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