main/terrain.c

   1 /* $Id: terrain.c,v 1.5 2004-08-28 23:17:45 schaffner Exp $ */
   2 /*
   3 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
   4 SOFTWARE CORPORATION ("PARALLAX").  PARALLAX, IN DISTRIBUTING THE CODE TO
   5 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
   6 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
   7 IN USING, DISPLAYING,  AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
   8 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
   9 FREE PURPOSES.  IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
  10 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES.  THE END-USER UNDERSTANDS
  11 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
  12 COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
  13 */
  14
  15 /*
  16  *
  17  * Code to render cool external-scene terrain
  18  *
  19  */
  20
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <conf.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include "3d.h"
  31 #include "error.h"
  32 #include "gr.h"
  33 #include "texmap.h"
  34 #include "iff.h"
  35 #include "u_mem.h"
  36 #include "mono.h"
  37
  38 #include "inferno.h"
  39 #include "textures.h"
  40 #include "object.h"
  41 #include "endlevel.h"
  42 #include "fireball.h"
  43 #include "render.h"
  44
  45 #define GRID_MAX_SIZE   64
  46 #define GRID_SCALE      i2f(2*20)
  47 #define HEIGHT_SCALE    f1_0
  48
  49 int grid_w,grid_h;
  50
  51 g3s_uvl uvl_list1[] = { {0,0,0}, {f1_0,0,0},  {0,f1_0,0} };
  52 g3s_uvl uvl_list2[] = { {f1_0,0,0}, {f1_0,f1_0,0},  {0,f1_0,0} };
  53
  54 ubyte *height_array;
  55 ubyte *light_array;
  56
  57 #define HEIGHT(_i,_j) (height_array[(_i)*grid_w+(_j)])
  58 #define LIGHT(_i,_j) light_array[(_i)*grid_w+(_j)]
  59
  60 //!!#define HEIGHT(_i,_j)   height_array[(grid_h-1-j)*grid_w+(_i)]
  61 //!!#define LIGHT(_i,_j)    light_array[(grid_h-1-j)*grid_w+(_i)]
  62
  63 #define LIGHTVAL(_i,_j) (((fix) LIGHT(_i,_j))<<8)
  64
  65 g3s_point save_row[GRID_MAX_SIZE];
  66
  67 vms_vector start_point;
  68
  69 grs_bitmap *terrain_bm;
  70
  71 int terrain_outline=0;
  72
  73 int org_i,org_j;
  74
  75 int mine_tiles_drawn;    //flags to tell if all 4 tiles under mine have drawn
  76
  77
  78 // LINT: adding function prototypes
  79 void build_light_table(void);
  80 void free_light_table(void);
  81
  82 // ------------------------------------------------------------------------
  83 void draw_cell(int i,int j,g3s_point *p0,g3s_point *p1,g3s_point *p2,g3s_point *p3)
  84 {
  85         g3s_point *pointlist[3];
  86
  87         pointlist[0] = p0;
  88         pointlist[1] = p1;
  89         pointlist[2] = p3;
  90         uvl_list1[0].l = LIGHTVAL(i,j);
  91         uvl_list1[1].l = LIGHTVAL(i,j+1);
  92         uvl_list1[2].l = LIGHTVAL(i+1,j);
  93
  94         uvl_list1[0].u = (i)*f1_0/4; uvl_list1[0].v = (j)*f1_0/4;
  95         uvl_list1[1].u = (i)*f1_0/4; uvl_list1[1].v = (j+1)*f1_0/4;
  96         uvl_list1[2].u = (i+1)*f1_0/4;   uvl_list1[2].v = (j)*f1_0/4;
  97
  98         g3_check_and_draw_tmap(3,pointlist,uvl_list1,terrain_bm,NULL,NULL);
  99         if (terrain_outline) {
 100                 int lsave=Lighting_on;
 101                 Lighting_on=0;
 102                 gr_setcolor(BM_XRGB(31,0,0));
 103                 g3_draw_line(pointlist[0],pointlist[1]);
 104                 g3_draw_line(pointlist[2],pointlist[0]);
 105                 Lighting_on=lsave;
 106         }
 107
 108         pointlist[0] = p1;
 109         pointlist[1] = p2;
 110         uvl_list2[0].l = LIGHTVAL(i,j+1);
 111         uvl_list2[1].l = LIGHTVAL(i+1,j+1);
 112         uvl_list2[2].l = LIGHTVAL(i+1,j);
 113
 114         uvl_list2[0].u = (i)*f1_0/4; uvl_list2[0].v = (j+1)*f1_0/4;
 115         uvl_list2[1].u = (i+1)*f1_0/4;   uvl_list2[1].v = (j+1)*f1_0/4;
 116         uvl_list2[2].u = (i+1)*f1_0/4;   uvl_list2[2].v = (j)*f1_0/4;
 117
 118         g3_check_and_draw_tmap(3,pointlist,uvl_list2,terrain_bm,NULL,NULL);
 119         if (terrain_outline) {
 120                 int lsave=Lighting_on;
 121                 Lighting_on=0;
 122                 gr_setcolor(BM_XRGB(31,0,0));
 123                 g3_draw_line(pointlist[0],pointlist[1]);
 124                 g3_draw_line(pointlist[1],pointlist[2]);
 125                 g3_draw_line(pointlist[2],pointlist[0]);
 126                 Lighting_on=lsave;
 127         }
 128
 129         if (i==org_i && j==org_j)
 130                 mine_tiles_drawn |= 1;
 131         if (i==org_i-1 && j==org_j)
 132                 mine_tiles_drawn |= 2;
 133         if (i==org_i && j==org_j-1)
 134                 mine_tiles_drawn |= 4;
 135         if (i==org_i-1 && j==org_j-1)
 136                 mine_tiles_drawn |= 8;
 137
 138         if (mine_tiles_drawn == 0xf) {
 139                 render_mine(exit_segnum, 0, 0);
 140                 //draw_exit_model();
 141                 mine_tiles_drawn=-1;
 142                 //if (ext_expl_playing)
 143                 //      draw_fireball(&external_explosion);
 144         }
 145
 146 }
 147
 148 vms_vector y_cache[256];
 149 ubyte yc_flags[256];
 150
 151 extern vms_matrix surface_orient;
 152
 153 vms_vector *get_dy_vec(int h)
 154 {
 155         vms_vector *dyp;
 156
 157         dyp = &y_cache[h];
 158
 159         if (!yc_flags[h]) {
 160                 vms_vector tv;
 161
 162                 //@@g3_rotate_delta_y(dyp,h*HEIGHT_SCALE);
 163
 164                 vm_vec_copy_scale(&tv,&surface_orient.uvec,h*HEIGHT_SCALE);
 165                 g3_rotate_delta_vec(dyp,&tv);
 166
 167                 yc_flags[h] = 1;
 168         }
 169
 170         return dyp;
 171
 172 }
 173
 174 int im=1;
 175
 176 void render_terrain(vms_vector *org_point,int org_2dx,int org_2dy)
 177 {
 178         vms_vector delta_i,delta_j;             //delta_y;
 179         g3s_point p,last_p,save_p_low,save_p_high;
 180         g3s_point last_p2;
 181         int i,j;
 182         int low_i,high_i,low_j,high_j;
 183         int viewer_i,viewer_j;
 184         vms_vector tv;
 185
 186         mine_tiles_drawn = 0;   //clear flags
 187
 188         org_i = org_2dy;
 189         org_j = org_2dx;
 190
 191         low_i = 0;  high_i = grid_w-1;
 192         low_j = 0;  high_j = grid_h-1;
 193
 194         //@@start_point.x = org_point->x - GRID_SCALE*(org_i - low_i);
 195         //@@start_point.z = org_point->z - GRID_SCALE*(org_j - low_j);
 196         //@@start_point.y = org_point->y;
 197
 198         memset(yc_flags,0,256);
 199
 200         //Lighting_on = 0;
 201         Interpolation_method = im;
 202
 203         vm_vec_copy_scale(&tv,&surface_orient.rvec,GRID_SCALE);
 204         g3_rotate_delta_vec(&delta_i,&tv);
 205         vm_vec_copy_scale(&tv,&surface_orient.fvec,GRID_SCALE);
 206         g3_rotate_delta_vec(&delta_j,&tv);
 207
 208         vm_vec_scale_add(&start_point,org_point,&surface_orient.rvec,-(org_i - low_i)*GRID_SCALE);
 209         vm_vec_scale_add2(&start_point,&surface_orient.fvec,-(org_j - low_j)*GRID_SCALE);
 210
 211         vm_vec_sub(&tv,&Viewer->pos,&start_point);
 212         viewer_i = vm_vec_dot(&tv,&surface_orient.rvec) / GRID_SCALE;
 213         viewer_j = vm_vec_dot(&tv,&surface_orient.fvec) / GRID_SCALE;
 214
 215 //mprintf((0,"viewer_i,j = %d,%d\n",viewer_i,viewer_j));
 216
 217         g3_rotate_point(&last_p,&start_point);
 218         save_p_low = last_p;
 219
 220         for (j=low_j;j<=high_j;j++) {
 221                 g3_add_delta_vec(&save_row[j],&last_p,get_dy_vec(HEIGHT(low_i,j)));
 222                 if (j==high_j)
 223                         save_p_high = last_p;
 224                 else
 225                         g3_add_delta_vec(&last_p,&last_p,&delta_j);
 226         }
 227
 228         for (i=low_i;i<viewer_i;i++) {
 229
 230                 g3_add_delta_vec(&save_p_low,&save_p_low,&delta_i);
 231                 last_p = save_p_low;
 232                 g3_add_delta_vec(&last_p2,&last_p,get_dy_vec(HEIGHT(i+1,low_j)));
 233
 234                 for (j=low_j;j<viewer_j;j++) {
 235                         g3s_point p2;
 236
 237                         g3_add_delta_vec(&p,&last_p,&delta_j);
 238                         g3_add_delta_vec(&p2,&p,get_dy_vec(HEIGHT(i+1,j+1)));
 239
 240                         draw_cell(i,j,&save_row[j],&save_row[j+1],&p2,&last_p2);
 241
 242                         last_p = p;
 243                         save_row[j] = last_p2;
 244                         last_p2 = p2;
 245
 246                 }
 247
 248                 vm_vec_negate(&delta_j);                        //don't have a delta sub...
 249
 250                 g3_add_delta_vec(&save_p_high,&save_p_high,&delta_i);
 251                 last_p = save_p_high;
 252                 g3_add_delta_vec(&last_p2,&last_p,get_dy_vec(HEIGHT(i+1,high_j)));
 253
 254                 for (j=high_j-1;j>=viewer_j;j--) {
 255                         g3s_point p2;
 256
 257                         g3_add_delta_vec(&p,&last_p,&delta_j);
 258                         g3_add_delta_vec(&p2,&p,get_dy_vec(HEIGHT(i+1,j)));
 259
 260                         draw_cell(i,j,&save_row[j],&save_row[j+1],&last_p2,&p2);
 261
 262                         last_p = p;
 263                         save_row[j+1] = last_p2;
 264                         last_p2 = p2;
 265
 266                 }
 267
 268                 save_row[j+1] = last_p2;
 269
 270                 vm_vec_negate(&delta_j);                //restore sign of j
 271
 272         }
 273
 274         //now do i from other end
 275
 276         vm_vec_negate(&delta_i);                //going the other way now...
 277
 278         //@@start_point.x += (high_i-low_i)*GRID_SCALE;
 279         vm_vec_scale_add2(&start_point,&surface_orient.rvec,(high_i-low_i)*GRID_SCALE);
 280         g3_rotate_point(&last_p,&start_point);
 281         save_p_low = last_p;
 282
 283         for (j=low_j;j<=high_j;j++) {
 284                 g3_add_delta_vec(&save_row[j],&last_p,get_dy_vec(HEIGHT(high_i,j)));
 285                 if (j==high_j)
 286                         save_p_high = last_p;
 287                 else
 288                         g3_add_delta_vec(&last_p,&last_p,&delta_j);
 289         }
 290
 291         for (i=high_i-1;i>=viewer_i;i--) {
 292
 293                 g3_add_delta_vec(&save_p_low,&save_p_low,&delta_i);
 294                 last_p = save_p_low;
 295                 g3_add_delta_vec(&last_p2,&last_p,get_dy_vec(HEIGHT(i,low_j)));
 296
 297                 for (j=low_j;j<viewer_j;j++) {
 298                         g3s_point p2;
 299
 300                         g3_add_delta_vec(&p,&last_p,&delta_j);
 301                         g3_add_delta_vec(&p2,&p,get_dy_vec(HEIGHT(i,j+1)));
 302
 303                         draw_cell(i,j,&last_p2,&p2,&save_row[j+1],&save_row[j]);
 304
 305                         last_p = p;
 306                         save_row[j] = last_p2;
 307                         last_p2 = p2;
 308
 309                 }
 310
 311                 vm_vec_negate(&delta_j);                        //don't have a delta sub...
 312
 313                 g3_add_delta_vec(&save_p_high,&save_p_high,&delta_i);
 314                 last_p = save_p_high;
 315                 g3_add_delta_vec(&last_p2,&last_p,get_dy_vec(HEIGHT(i,high_j)));
 316
 317                 for (j=high_j-1;j>=viewer_j;j--) {
 318                         g3s_point p2;
 319
 320                         g3_add_delta_vec(&p,&last_p,&delta_j);
 321                         g3_add_delta_vec(&p2,&p,get_dy_vec(HEIGHT(i,j)));
 322
 323                         draw_cell(i,j,&p2,&last_p2,&save_row[j+1],&save_row[j]);
 324
 325                         last_p = p;
 326                         save_row[j+1] = last_p2;
 327                         last_p2 = p2;
 328
 329                 }
 330
 331                 save_row[j+1] = last_p2;
 332
 333                 vm_vec_negate(&delta_j);                //restore sign of j
 334
 335         }
 336
 337 }
 338
 339 void free_height_array()
 340 {
 341         d_free(height_array);
 342 }
 343
 344 void load_terrain(char *filename)
 345 {
 346         grs_bitmap height_bitmap;
 347         int iff_error;
 348         int i,j;
 349         ubyte h,min_h,max_h;
 350
 351         iff_error = iff_read_bitmap(filename,&height_bitmap,BM_LINEAR,NULL);
 352         if (iff_error != IFF_NO_ERROR) {
 353                 mprintf((1, "File %s - IFF error: %s",filename,iff_errormsg(iff_error)));
 354                 Error("File %s - IFF error: %s",filename,iff_errormsg(iff_error));
 355         }
 356
 357         if (height_array)
 358                 d_free(height_array);
 359         else
 360                 atexit(free_height_array);              //first time
 361
 362         grid_w = height_bitmap.bm_w;
 363         grid_h = height_bitmap.bm_h;
 364
 365         Assert(grid_w <= GRID_MAX_SIZE);
 366         Assert(grid_h <= GRID_MAX_SIZE);
 367
 368         height_array = height_bitmap.bm_data;
 369
 370         max_h=0; min_h=255;
 371         for (i=0;i<grid_w;i++)
 372                 for (j=0;j<grid_h;j++) {
 373
 374                         h = HEIGHT(i,j);
 375
 376                         if (h > max_h)
 377                                 max_h = h;
 378
 379                         if (h < min_h)
 380                                 min_h = h;
 381                 }
 382
 383         for (i=0;i<grid_w;i++)
 384                 for (j=0;j<grid_h;j++)
 385                         HEIGHT(i,j) -= min_h;
 386
 387
 388 //      d_free(height_bitmap.bm_data);
 389
 390         terrain_bm = terrain_bitmap;
 391
 392         build_light_table();
 393 }
 394
 395
 396 void get_pnt(vms_vector *p,int i,int j)
 397 {
 398         p->x = GRID_SCALE*i;
 399         p->z = GRID_SCALE*j;
 400         p->y = HEIGHT(i,j)*HEIGHT_SCALE;
 401 }
 402
 403 vms_vector light = {0x2e14,0xe8f5,0x5eb8};
 404
 405 fix get_face_light(vms_vector *p0,vms_vector *p1,vms_vector *p2)
 406 {
 407         vms_vector norm;
 408
 409         vm_vec_normal(&norm,p0,p1,p2);
 410
 411         return -vm_vec_dot(&norm,&light);
 412
 413 }
 414
 415
 416 fix get_avg_light(int i,int j)
 417 {
 418         vms_vector pp,p[6];
 419         fix sum;
 420         int f;
 421
 422         get_pnt(&pp,i,j);
 423         get_pnt(&p[0],i-1,j);
 424         get_pnt(&p[1],i,j-1);
 425         get_pnt(&p[2],i+1,j-1);
 426         get_pnt(&p[3],i+1,j);
 427         get_pnt(&p[4],i,j+1);
 428         get_pnt(&p[5],i-1,j+1);
 429
 430         for (f=0,sum=0;f<6;f++)
 431                 sum += get_face_light(&pp,&p[f],&p[(f+1)%5]);
 432
 433         return sum/6;
 434 }
 435
 436 void free_light_table()
 437 {
 438         if (light_array)
 439                 d_free(light_array);
 440
 441 }
 442
 443 void build_light_table()
 444 {
 445         int i,j;
 446         fix l,l2,min_l=0x7fffffff,max_l=0;
 447
 448
 449         if (light_array)
 450                 d_free(light_array);
 451         else
 452                 atexit(free_light_table);               //first time
 453
 454         MALLOC(light_array,ubyte,grid_w*grid_h);
 455
 456         for (i=1;i<grid_w;i++)
 457                 for (j=1;j<grid_h;j++) {
 458                         l = get_avg_light(i,j);
 459
 460                         if (l > max_l)
 461                                 max_l = l;
 462
 463                         if (l < min_l)
 464                                 min_l = l;
 465
 466                         //printf("light %2d,%2d = %8x\n",i,j,l);
 467                 }
 468
 469         for (i=1;i<grid_w;i++)
 470                 for (j=1;j<grid_h;j++) {
 471
 472                         l = get_avg_light(i,j);
 473
 474                         if (min_l == max_l) {
 475                                 LIGHT(i,j) = l>>8;
 476                                 continue;
 477                         }
 478
 479                         l2 = fixdiv((l-min_l),(max_l-min_l));
 480
 481                         if (l2==f1_0)
 482                                 l2--;
 483
 484                         LIGHT(i,j) = l2>>8;
 485
 486                         //printf("light %2d,%2d = %4x\n",i,j,l2>>8);
 487
 488                 }
 489 }