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