time_since_flash < FLASH_LEN_FIXED_SECONDS)
 257                                 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);
 258                         else
 259                                 Muzzle_data[i].create_time = 0;         // turn off this muzzle flash
 260                 }
 261         }
 262 }
 263
 264 //      Translation table to make flares flicker at different rates
 265 fix     Obj_light_xlate[16] =
 266         {0x1234, 0x3321, 0x2468, 0x1735,
 267          0x0123, 0x19af, 0x3f03, 0x232a,
 268          0x2123, 0x39af, 0x0f03, 0x132a,
 269          0x3123, 0x29af, 0x1f03, 0x032a};
 270
 271 //      Flag array of objects lit last frame.  Guaranteed to process this frame if lit last frame.
 272 byte    Lighting_objects[MAX_OBJECTS];
 273
 274 #define MAX_HEADLIGHTS  8
 275 object  *Headlights[MAX_HEADLIGHTS];
 276 int             Num_headlights;
 277
 278 // ---------------------------------------------------------
 279 fix compute_light_intensity(int objnum)
 280 {
 281         object          *obj = &Objects[objnum];
 282         int                     objtype = obj->type;
 283    fix hoardlight,s;
 284
 285         switch (objtype) {
 286                 case OBJ_PLAYER:
 287                          if (Players[obj->id].flags & PLAYER_FLAGS_HEADLIGHT_ON) {
 288                                 if (Num_headlights < MAX_HEADLIGHTS)
 289                                         Headlights[Num_headlights++] = obj;
 290                                 return HEADLIGHT_SCALE;
 291                          } else if ((Game_mode & GM_HOARD) && Players[obj->id].secondary_ammo[PROXIMITY_INDEX]) {
 292
 293                    // If hoard game and player, add extra light based on how many orbs you have
 294                         // Pulse as well.
 295
 296                            hoardlight=i2f(Players[obj->id].secondary_ammo[PROXIMITY_INDEX])/2; //i2f(12));
 297                                 hoardlight++;
 298                       fix_sincos ((GameTime/2) & 0xFFFF,&s,NULL); // probably a bad way to do it
 299                            s+=F1_0;
 300                                 s>>=1;
 301                            hoardlight=fixmul (s,hoardlight);
 302                  //     mprintf ((0,"Hoardlight is %f!\n",f2fl(hoardlight)));
 303                       return (hoardlight);
 304                           }
 305                         else
 306                                 return max(vm_vec_mag_quick(&obj->mtype.phys_info.thrust)/4, F1_0*2) + F1_0/2;
 307                         break;
 308                 case OBJ_FIREBALL:
 309                         if (obj->id != 0xff) {
 310                                 if (obj->lifeleft < F1_0*4)
 311                                         return fixmul(fixdiv(obj->lifeleft, Vclip[obj->id].play_time), Vclip[obj->id].light_value);
 312                                 else
 313                                         return Vclip[obj->id].light_value;
 314                         } else
 315                                  return 0;
 316                         break;
 317                 case OBJ_ROBOT:
 318                         return F1_0*Robot_info[obj->id].lightcast;
 319                         break;
 320                 case OBJ_WEAPON: {
 321                         fix tval = Weapon_info[obj->id].light;
 322                         if (Game_mode & GM_MULTI)
 323                                 if (obj->id == OMEGA_ID)
 324                                         if (d_rand() > 8192)
 325                                                 return 0;               //      3/4 of time, omega blobs will cast 0 light!
 326
 327                         if (obj->id == FLARE_ID )
 328                                 return 2* (min(tval, obj->lifeleft) + ((GameTime ^ Obj_light_xlate[objnum&0x0f]) & 0x3fff));
 329                         else
 330                                 return tval;
 331                 }
 332
 333                 case OBJ_MARKER: {
 334                         fix     lightval = obj->lifeleft;
 335
 336                         lightval &= 0xffff;
 337
 338                         lightval = 8 * abs(F1_0/2 - lightval);
 339
 340                         if (obj->lifeleft < F1_0*1000)
 341                                 obj->lifeleft += F1_0;  //      Make sure this object doesn't go out.
 342
 343                         return lightval;
 344                 }
 345
 346                 case OBJ_POWERUP:
 347                         return Powerup_info[obj->id].light;
 348                         break;
 349                 case OBJ_DEBRIS:
 350                         return F1_0/4;
 351                         break;
 352                 case OBJ_LIGHT:
 353                         return obj->ctype.light_info.intensity;
 354                         break;
 355                 default:
 356                         return 0;
 357                         break;
 358         }
 359 }
 360
 361 // ----------------------------------------------------------------------------------------------
 362 void set_dynamic_light(void)
 363 {
 364         int     vv;
 365         int     objnum;
 366         int     n_render_vertices;
 367         short   render_vertices[MAX_VERTICES];
 368         byte    render_vertex_flags[MAX_VERTICES];
 369         int     render_seg,segnum, v;
 370         byte    new_lighting_objects[MAX_OBJECTS];
 371
 372         Num_headlights = 0;
 373
 374         if (!Do_dynamic_light)
 375                 return;
 376
 377 //if (Use_fvi_lighting)
 378 //      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));
 379
 380         memset(render_vertex_flags, 0, Highest_vertex_index+1);
 381
 382         //      Create list of vertices that need to be looked at for setting of ambient light.
 383         n_render_vertices = 0;
 384         for (render_seg=0; render_seg<N_render_segs; render_seg++) {
 385                 segnum = Render_list[render_seg];
 386                 if (segnum != -1) {
 387                         short   *vp = Segments[segnum].verts;
 388                         for (v=0; v<MAX_VERTICES_PER_SEGMENT; v++) {
 389                                 int     vnum = vp[v];
 390                                 if (vnum<0 || vnum>Highest_vertex_index) {
 391                                         Int3();         //invalid vertex number
 392                                         continue;       //ignore it, and go on to next one
 393                                 }
 394                                 if (!render_vertex_flags[vnum]) {
 395                                         render_vertex_flags[vnum] = 1;
 396                                         render_vertices[n_render_vertices++] = vnum;
 397                                 }
 398                                 //--old way-- for (s=0; s<n_render_vertices; s++)
 399                                 //--old way--   if (render_vertices[s] == vnum)
 400                                 //--old way--           break;
 401                                 //--old way-- if (s == n_render_vertices)
 402                                 //--old way--   render_vertices[n_render_vertices++] = vnum;
 403                         }
 404                 }
 405         }
 406
 407         // -- for (vertnum=FrameCount&1; vertnum<n_render_vertices; vertnum+=2) {
 408         for (vv=0; vv<n_render_vertices; vv++) {
 409                 int     vertnum;
 410
 411                 vertnum = render_vertices[vv];
 412                 Assert(vertnum >= 0 && vertnum <= Highest_vertex_index);
 413                 if ((vertnum ^ FrameCount) & 1)
 414                         Dynamic_light[vertnum] = 0;
 415         }
 416
 417         cast_muzzle_flash_light(n_render_vertices, render_vertices);
 418
 419         for (objnum=0; objnum<=Highest_object_index; objnum++)
 420                 new_lighting_objects[objnum] = 0;
 421
 422         //      July 5, 1995: New faster dynamic lighting code.  About 5% faster on the PC (un-optimized).
 423         //      Only objects which are in rendered segments cast dynamic light.  We might wad6 to extend this
 424         //      one or two segments if we notice light changing as objects go offscreen.  I couldn't see any
 425         //      serious visual degradation.  In fact, I could see no humorous degradation, either. --MK
 426         for (render_seg=0; render_seg<N_render_segs; render_seg++) {
 427                 int     segnum = Render_list[render_seg];
 428
 429                 objnum = Segments[segnum].objects;
 430
 431                 while (objnum != -1) {
 432                         object          *obj = &Objects[objnum];
 433                         vms_vector      *objpos = &obj->pos;
 434                         fix                     obj_intensity;
 435
 436                         obj_intensity = compute_light_intensity(objnum);
 437
 438                         if (obj_intensity) {
 439                                 apply_light(obj_intensity, obj->segnum, objpos, n_render_vertices, render_vertices, obj-Objects);
 440                                 new_lighting_objects[objnum] = 1;
 441                         }
 442
 443                         objnum = obj->next;
 444                 }
 445         }
 446
 447         //      Now, process all lights from last frame which haven't been processed this frame.
 448         for (objnum=0; objnum<=Highest_object_index; objnum++) {
 449                 //      In multiplayer games, process even unprocessed objects every 4th frame, else don't know about player sneaking up.
 450                 if ((Lighting_objects[objnum]) || ((Game_mode & GM_MULTI) && (((objnum ^ FrameCount) & 3) == 0))) {
 451                         if (!new_lighting_objects[objnum]) {
 452                                 //      Lighted last frame, but not this frame.  Get intensity...
 453                                 object          *obj = &Objects[objnum];
 454                                 vms_vector      *objpos = &obj->pos;
 455                                 fix                     obj_intensity;
 456
 457                                 obj_intensity = compute_light_intensity(objnum);
 458
 459                                 if (obj_intensity) {
 460                                         apply_light(obj_intensity, obj->segnum, objpos, n_render_vertices, render_vertices, objnum);
 461                                         Lighting_objects[objnum] = 1;
 462                                 } else
 463                                         Lighting_objects[objnum] = 0;
 464                         }
 465                 } else {
 466                         //      Not lighted last frame, so we don't need to light it.  (Already lit if casting light this frame.)
 467                         //      But copy value from new_lighting_objects to update Lighting_objects array.
 468                         Lighting_objects[objnum] = new_lighting_objects[objnum];
 469                 }
 470         }
 471 }
 472
 473 // ---------------------------------------------------------
 474
 475 void toggle_headlight_active()
 476 {
 477         if (Players[Player_num].flags & PLAYER_FLAGS_HEADLIGHT) {
 478                 Players[Player_num].flags ^= PLAYER_FLAGS_HEADLIGHT_ON;
 479 #ifdef NETWORK
 480                 if (Game_mode & GM_MULTI)
 481                         multi_send_flags(Player_num);
 482 #endif
 483         }
 484 }
 485
 486 #define HEADLIGHT_BOOST_SCALE 8         //how much to scale light when have headlight boost
 487
 488 fix     Beam_brightness = (F1_0/2);     //global saying how bright the light beam is
 489
 490 #define MAX_DIST_LOG    6                                                       //log(MAX_DIST-expressed-as-integer)
 491 #define MAX_DIST                (f1_0<<MAX_DIST_LOG)    //no light beyond this dist
 492
 493 fix compute_headlight_light_on_object(object *objp)
 494 {
 495         int     i;
 496         fix     light;
 497
 498         //      Let's just illuminate players and robots for speed reasons, ok?
 499         if ((objp->type != OBJ_ROBOT) && (objp->type    != OBJ_PLAYER))
 500                 return 0;
 501
 502         light = 0;
 503
 504         for (i=0; i<Num_headlights; i++) {
 505                 fix                     dot, dist;
 506                 vms_vector      vec_to_obj;
 507                 object          *light_objp;
 508
 509                 light_objp = Headlights[i];
 510
 511                 vm_vec_sub(&vec_to_obj, &objp->pos, &light_objp->pos);
 512                 dist = vm_vec_normalize_quick(&vec_to_obj);
 513                 if (dist > 0) {
 514                         dot = vm_vec_dot(&light_objp->orient.fvec, &vec_to_obj);
 515
 516                         if (dot < F1_0/2)
 517                                 light += fixdiv(HEADLIGHT_SCALE, fixmul(HEADLIGHT_SCALE, dist));        //      Do the normal thing, but darken around headlight.
 518                         else
 519                                 light += fixmul(fixmul(dot, dot), HEADLIGHT_SCALE)/8;
 520                 }
 521         }
 522
 523         return light;
 524 }
 525
 526
 527 // -- Unused -- //Compute the lighting from the headlight for a given vertex on a face.
 528 // -- Unused -- //Takes:
 529 // -- Unused -- //  point - the 3d coords of the point
 530 // -- Unused -- //  face_light - a scale factor derived from the surface normal of the face
 531 // -- Unused -- //If no surface normal effect is wanted, pass F1_0 for face_light
 532 // -- Unused -- fix compute_headlight_light(vms_vector *point,fix face_light)
 533 // -- Unused -- {
 534 // -- Unused --         fix light;
 535 // -- Unused --         int use_beam = 0;               //flag for beam effect
 536 // -- Unused --
 537 // -- Unused --         light = Beam_brightness;
 538 // -- Unused --
 539 // -- 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) {
 540 // -- Unused --                 light *= HEADLIGHT_BOOST_SCALE;
 541 // -- Unused --                 use_beam = 1;   //give us beam effect
 542 // -- Unused --         }
 543 // -- Unused --
 544 // -- Unused --         if (light) {                            //if no beam, don't bother with the rest of this
 545 // -- Unused --                 fix point_dist;
 546 // -- Unused --
 547 // -- Unused --                 point_dist = vm_vec_mag_quick(point);
 548 // -- Unused --
 549 // -- Unused --                 if (point_dist >= MAX_DIST)
 550 // -- Unused --
 551 // -- Unused --                         light = 0;
 552 // -- Unused --
 553 // -- Unused --                 else {
 554 // -- Unused --                         fix dist_scale,face_scale;
 555 // -- Unused --
 556 // -- Unused --                         dist_scale = (MAX_DIST - point_dist) >> MAX_DIST_LOG;
 557 // -- Unused --                         light = fixmul(light,dist_scale);
 558 // -- Unused --
 559 // -- Unused --                         if (face_light < 0)
 560 // -- Unused --                                 face_light = 0;
 561 // -- Unused --
 562 // -- Unused --                         face_scale = f1_0/4 + face_light/2;
 563 // -- Unused --                         light = fixmul(light,face_scale);
 564 // -- Unused --
 565 // -- Unused --                         if (use_beam) {
 566 // -- Unused --                                 fix beam_scale;
 567 // -- Unused --
 568 // -- Unused --                                 if (face_light > f1_0*3/4 && point->z > i2f(12)) {
 569 // -- Unused --                                         beam_scale = fixdiv(point->z,point_dist);
 570 // -- Unused --                                         beam_scale = fixmul(beam_scale,beam_scale);     //square it
 571 // -- Unused --                                         light = fixmul(light,beam_scale);
 572 // -- Unused --                                 }
 573 // -- Unused --                         }
 574 // -- Unused --                 }
 575 // -- Unused --         }
 576 // -- Unused --
 577 // -- Unused --         return light;
 578 // -- Unused -- }
 579
 580 //compute the average dynamic light in a segment.  Takes the segment number
 581 fix compute_seg_dynamic_light(int segnum)
 582 {
 583         fix sum;
 584         segment *seg;
 585         short *verts;
 586
 587         seg = &Segments[segnum];
 588
 589         verts = seg->verts;
 590         sum = 0;
 591
 592         sum += Dynamic_light[*verts++];
 593         sum += Dynamic_light[*verts++];
 594         sum += Dynamic_light[*verts++];
 595         sum += Dynamic_light[*verts++];
 596         sum += Dynamic_light[*verts++];
 597         sum += Dynamic_light[*verts++];
 598         sum += Dynamic_light[*verts++];
 599         sum += Dynamic_light[*verts];
 600
 601         return sum >> 3;
 602
 603 }
 604
 605 fix object_light[MAX_OBJECTS];
 606 int object_sig[MAX_OBJECTS];
 607 object *old_viewer;
 608 int reset_lighting_hack;
 609
 610 #define LIGHT_RATE i2f(4)               //how fast the light ramps up
 611
 612 void start_lighting_frame(object *viewer)
 613 {
 614         reset_lighting_hack = (viewer != old_viewer);
 615
 616         old_viewer = viewer;
 617 }
 618
 619 //compute the lighting for an object.  Takes a pointer to the object,
 620 //and possibly a rotated 3d point.  If the point isn't specified, the
 621 //object's center point is rotated.
 622 fix compute_object_light(object *obj,vms_vector *rotated_pnt)
 623 {
 624         fix light;
 625         g3s_point objpnt;
 626         int objnum = obj-Objects;
 627
 628         if (!rotated_pnt) {
 629                 g3_rotate_point(&objpnt,&obj->pos);
 630                 rotated_pnt = &objpnt.p3_vec;
 631         }
 632
 633         //First, get static light for this segment
 634
 635         light = Segment2s[obj->segnum].static_light;
 636
 637         //return light;
 638
 639
 640         //Now, maybe return different value to smooth transitions
 641
 642         if (!reset_lighting_hack && object_sig[objnum] == obj->signature) {
 643                 fix delta_light,frame_delta;
 644
 645                 delta_light = light - object_light[objnum];
 646
 647                 frame_delta = fixmul(LIGHT_RATE,FrameTime);
 648
 649                 if (abs(delta_light) <= frame_delta)
 650
 651                         object_light[objnum] = light;           //we've hit the goal
 652
 653                 else
 654
 655                         if (delta_light < 0)
 656                                 light = object_light[objnum] -= frame_delta;
 657                         else
 658                                 light = object_light[objnum] += frame_delta;
 659
 660         }
 661         else {          //new object, initialize
 662
 663                 object_sig[objnum] = obj->signature;
 664                 object_light[objnum] = light;
 665         }
 666
 667
 668
 669         //Next, add in headlight on this object
 670
 671         // -- Matt code: light += compute_headlight_light(rotated_pnt,f1_0);
 672         light += compute_headlight_light_on_object(obj);
 673
 674         //Finally, add in dynamic light for this segment
 675
 676         light += compute_seg_dynamic_light(obj->segnum);
 677
 678
 679         return light;
 680 }
 681
 682