attempt to support d1 for mac mission
[btb/d2x.git] / main / fvi.c
1
2 #define NEW_FVI_STUFF 1
3
4 /*
5 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
6 SOFTWARE CORPORATION ("PARALLAX").  PARALLAX, IN DISTRIBUTING THE CODE TO
7 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
8 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
9 IN USING, DISPLAYING,  AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
10 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
11 FREE PURPOSES.  IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
12 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES.  THE END-USER UNDERSTANDS
13 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.  
14 COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
15 */
16
17 #ifdef HAVE_CONFIG_H
18 #include <conf.h>
19 #endif
20
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24
25 #ifdef MACINTOSH
26 #include <Memory.h>
27 #endif
28
29 #include "pstypes.h"
30 #include "u_mem.h"
31 #include "error.h"
32 #include "mono.h"
33
34 #include "inferno.h"
35 #include "fvi.h"
36 #include "segment.h"
37 #include "object.h"
38 #include "wall.h"
39 #include "laser.h"
40 #include "rle.h"
41 #include "robot.h"
42 #include "piggy.h"
43 #include "player.h"
44
45 extern int Physics_cheat_flag;
46
47 #define face_type_num(nfaces,face_num,tri_edge) ((nfaces==1)?0:(tri_edge*2 + face_num))
48
49 #include "fvi_a.h"
50
51 //find the point on the specified plane where the line intersects
52 //returns true if point found, false if line parallel to plane
53 //new_pnt is the found point on the plane
54 //plane_pnt & plane_norm describe the plane
55 //p0 & p1 are the ends of the line
56 int find_plane_line_intersection(vms_vector *new_pnt,vms_vector *plane_pnt,vms_vector *plane_norm,vms_vector *p0,vms_vector *p1,fix rad)
57 {
58         vms_vector d,w;
59         fix num,den;
60
61         vm_vec_sub(&d,p1,p0);
62         vm_vec_sub(&w,p0,plane_pnt);
63
64         num =  vm_vec_dot(plane_norm,&w);
65         den = -vm_vec_dot(plane_norm,&d);
66
67 //Why does this assert hit so often
68 //      Assert(num > -rad);
69
70         num -= rad;                     //move point out by rad
71
72         //check for various bad values
73
74         if ( (den==0) ||                                        //moving parallel to wall, so can't hit it
75                   ((den>0) &&
76                         ( (num>den) ||                          //frac greater than one
77                      (-num>>15)>=den)) ||       //will overflow (large negative)
78                   (den<0 && num<den))           //frac greater than one
79                 return 0;
80  
81 //if (num>0) {mprintf(1,"HEY! num>0 in FVI!!!"); return 0;}
82 //??    Assert(num>=0);
83 //    Assert(num >= den);
84
85         //do check for potenial overflow
86         {
87                 fix k;
88
89                 if (labs(num)/(f1_0/2) >= labs(den)) {Int3(); return 0;}
90                 k = fixdiv(num,den);
91
92                 Assert(k<=f1_0);                //should be trapped above
93
94 //              Assert(k>=0);
95                 if (oflow_check(d.x,k) || oflow_check(d.y,k) || oflow_check(d.z,k)) return 0;
96                 //Note: it is ok for k to be greater than 1, since this might mean
97                 //that an object with a non-zero radius that moved from p0 to p1 
98                 //actually hit the wall on the "other side" of p0.
99         }
100
101         vm_vec_scale2(&d,num,den);
102
103         vm_vec_add(new_pnt,p0,&d);
104
105         //we should have vm_vec_scale2_add2()
106
107         return 1;
108
109 }
110
111 typedef struct vec2d {
112         fix i,j;
113 } vec2d;
114
115 //given largest componant of normal, return i & j
116 //if largest componant is negative, swap i & j
117 int ij_table[3][2] =        {
118                                                         {2,1},          //pos x biggest
119                                                         {0,2},          //pos y biggest
120                                                         {1,0},          //pos z biggest
121                                                 };
122
123 //intersection types
124 #define IT_NONE 0       //doesn't touch face at all
125 #define IT_FACE 1       //touches face
126 #define IT_EDGE 2       //touches edge of face
127 #define IT_POINT        3       //touches vertex
128
129 //see if a point in inside a face by projecting into 2d
130 uint check_point_to_face(vms_vector *checkp, side *s,int facenum,int nv,int *vertex_list)
131 {
132         vms_vector_array *checkp_array;
133         vms_vector_array norm;
134         vms_vector t;
135         int biggest;
136 ///
137         int i,j,edge;
138         uint edgemask;
139         fix check_i,check_j;
140         vms_vector_array *v0,*v1;
141
142         #ifdef COMPACT_SEGS
143                 get_side_normal(sp, s-sp->sides, facenum, (vms_vector *)&norm );
144         #else
145                 memcpy( &norm, &s->normals[facenum], sizeof(vms_vector_array));
146         #endif
147         checkp_array = (vms_vector_array *)checkp;
148
149         //now do 2d check to see if point is in side
150
151         //project polygon onto plane by finding largest component of normal
152         t.x = labs(norm.xyz[0]); t.y = labs(norm.xyz[1]); t.z = labs(norm.xyz[2]);
153
154         if (t.x > t.y) if (t.x > t.z) biggest=0; else biggest=2;
155         else if (t.y > t.z) biggest=1; else biggest=2;
156
157         if (norm.xyz[biggest] > 0) {
158                 i = ij_table[biggest][0];
159                 j = ij_table[biggest][1];
160         }
161         else {
162                 i = ij_table[biggest][1];
163                 j = ij_table[biggest][0];
164         }
165
166         //now do the 2d problem in the i,j plane
167
168         check_i = checkp_array->xyz[i];
169         check_j = checkp_array->xyz[j];
170
171         for (edge=edgemask=0;edge<nv;edge++) {
172                 vec2d edgevec,checkvec;
173                 fix d;
174
175                 v0 = (vms_vector_array *)&Vertices[vertex_list[facenum*3+edge]];
176                 v1 = (vms_vector_array *)&Vertices[vertex_list[facenum*3+((edge+1)%nv)]];
177
178                 edgevec.i = v1->xyz[i] - v0->xyz[i];
179                 edgevec.j = v1->xyz[j] - v0->xyz[j];
180
181                 checkvec.i = check_i - v0->xyz[i];
182                 checkvec.j = check_j - v0->xyz[j];
183
184                 d = fixmul(checkvec.i,edgevec.j) - fixmul(checkvec.j,edgevec.i);
185
186                 if (d < 0)                              //we are outside of triangle
187                         edgemask |= (1<<edge);
188         }
189
190         return edgemask;
191
192 }
193
194
195 //check if a sphere intersects a face
196 int check_sphere_to_face(vms_vector *pnt, side *s,int facenum,int nv,fix rad,int *vertex_list)
197 {
198         vms_vector checkp=*pnt;
199         uint edgemask;
200
201         //now do 2d check to see if point is in side
202
203         edgemask = check_point_to_face(pnt,s,facenum,nv,vertex_list);
204
205         //we've gone through all the sides, are we inside?
206
207         if (edgemask == 0)
208                 return IT_FACE;
209         else {
210                 vms_vector edgevec,checkvec;            //this time, real 3d vectors
211                 vms_vector closest_point;
212                 fix edgelen,d,dist;
213                 vms_vector *v0,*v1;
214                 int itype;
215                 int edgenum;
216
217                 //get verts for edge we're behind
218
219                 for (edgenum=0;!(edgemask&1);(edgemask>>=1),edgenum++);
220
221                 v0 = &Vertices[vertex_list[facenum*3+edgenum]];
222                 v1 = &Vertices[vertex_list[facenum*3+((edgenum+1)%nv)]];
223
224                 //check if we are touching an edge or point
225
226                 vm_vec_sub(&checkvec,&checkp,v0);
227                 edgelen = vm_vec_normalized_dir(&edgevec,v1,v0);
228                 
229                 //find point dist from planes of ends of edge
230
231                 d = vm_vec_dot(&edgevec,&checkvec);
232
233                 if (d+rad < 0) return IT_NONE;                  //too far behind start point
234
235                 if (d-rad > edgelen) return IT_NONE;    //too far part end point
236
237                 //find closest point on edge to check point
238
239                 itype = IT_POINT;
240
241                 if (d < 0) closest_point = *v0;
242                 else if (d > edgelen) closest_point = *v1;
243                 else {
244                         itype = IT_EDGE;
245
246                         //vm_vec_scale(&edgevec,d);
247                         //vm_vec_add(&closest_point,v0,&edgevec);
248
249                         vm_vec_scale_add(&closest_point,v0,&edgevec,d);
250                 }
251
252                 dist = vm_vec_dist(&checkp,&closest_point);
253
254                 if (dist <= rad)
255                         return (itype==IT_POINT)?IT_NONE:itype;
256                 else
257                         return IT_NONE;
258         }
259
260
261 }
262
263 //returns true if line intersects with face. fills in newp with intersection
264 //point on plane, whether or not line intersects side
265 //facenum determines which of four possible faces we have
266 //note: the seg parm is temporary, until the face itself has a point field
267 int check_line_to_face(vms_vector *newp,vms_vector *p0,vms_vector *p1,segment *seg,int side,int facenum,int nv,fix rad)
268 {
269         vms_vector checkp;
270         int pli;
271         struct side *s=&seg->sides[side];
272         int vertex_list[6];
273         int num_faces;
274         int vertnum;
275         vms_vector norm;
276
277         #ifdef COMPACT_SEGS
278                 get_side_normal(seg, side, facenum, &norm );
279         #else
280                 norm = seg->sides[side].normals[facenum];
281         #endif
282
283         if ((seg-Segments)==-1)
284                 Error("segnum == -1 in check_line_to_face()");
285
286         create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
287
288         //use lowest point number
289         if (num_faces==2) {
290                 vertnum = min(vertex_list[0],vertex_list[2]);
291         }
292         else {
293                 int i;
294                 vertnum = vertex_list[0];
295                 for (i=1;i<4;i++)
296                         if (vertex_list[i] < vertnum)
297                                 vertnum = vertex_list[i];
298         }
299
300         pli = find_plane_line_intersection(newp,&Vertices[vertnum],&norm,p0,p1,rad);
301
302         if (!pli) return IT_NONE;
303
304         checkp = *newp;
305
306         //if rad != 0, project the point down onto the plane of the polygon
307
308         if (rad!=0)
309                 vm_vec_scale_add2(&checkp,&norm,-rad);
310
311         return check_sphere_to_face(&checkp,s,facenum,nv,rad,vertex_list);
312
313 }
314
315 //returns the value of a determinant
316 fix calc_det_value(vms_matrix *det)
317 {
318         return  fixmul(det->rvec.x,fixmul(det->uvec.y,det->fvec.z)) -
319                                 fixmul(det->rvec.x,fixmul(det->uvec.z,det->fvec.y)) -
320                                 fixmul(det->rvec.y,fixmul(det->uvec.x,det->fvec.z)) +
321                                 fixmul(det->rvec.y,fixmul(det->uvec.z,det->fvec.x)) +
322                                 fixmul(det->rvec.z,fixmul(det->uvec.x,det->fvec.y)) -
323                                 fixmul(det->rvec.z,fixmul(det->uvec.y,det->fvec.x));
324 }
325
326 //computes the parameters of closest approach of two lines 
327 //fill in two parameters, t0 & t1.  returns 0 if lines are parallel, else 1
328 int check_line_to_line(fix *t1,fix *t2,vms_vector *p1,vms_vector *v1,vms_vector *p2,vms_vector *v2)
329 {
330         vms_matrix det;
331         fix d,cross_mag2;               //mag squared cross product
332
333         vm_vec_sub(&det.rvec,p2,p1);
334         vm_vec_cross(&det.fvec,v1,v2);
335         cross_mag2 = vm_vec_dot(&det.fvec,&det.fvec);
336
337         if (cross_mag2 == 0)
338                 return 0;                       //lines are parallel
339
340         det.uvec = *v2;
341         d = calc_det_value(&det);
342         if (oflow_check(d,cross_mag2))
343                 return 0;
344         else
345                 *t1 = fixdiv(d,cross_mag2);
346
347         det.uvec = *v1;
348         d = calc_det_value(&det);
349         if (oflow_check(d,cross_mag2))
350                 return 0;
351         else
352                 *t2 = fixdiv(d,cross_mag2);
353
354         return 1;               //found point
355 }
356
357 #ifdef NEW_FVI_STUFF
358 int disable_new_fvi_stuff=0;
359 #else
360 #define disable_new_fvi_stuff 1
361 #endif
362
363 //this version is for when the start and end positions both poke through
364 //the plane of a side.  In this case, we must do checks against the edge
365 //of faces
366 int special_check_line_to_face(vms_vector *newp,vms_vector *p0,vms_vector *p1,segment *seg,int side,int facenum,int nv,fix rad)
367 {
368         vms_vector move_vec;
369         fix edge_t,move_t,edge_t2,move_t2,closest_dist;
370         fix edge_len,move_len;
371         int vertex_list[6];
372         int num_faces,edgenum;
373         uint edgemask;
374         vms_vector *edge_v0,*edge_v1,edge_vec;
375         struct side *s=&seg->sides[side];
376         vms_vector closest_point_edge,closest_point_move;
377
378         if (disable_new_fvi_stuff)
379                 return check_line_to_face(newp,p0,p1,seg,side,facenum,nv,rad);
380
381         //calc some basic stuff
382  
383         if ((seg-Segments)==-1)
384                 Error("segnum == -1 in special_check_line_to_face()");
385
386         create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
387         vm_vec_sub(&move_vec,p1,p0);
388
389         //figure out which edge(s) to check against
390
391         edgemask = check_point_to_face(p0,s,facenum,nv,vertex_list);
392
393         if (edgemask == 0)
394                 return check_line_to_face(newp,p0,p1,seg,side,facenum,nv,rad);
395
396         for (edgenum=0;!(edgemask&1);edgemask>>=1,edgenum++);
397
398         edge_v0 = &Vertices[vertex_list[facenum*3+edgenum]];
399         edge_v1 = &Vertices[vertex_list[facenum*3+((edgenum+1)%nv)]];
400
401         vm_vec_sub(&edge_vec,edge_v1,edge_v0);
402
403         //is the start point already touching the edge?
404
405         //??
406
407         //first, find point of closest approach of vec & edge
408
409         edge_len = vm_vec_normalize(&edge_vec);
410         move_len = vm_vec_normalize(&move_vec);
411
412         check_line_to_line(&edge_t,&move_t,edge_v0,&edge_vec,p0,&move_vec);
413
414         //make sure t values are in valid range
415
416         if (move_t<0 || move_t>move_len+rad)
417                 return IT_NONE;
418
419         if (move_t > move_len)
420                 move_t2 = move_len;
421         else
422                 move_t2 = move_t;
423
424         if (edge_t < 0)         //saturate at points
425                 edge_t2 = 0;
426         else
427                 edge_t2 = edge_t;
428         
429         if (edge_t2 > edge_len)         //saturate at points
430                 edge_t2 = edge_len;
431         
432         //now, edge_t & move_t determine closest points.  calculate the points.
433
434         vm_vec_scale_add(&closest_point_edge,edge_v0,&edge_vec,edge_t2);
435         vm_vec_scale_add(&closest_point_move,p0,&move_vec,move_t2);
436
437         //find dist between closest points
438
439         closest_dist = vm_vec_dist(&closest_point_edge,&closest_point_move);
440
441         //could we hit with this dist?
442
443         //note massive tolerance here
444 //      if (closest_dist < (rad*18)/20) {               //we hit.  figure out where
445         if (closest_dist < (rad*15)/20) {               //we hit.  figure out where
446
447                 //now figure out where we hit
448
449                 vm_vec_scale_add(newp,p0,&move_vec,move_t-rad);
450
451                 return IT_EDGE;
452
453         }
454         else
455                 return IT_NONE;                 //no hit
456
457 }
458
459 //maybe this routine should just return the distance and let the caller
460 //decide it it's close enough to hit
461 //determine if and where a vector intersects with a sphere
462 //vector defined by p0,p1 
463 //returns dist if intersects, and fills in intp
464 //else returns 0
465 int check_vector_to_sphere_1(vms_vector *intp,vms_vector *p0,vms_vector *p1,vms_vector *sphere_pos,fix sphere_rad)
466 {
467         vms_vector d,dn,w,closest_point;
468         fix mag_d,dist,w_dist,int_dist;
469
470         //this routine could be optimized if it's taking too much time!
471
472         vm_vec_sub(&d,p1,p0);
473         vm_vec_sub(&w,sphere_pos,p0);
474
475         mag_d = vm_vec_copy_normalize(&dn,&d);
476
477         if (mag_d == 0) {
478                 int_dist = vm_vec_mag(&w);
479                 *intp = *p0;
480                 return (int_dist<sphere_rad)?int_dist:0;
481         }
482
483         w_dist = vm_vec_dot(&dn,&w);
484
485         if (w_dist < 0)         //moving away from object
486                  return 0;
487
488         if (w_dist > mag_d+sphere_rad)
489                 return 0;               //cannot hit
490
491         vm_vec_scale_add(&closest_point,p0,&dn,w_dist);
492
493         dist = vm_vec_dist(&closest_point,sphere_pos);
494
495         if (dist < sphere_rad) {
496                 fix dist2,rad2,shorten;
497
498                 dist2 = fixmul(dist,dist);
499                 rad2 = fixmul(sphere_rad,sphere_rad);
500
501                 shorten = fix_sqrt(rad2 - dist2);
502
503                 int_dist = w_dist-shorten;
504
505                 if (int_dist > mag_d || int_dist < 0) {
506                         //past one or the other end of vector, which means we're inside
507
508                         *intp = *p0;            //don't move at all
509                         return 1;
510                 }
511
512                 vm_vec_scale_add(intp,p0,&dn,int_dist);         //calc intersection point
513
514 //              {
515 //                      fix dd = vm_vec_dist(intp,sphere_pos);
516 //                      Assert(dd == sphere_rad);
517 //                      mprintf(0,"dd=%x, rad=%x, delta=%x\n",dd,sphere_rad,dd-sphere_rad);
518 //              }
519
520
521                 return int_dist;
522         }
523         else
524                 return 0;
525 }
526
527 /*
528 //$$fix get_sphere_int_dist(vms_vector *w,fix dist,fix rad);
529 //$$
530 //$$#pragma aux get_sphere_int_dist parm [esi] [ebx] [ecx] value [eax] modify exact [eax ebx ecx edx] = \
531 //$$    "mov eax,ebx"           \
532 //$$    "imul eax"                      \
533 //$$                                                    \
534 //$$    "mov ebx,eax"           \
535 //$$   "mov eax,ecx"            \
536 //$$    "mov ecx,edx"           \
537 //$$                                                    \
538 //$$    "imul eax"                      \
539 //$$                                                    \
540 //$$    "sub eax,ebx"           \
541 //$$    "sbb edx,ecx"           \
542 //$$                                                    \
543 //$$    "call quad_sqrt"        \
544 //$$                                                    \
545 //$$    "push eax"                      \
546 //$$                                                    \
547 //$$    "push ebx"                      \
548 //$$    "push ecx"                      \
549 //$$                                                    \
550 //$$    "mov eax,[esi]" \
551 //$$    "imul eax"                      \
552 //$$    "mov ebx,eax"           \
553 //$$    "mov ecx,edx"           \
554 //$$    "mov eax,4[esi]"        \
555 //$$    "imul eax"                      \
556 //$$    "add ebx,eax"           \
557 //$$    "adc ecx,edx"           \
558 //$$    "mov eax,8[esi]"        \
559 //$$    "imul eax"                      \
560 //$$    "add eax,ebx"           \
561 //$$    "adc edx,ecx"           \
562 //$$                                                    \
563 //$$    "pop ecx"                       \
564 //$$    "pop ebx"                       \
565 //$$                                                    \
566 //$$    "sub eax,ebx"           \
567 //$$    "sbb edx,ecx"           \
568 //$$                                                    \
569 //$$    "call quad_sqrt"        \
570 //$$                                                    \
571 //$$    "pop ebx"                       \
572 //$$    "sub eax,ebx";
573 //$$
574 //$$
575 //$$//determine if and where a vector intersects with a sphere
576 //$$//vector defined by p0,p1 
577 //$$//returns dist if intersects, and fills in intp. if no intersect, return 0
578 //$$fix check_vector_to_sphere_2(vms_vector *intp,vms_vector *p0,vms_vector *p1,vms_vector *sphere_pos,fix sphere_rad)
579 //$${
580 //$$    vms_vector d,w,c;
581 //$$    fix mag_d,dist,mag_c,mag_w;
582 //$$    vms_vector wn,dn;
583 //$$
584 //$$    vm_vec_sub(&d,p1,p0);
585 //$$    vm_vec_sub(&w,sphere_pos,p0);
586 //$$
587 //$$    //wn = w; mag_w = vm_vec_normalize(&wn);
588 //$$    //dn = d; mag_d = vm_vec_normalize(&dn);
589 //$$
590 //$$    mag_w = vm_vec_copy_normalize(&wn,&w);
591 //$$    mag_d = vm_vec_copy_normalize(&dn,&d);
592 //$$
593 //$$    //vm_vec_cross(&c,&w,&d);
594 //$$    vm_vec_cross(&c,&wn,&dn);
595 //$$
596 //$$    mag_c = vm_vec_mag(&c);
597 //$$    //mag_d = vm_vec_mag(&d);
598 //$$
599 //$$    //dist = fixdiv(mag_c,mag_d);
600 //$$
601 //$$dist = fixmul(mag_c,mag_w);
602 //$$
603 //$$    if (dist < sphere_rad) {        //we intersect.  find point of intersection
604 //$$            fix int_dist;                   //length of vector to intersection point
605 //$$            fix k;                                  //portion of p0p1 we want
606 //$$//@@                fix dist2,rad2,shorten,mag_w2;
607 //$$
608 //$$//@@                mag_w2 = vm_vec_dot(&w,&w);     //the square of the magnitude
609 //$$//@@                //WHAT ABOUT OVERFLOW???
610 //$$//@@                dist2 = fixmul(dist,dist);
611 //$$//@@                rad2 = fixmul(sphere_rad,sphere_rad);
612 //$$//@@                shorten = fix_sqrt(rad2 - dist2);
613 //$$//@@                int_dist = fix_sqrt(mag_w2 - dist2) - shorten;
614 //$$
615 //$$            int_dist = get_sphere_int_dist(&w,dist,sphere_rad);
616 //$$
617 //$$if (labs(int_dist) > mag_d) //I don't know why this would happen
618 //$$    if (int_dist > 0)
619 //$$            k = f1_0;
620 //$$    else
621 //$$            k = -f1_0;
622 //$$else
623 //$$            k = fixdiv(int_dist,mag_d);
624 //$$
625 //$$//          vm_vec_scale(&d,k);                     //vec from p0 to intersection point
626 //$$//          vm_vec_add(intp,p0,&d);         //intersection point
627 //$$            vm_vec_scale_add(intp,p0,&d,k); //calc new intersection point
628 //$$
629 //$$            return int_dist;
630 //$$    }
631 //$$    else
632 //$$            return 0;       //no intersection
633 //$$}
634 */
635
636 //determine if a vector intersects with an object
637 //if no intersects, returns 0, else fills in intp and returns dist
638 fix check_vector_to_object(vms_vector *intp,vms_vector *p0,vms_vector *p1,fix rad,object *obj,object *otherobj)
639 {
640         fix size = obj->size;
641
642         if (obj->type == OBJ_ROBOT && Robot_info[obj->id].attack_type)
643                 size = (size*3)/4;
644
645         //if obj is player, and bumping into other player or a weapon of another coop player, reduce radius
646         if (obj->type == OBJ_PLAYER && 
647                         ((otherobj->type == OBJ_PLAYER) ||
648                         ((Game_mode&GM_MULTI_COOP) && otherobj->type == OBJ_WEAPON && otherobj->ctype.laser_info.parent_type == OBJ_PLAYER)))
649                 size = size/2;
650
651         return check_vector_to_sphere_1(intp,p0,p1,&obj->pos,size+rad);
652
653 }
654
655
656 #define MAX_SEGS_VISITED 100
657 int n_segs_visited;
658 short segs_visited[MAX_SEGS_VISITED];
659
660 int fvi_nest_count;
661
662 //these vars are used to pass vars from fvi_sub() to find_vector_intersection()
663 int fvi_hit_object;     // object number of object hit in last find_vector_intersection call.
664 int fvi_hit_seg;                // what segment the hit point is in
665 int fvi_hit_side;               // what side was hit
666 int fvi_hit_side_seg;// what seg the hitside is in
667 vms_vector wall_norm;   //ptr to surface normal of hit wall
668 int fvi_hit_seg2;               // what segment the hit point is in
669
670 int fvi_sub(vms_vector *intp,int *ints,vms_vector *p0,int startseg,vms_vector *p1,fix rad,short thisobjnum,int *ignore_obj_list,int flags,int *seglist,int *n_segs,int entry_seg);
671
672 //What the hell is fvi_hit_seg for???
673
674 //Find out if a vector intersects with anything.
675 //Fills in hit_data, an fvi_info structure (see header file).
676 //Parms:
677 //  p0 & startseg       describe the start of the vector
678 //  p1                                  the end of the vector
679 //  rad                                         the radius of the cylinder
680 //  thisobjnum          used to prevent an object with colliding with itself
681 //  ingore_obj                  ignore collisions with this object
682 //  check_obj_flag      determines whether collisions with objects are checked
683 //Returns the hit_data->hit_type
684 int find_vector_intersection(fvi_query *fq,fvi_info *hit_data)
685 {
686         int hit_type,hit_seg,hit_seg2;
687         vms_vector hit_pnt;
688         int i;
689
690         Assert(fq->ignore_obj_list != (int *)(-1));
691         Assert((fq->startseg <= Highest_segment_index) && (fq->startseg >= 0));
692
693         fvi_hit_seg = -1;
694         fvi_hit_side = -1;
695
696         fvi_hit_object = -1;
697
698         //check to make sure start point is in seg its supposed to be in
699         //Assert(check_point_in_seg(p0,startseg,0).centermask==0);      //start point not in seg
700
701         // Viewer is not in segment as claimed, so say there is no hit.
702         if(!(get_seg_masks(fq->p0,fq->startseg,0).centermask==0)) {
703
704                 hit_data->hit_type = HIT_BAD_P0;
705                 hit_data->hit_pnt = *fq->p0;
706                 hit_data->hit_seg = fq->startseg;
707                 hit_data->hit_side = hit_data->hit_object = 0;
708                 hit_data->hit_side_seg = -1;
709
710                 return hit_data->hit_type;
711         }
712
713         segs_visited[0] = fq->startseg;
714
715         n_segs_visited=1;
716
717         fvi_nest_count = 0;
718
719         hit_seg2 = fvi_hit_seg2 = -1;
720
721         hit_type = fvi_sub(&hit_pnt,&hit_seg2,fq->p0,fq->startseg,fq->p1,fq->rad,fq->thisobjnum,fq->ignore_obj_list,fq->flags,hit_data->seglist,&hit_data->n_segs,-2);
722         //!!hit_seg = find_point_seg(&hit_pnt,fq->startseg);
723         if (hit_seg2!=-1 && !get_seg_masks(&hit_pnt,hit_seg2,0).centermask)
724                 hit_seg = hit_seg2;
725         else
726                 hit_seg = find_point_seg(&hit_pnt,fq->startseg);
727
728 //MATT: TAKE OUT THIS HACK AND FIX THE BUGS!
729         if (hit_type == HIT_WALL && hit_seg==-1)
730                 if (fvi_hit_seg2!=-1 && get_seg_masks(&hit_pnt,fvi_hit_seg2,0).centermask==0)
731                         hit_seg = fvi_hit_seg2;
732
733         if (hit_seg == -1) {
734                 int new_hit_type;
735                 int new_hit_seg2=-1;
736                 vms_vector new_hit_pnt;
737
738                 //because of code that deal with object with non-zero radius has
739                 //problems, try using zero radius and see if we hit a wall
740
741                 new_hit_type = fvi_sub(&new_hit_pnt,&new_hit_seg2,fq->p0,fq->startseg,fq->p1,0,fq->thisobjnum,fq->ignore_obj_list,fq->flags,hit_data->seglist,&hit_data->n_segs,-2);
742
743                 if (new_hit_seg2 != -1) {
744                         hit_seg = new_hit_seg2;
745                         hit_pnt = new_hit_pnt;
746                 }
747         }
748
749
750 if (hit_seg!=-1 && fq->flags&FQ_GET_SEGLIST)
751         if (hit_seg != hit_data->seglist[hit_data->n_segs-1] && hit_data->n_segs<MAX_FVI_SEGS-1)
752                 hit_data->seglist[hit_data->n_segs++] = hit_seg;
753
754 if (hit_seg!=-1 && fq->flags&FQ_GET_SEGLIST)
755         for (i=0;i<hit_data->n_segs && i<MAX_FVI_SEGS-1;i++)
756                 if (hit_data->seglist[i] == hit_seg) {
757                         hit_data->n_segs = i+1;
758                         break;
759                 }
760
761 //I'm sorry to say that sometimes the seglist isn't correct.  I did my
762 //best.  Really.
763
764
765 //{     //verify hit list
766 //
767 //      int i,ch;
768 //
769 //      Assert(hit_data->seglist[0] == startseg);
770 //
771 //      for (i=0;i<hit_data->n_segs-1;i++) {
772 //              for (ch=0;ch<6;ch++)
773 //                      if (Segments[hit_data->seglist[i]].children[ch] == hit_data->seglist[i+1])
774 //                              break;
775 //              Assert(ch<6);
776 //      }
777 //
778 //      Assert(hit_data->seglist[hit_data->n_segs-1] == hit_seg);
779 //}
780         
781
782 //MATT: PUT THESE ASSERTS BACK IN AND FIX THE BUGS!
783 //!!    Assert(hit_seg!=-1);
784 //!!    Assert(!((hit_type==HIT_WALL) && (hit_seg == -1)));
785         //When this assert happens, get Matt.  Matt:  Look at hit_seg2 & 
786         //fvi_hit_seg.  At least one of these should be set.  Why didn't 
787         //find_new_seg() find something?
788
789 //      Assert(fvi_hit_seg==-1 || fvi_hit_seg == hit_seg);
790
791         Assert(!(hit_type==HIT_OBJECT && fvi_hit_object==-1));
792
793         hit_data->hit_type              = hit_type;
794         hit_data->hit_pnt               = hit_pnt;
795         hit_data->hit_seg               = hit_seg;
796         hit_data->hit_side              = fvi_hit_side; //looks at global
797         hit_data->hit_side_seg  = fvi_hit_side_seg;     //looks at global
798         hit_data->hit_object            = fvi_hit_object;       //looks at global
799         hit_data->hit_wallnorm  = wall_norm;            //looks at global
800
801 //      if(hit_seg!=-1 && get_seg_masks(&hit_data->hit_pnt,hit_data->hit_seg,0).centermask!=0)
802 //              Int3();
803
804         return hit_type;
805
806 }
807
808 //--unused-- fix check_dist(vms_vector *v0,vms_vector *v1)
809 //--unused-- {
810 //--unused--    return vm_vec_dist(v0,v1);
811 //--unused-- }
812
813 int obj_in_list(int objnum,int *obj_list)
814 {
815         int t;
816
817         while ((t=*obj_list)!=-1 && t!=objnum) obj_list++;
818
819         return (t==objnum);
820
821 }
822
823 int check_trans_wall(vms_vector *pnt,segment *seg,int sidenum,int facenum);
824
825 int fvi_sub(vms_vector *intp,int *ints,vms_vector *p0,int startseg,vms_vector *p1,fix rad,short thisobjnum,int *ignore_obj_list,int flags,int *seglist,int *n_segs,int entry_seg)
826 {
827         segment *seg;                           //the segment we're looking at
828         int startmask,endmask;  //mask of faces
829         //@@int sidemask;                               //mask of sides - can be on back of face but not side
830         int centermask;                 //where the center point is
831         int objnum;
832         segmasks masks;
833         vms_vector hit_point,closest_hit_point;         //where we hit
834         fix d,closest_d=0x7fffffff;                                     //distance to hit point
835         int hit_type=HIT_NONE;                                                  //what sort of hit
836         int hit_seg=-1;
837         int hit_none_seg=-1;
838         int hit_none_n_segs=0;
839         int hit_none_seglist[MAX_FVI_SEGS];
840         int cur_nest_level = fvi_nest_count;
841
842         //fvi_hit_object = -1;
843
844         if (flags&FQ_GET_SEGLIST)
845                 *seglist = startseg; 
846         *n_segs=1;
847
848         seg = &Segments[startseg];
849
850         fvi_nest_count++;
851
852         //first, see if vector hit any objects in this segment
853         if (flags & FQ_CHECK_OBJS)
854                 for (objnum=seg->objects;objnum!=-1;objnum=Objects[objnum].next)
855                         if (    !(Objects[objnum].flags & OF_SHOULD_BE_DEAD) &&
856                                         !(thisobjnum == objnum ) &&
857                                         (ignore_obj_list==NULL || !obj_in_list(objnum,ignore_obj_list)) &&
858                                         !laser_are_related( objnum, thisobjnum ) &&
859                                         !((thisobjnum  > -1)    &&
860                                                 (CollisionResult[Objects[thisobjnum].type][Objects[objnum].type] == RESULT_NOTHING ) &&
861                                                 (CollisionResult[Objects[objnum].type][Objects[thisobjnum].type] == RESULT_NOTHING ))) {
862                                 int fudged_rad = rad;
863
864                                 //      If this is a powerup, don't do collision if flag FQ_IGNORE_POWERUPS is set
865                                 if (Objects[objnum].type == OBJ_POWERUP)
866                                         if (flags & FQ_IGNORE_POWERUPS)
867                                                 continue;
868
869                                 //      If this is a robot:robot collision, only do it if both of them have attack_type != 0 (eg, green guy)
870                                 if (Objects[thisobjnum].type == OBJ_ROBOT)
871                                         if (Objects[objnum].type == OBJ_ROBOT)
872                                                 // -- MK: 11/18/95, 4claws glomming together...this is easy.  -- if (!(Robot_info[Objects[objnum].id].attack_type && Robot_info[Objects[thisobjnum].id].attack_type))
873                                                         continue;
874
875                                 if (Objects[thisobjnum].type == OBJ_ROBOT && Robot_info[Objects[thisobjnum].id].attack_type)
876                                         fudged_rad = (rad*3)/4;
877
878                                 //if obj is player, and bumping into other player or a weapon of another coop player, reduce radius
879                                 if (Objects[thisobjnum].type == OBJ_PLAYER && 
880                                                 ((Objects[objnum].type == OBJ_PLAYER) ||
881                                                 ((Game_mode&GM_MULTI_COOP) &&  Objects[objnum].type == OBJ_WEAPON && Objects[objnum].ctype.laser_info.parent_type == OBJ_PLAYER)))
882                                         fudged_rad = rad/2;     //(rad*3)/4;
883
884                                 d = check_vector_to_object(&hit_point,p0,p1,fudged_rad,&Objects[objnum],&Objects[thisobjnum]);
885
886                                 if (d)          //we have intersection
887                                         if (d < closest_d) {
888                                                 fvi_hit_object = objnum; 
889                                                 Assert(fvi_hit_object!=-1);
890                                                 closest_d = d; 
891                                                 closest_hit_point = hit_point; 
892                                                 hit_type=HIT_OBJECT;
893                                         }
894                         }
895
896         if (    (thisobjnum > -1 ) && (CollisionResult[Objects[thisobjnum].type][OBJ_WALL] == RESULT_NOTHING ) )
897                 rad = 0;                //HACK - ignore when edges hit walls
898
899         //now, check segment walls
900
901         startmask = get_seg_masks(p0,startseg,rad).facemask;
902
903         masks = get_seg_masks(p1,startseg,rad);    //on back of which faces?
904         endmask = masks.facemask;
905         //@@sidemask = masks.sidemask;
906         centermask = masks.centermask;
907
908         if (centermask==0) hit_none_seg = startseg;
909
910         if (endmask != 0) {                             //on the back of at least one face
911
912                 int side,bit,face;
913
914                 //for each face we are on the back of, check if intersected
915
916                 for (side=0,bit=1;side<6 && endmask>=bit;side++) {
917                         int num_faces;
918                         num_faces = get_num_faces(&seg->sides[side]);
919
920                         if (num_faces == 0)
921                                 num_faces = 1;
922
923                         // commented out by mk on 02/13/94:: if ((num_faces=seg->sides[side].num_faces)==0) num_faces=1;
924
925                         for (face=0;face<2;face++,bit<<=1) {
926
927                                 if (endmask & bit) {            //on the back of this face
928                                         int face_hit_type;      //in what way did we hit the face?
929
930
931                                         if (seg->children[side] == entry_seg)
932                                                 continue;               //don't go back through entry side
933
934                                         //did we go through this wall/door?
935
936                                         //#ifdef NEW_FVI_STUFF
937                                         if (startmask & bit)            //start was also though.  Do extra check
938                                                 face_hit_type = special_check_line_to_face( &hit_point,
939                                                                                 p0,p1,seg,side,
940                                                                                 face,
941                                                                                 ((num_faces==1)?4:3),rad);
942                                         else
943                                         //#endif
944                                                 //NOTE LINK TO ABOVE!!
945                                                 face_hit_type = check_line_to_face( &hit_point,
946                                                                                 p0,p1,seg,side,
947                                                                                 face,
948                                                                                 ((num_faces==1)?4:3),rad);
949
950         
951                                         if (face_hit_type) {            //through this wall/door
952                                                 int wid_flag;
953
954                                                 //if what we have hit is a door, check the adjoining seg
955
956                                                 if ( (thisobjnum == Players[Player_num].objnum) && (Physics_cheat_flag==0xBADA55) )     {
957                                                         wid_flag = WALL_IS_DOORWAY(seg, side);
958                                                         if (seg->children[side] >= 0 ) 
959                                                                 wid_flag |= WID_FLY_FLAG;
960                                                 } else {
961                                                         wid_flag = WALL_IS_DOORWAY(seg, side);
962                                                 }
963
964                                                 if ((wid_flag & WID_FLY_FLAG) ||
965                                                         (((wid_flag & WID_RENDER_FLAG) && (wid_flag & WID_RENDPAST_FLAG)) && 
966                                                                 ((flags & FQ_TRANSWALL) || (flags & FQ_TRANSPOINT && check_trans_wall(&hit_point,seg,side,face))))) {
967
968                                                         int newsegnum;
969                                                         vms_vector sub_hit_point;
970                                                         int sub_hit_type,sub_hit_seg;
971                                                         vms_vector save_wall_norm = wall_norm;
972                                                         int save_hit_objnum=fvi_hit_object;
973                                                         int i;
974
975                                                         //do the check recursively on the next seg.
976
977                                                         newsegnum = seg->children[side];
978
979                                                         for (i=0;i<n_segs_visited && newsegnum!=segs_visited[i];i++);
980
981                                                         if (i==n_segs_visited) {                //haven't visited here yet
982                                                                 int temp_seglist[MAX_FVI_SEGS],temp_n_segs;
983                                                                 
984                                                                 segs_visited[n_segs_visited++] = newsegnum;
985
986                                                                 if (n_segs_visited >= MAX_SEGS_VISITED)
987                                                                         goto quit_looking;              //we've looked a long time, so give up
988
989                                                                 sub_hit_type = fvi_sub(&sub_hit_point,&sub_hit_seg,p0,newsegnum,p1,rad,thisobjnum,ignore_obj_list,flags,temp_seglist,&temp_n_segs,startseg);
990
991                                                                 if (sub_hit_type != HIT_NONE) {
992
993                                                                         d = vm_vec_dist(&sub_hit_point,p0);
994
995                                                                         if (d < closest_d) {
996
997                                                                                 closest_d = d; 
998                                                                                 closest_hit_point = sub_hit_point;
999                                                                                 hit_type = sub_hit_type;
1000                                                                                 if (sub_hit_seg!=-1) hit_seg = sub_hit_seg;
1001
1002                                                                                 //copy seglist
1003                                                                                 if (flags&FQ_GET_SEGLIST) {
1004                                                                                         int ii;
1005                                                                                         for (ii=0;i<temp_n_segs && *n_segs<MAX_FVI_SEGS-1;)
1006                                                                                                 seglist[(*n_segs)++] = temp_seglist[ii++];
1007                                                                                 }
1008
1009                                                                                 Assert(*n_segs < MAX_FVI_SEGS);
1010                                                                         }
1011                                                                         else {
1012                                                                                 wall_norm = save_wall_norm;     //global could be trashed
1013                                                                                 fvi_hit_object = save_hit_objnum;
1014                                                                         }
1015
1016                                                                 }
1017                                                                 else {
1018                                                                         wall_norm = save_wall_norm;     //global could be trashed
1019                                                                         if (sub_hit_seg!=-1) hit_none_seg = sub_hit_seg;
1020                                                                         //copy seglist
1021                                                                         if (flags&FQ_GET_SEGLIST) {
1022                                                                                 int ii;
1023                                                                                 for (ii=0;ii<temp_n_segs && ii<MAX_FVI_SEGS-1;ii++)
1024                                                                                         hit_none_seglist[ii] = temp_seglist[ii];
1025                                                                         }
1026                                                                         hit_none_n_segs = temp_n_segs;
1027                                                                 }
1028                                                         }
1029                                                 }
1030                                                 else {          //a wall
1031                                                                                                                                 
1032                                                                 //is this the closest hit?
1033         
1034                                                                 d = vm_vec_dist(&hit_point,p0);
1035         
1036                                                                 if (d < closest_d) {
1037                                                                         closest_d = d; 
1038                                                                         closest_hit_point = hit_point;
1039                                                                         hit_type = HIT_WALL;
1040                                                                         
1041                                                                         #ifdef COMPACT_SEGS
1042                                                                                 get_side_normal(seg, side, face, &wall_norm );
1043                                                                         #else
1044                                                                                 wall_norm = seg->sides[side].normals[face];     
1045                                                                         #endif
1046                                                                         
1047         
1048                                                                         if (get_seg_masks(&hit_point,startseg,rad).centermask==0)
1049                                                                                 hit_seg = startseg;             //hit in this segment
1050                                                                         else
1051                                                                                 fvi_hit_seg2 = startseg;
1052
1053                                                                         //@@else         {
1054                                                                         //@@    mprintf( 0, "Warning on line 991 in physics.c\n" );
1055                                                                         //@@    hit_seg = startseg;             //hit in this segment
1056                                                                         //@@    //Int3();
1057                                                                         //@@}
1058
1059                                                                         fvi_hit_seg = hit_seg;
1060                                                                         fvi_hit_side =  side;
1061                                                                         fvi_hit_side_seg = startseg;
1062
1063                                                                 }
1064                                                 }
1065                                         }
1066                                 }
1067                         }
1068                 }
1069         }
1070
1071 //      Assert(centermask==0 || hit_seg!=startseg);
1072
1073 //      Assert(sidemask==0);            //Error("Didn't find side we went though");
1074
1075 quit_looking:
1076         ;
1077
1078         if (hit_type == HIT_NONE) {     //didn't hit anything, return end point
1079                 int i;
1080
1081                 *intp = *p1;
1082                 *ints = hit_none_seg;
1083                 //MATT: MUST FIX THIS!!!!
1084                 //Assert(!centermask);
1085
1086                 if (hit_none_seg!=-1) {                 ///(centermask == 0)
1087                         if (flags&FQ_GET_SEGLIST)
1088                                 //copy seglist
1089                                 for (i=0;i<hit_none_n_segs && *n_segs<MAX_FVI_SEGS-1;)
1090                                         seglist[(*n_segs)++] = hit_none_seglist[i++];
1091                 }
1092                 else
1093                         if (cur_nest_level!=0)
1094                                 *n_segs=0;
1095
1096         }
1097         else {
1098                 *intp = closest_hit_point;
1099                 if (hit_seg==-1)
1100                         if (fvi_hit_seg2 != -1)
1101                                 *ints = fvi_hit_seg2;
1102                         else
1103                                 *ints = hit_none_seg;
1104                 else
1105                         *ints = hit_seg;
1106         }
1107
1108         Assert(!(hit_type==HIT_OBJECT && fvi_hit_object==-1));
1109
1110         return hit_type;
1111
1112 }
1113
1114 /*
1115 //--unused-- //compute the magnitude of a 2d vector
1116 //--unused-- fix mag2d(vec2d *v);
1117 //--unused-- #pragma aux mag2d parm [esi] value [eax] modify exact [eax ebx ecx edx] = \
1118 //--unused--    "mov    eax,[esi]"              \
1119 //--unused--    "imul   eax"                            \
1120 //--unused--    "mov    ebx,eax"                        \
1121 //--unused--    "mov    ecx,edx"                        \
1122 //--unused--    "mov    eax,4[esi]"             \
1123 //--unused--    "imul   eax"                            \
1124 //--unused--    "add    eax,ebx"                        \
1125 //--unused--    "adc    edx,ecx"                        \
1126 //--unused--    "call   quad_sqrt";
1127 */
1128
1129 //--unused-- //returns mag
1130 //--unused-- fix normalize_2d(vec2d *v)
1131 //--unused-- {
1132 //--unused--    fix mag;
1133 //--unused-- 
1134 //--unused--    mag = mag2d(v);
1135 //--unused-- 
1136 //--unused--    v->i = fixdiv(v->i,mag);
1137 //--unused--    v->j = fixdiv(v->j,mag);
1138 //--unused-- 
1139 //--unused--    return mag;
1140 //--unused-- }
1141
1142 #include "textures.h"
1143 #include "texmerge.h"
1144
1145 #define cross(v0,v1) (fixmul((v0)->i,(v1)->j) - fixmul((v0)->j,(v1)->i))
1146
1147 //finds the uv coords of the given point on the given seg & side
1148 //fills in u & v. if l is non-NULL fills it in also
1149 void find_hitpoint_uv(fix *u,fix *v,fix *l,vms_vector *pnt,segment *seg,int sidenum,int facenum)
1150 {
1151         vms_vector_array *pnt_array;
1152         vms_vector_array normal_array;
1153         int segnum = seg-Segments;
1154         int num_faces;
1155         int biggest,ii,jj;
1156         side *side = &seg->sides[sidenum];
1157         int vertex_list[6],vertnum_list[6];
1158         vec2d p1,vec0,vec1,checkp;      //@@,checkv;
1159         uvl uvls[3];
1160         fix k0,k1;
1161         int i;
1162
1163         //mprintf(0,"\ncheck_trans_wall  vec=%x,%x,%x\n",pnt->x,pnt->y,pnt->z);
1164
1165         //do lasers pass through illusory walls?
1166
1167         //when do I return 0 & 1 for non-transparent walls?
1168
1169         if (segnum < 0 || segnum > Highest_segment_index) {
1170                 mprintf((0,"Bad segnum (%d) in find_hitpoint_uv()\n",segnum));
1171                 *u = *v = 0;
1172                 return;
1173         }
1174
1175         if (segnum==-1)
1176                 Error("segnum == -1 in find_hitpoint_uv()");
1177
1178         create_abs_vertex_lists(&num_faces,vertex_list,segnum,sidenum);
1179         create_all_vertnum_lists(&num_faces,vertnum_list,segnum,sidenum);
1180
1181         //now the hard work.
1182
1183         //1. find what plane to project this wall onto to make it a 2d case
1184
1185         #ifdef COMPACT_SEGS
1186                 get_side_normal(seg, sidenum, facenum, (vms_vector *)&normal_array );
1187         #else
1188                 memcpy( &normal_array, &side->normals[facenum], sizeof(vms_vector_array) );
1189         #endif
1190         biggest = 0;
1191
1192         if (abs(normal_array.xyz[1]) > abs(normal_array.xyz[biggest])) biggest = 1;
1193         if (abs(normal_array.xyz[2]) > abs(normal_array.xyz[biggest])) biggest = 2;
1194
1195         if (biggest == 0) ii=1; else ii=0;
1196         if (biggest == 2) jj=1; else jj=2;
1197
1198         //2. compute u,v of intersection point
1199
1200         //vec from 1 -> 0
1201         pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+1]];
1202         p1.i = pnt_array->xyz[ii];
1203         p1.j = pnt_array->xyz[jj];
1204
1205         pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+0]];
1206         vec0.i = pnt_array->xyz[ii] - p1.i;
1207         vec0.j = pnt_array->xyz[jj] - p1.j;
1208
1209         //vec from 1 -> 2
1210         pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+2]];
1211         vec1.i = pnt_array->xyz[ii] - p1.i;
1212         vec1.j = pnt_array->xyz[jj] - p1.j;
1213
1214         //vec from 1 -> checkpoint
1215         pnt_array = (vms_vector_array *)pnt;
1216         checkp.i = pnt_array->xyz[ii];
1217         checkp.j = pnt_array->xyz[jj];
1218
1219         //@@checkv.i = checkp.i - p1.i;
1220         //@@checkv.j = checkp.j - p1.j;
1221
1222         //mprintf(0," vec0   = %x,%x  ",vec0.i,vec0.j);
1223         //mprintf(0," vec1   = %x,%x  ",vec1.i,vec1.j);
1224         //mprintf(0," checkv = %x,%x\n",checkv.i,checkv.j);
1225
1226         k1 = -fixdiv(cross(&checkp,&vec0) + cross(&vec0,&p1),cross(&vec0,&vec1));
1227         if (abs(vec0.i) > abs(vec0.j))
1228                 k0 = fixdiv(fixmul(-k1,vec1.i) + checkp.i - p1.i,vec0.i);
1229         else
1230                 k0 = fixdiv(fixmul(-k1,vec1.j) + checkp.j - p1.j,vec0.j);
1231
1232         //mprintf(0," k0,k1  = %x,%x\n",k0,k1);
1233
1234         for (i=0;i<3;i++)
1235                 uvls[i] = side->uvls[vertnum_list[facenum*3+i]];
1236
1237         *u = uvls[1].u + fixmul( k0,uvls[0].u - uvls[1].u) + fixmul(k1,uvls[2].u - uvls[1].u);
1238         *v = uvls[1].v + fixmul( k0,uvls[0].v - uvls[1].v) + fixmul(k1,uvls[2].v - uvls[1].v);
1239
1240         if (l)
1241                 *l = uvls[1].l + fixmul( k0,uvls[0].l - uvls[1].l) + fixmul(k1,uvls[2].l - uvls[1].l);
1242
1243         //mprintf(0," u,v    = %x,%x\n",*u,*v);
1244 }
1245
1246 //check if a particular point on a wall is a transparent pixel
1247 //returns 1 if can pass though the wall, else 0
1248 int check_trans_wall(vms_vector *pnt,segment *seg,int sidenum,int facenum)
1249 {
1250         grs_bitmap *bm;
1251         side *side = &seg->sides[sidenum];
1252         int bmx,bmy;
1253         fix u,v;
1254
1255 //      Assert(WALL_IS_DOORWAY(seg,sidenum) == WID_TRANSPARENT_WALL);
1256
1257         find_hitpoint_uv(&u,&v,NULL,pnt,seg,sidenum,facenum);   //      Don't compute light value.
1258
1259         if (side->tmap_num2 != 0)       {
1260                 bm = texmerge_get_cached_bitmap( side->tmap_num, side->tmap_num2 );
1261         } else {
1262                 bm = &GameBitmaps[Textures[side->tmap_num].index];
1263                 PIGGY_PAGE_IN( Textures[side->tmap_num] );
1264         }
1265
1266         if (bm->bm_flags & BM_FLAG_RLE)
1267                 bm = rle_expand_texture(bm);
1268
1269         bmx = ((unsigned) f2i(u*bm->bm_w)) % bm->bm_w;
1270         bmy = ((unsigned) f2i(v*bm->bm_h)) % bm->bm_h;
1271
1272 //note: the line above had -v, but that was wrong, so I changed it.  if 
1273 //something doesn't work, and you want to make it negative again, you 
1274 //should figure out what's going on.
1275
1276         //mprintf(0," bmx,y  = %d,%d, color=%x\n",bmx,bmy,bm->bm_data[bmy*64+bmx]);
1277
1278         return (bm->bm_data[bmy*bm->bm_w+bmx] == TRANSPARENCY_COLOR);
1279 }
1280
1281 //new function for Mike
1282 //note: n_segs_visited must be set to zero before this is called
1283 int sphere_intersects_wall(vms_vector *pnt,int segnum,fix rad)
1284 {
1285         int facemask;
1286         segment *seg;
1287
1288         segs_visited[n_segs_visited++] = segnum;
1289
1290         facemask = get_seg_masks(pnt,segnum,rad).facemask;
1291
1292         seg = &Segments[segnum];
1293
1294         if (facemask != 0) {                            //on the back of at least one face
1295
1296                 int side,bit,face;
1297
1298                 //for each face we are on the back of, check if intersected
1299
1300                 for (side=0,bit=1;side<6 && facemask>=bit;side++) {
1301
1302                         for (face=0;face<2;face++,bit<<=1) {
1303
1304                                 if (facemask & bit) {            //on the back of this face
1305                                         int face_hit_type;      //in what way did we hit the face?
1306                                         int num_faces,vertex_list[6];
1307
1308                                         //did we go through this wall/door?
1309
1310                                         if ((seg-Segments)==-1)
1311                                                 Error("segnum == -1 in sphere_intersects_wall()");
1312
1313                                         create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
1314
1315                                         face_hit_type = check_sphere_to_face( pnt,&seg->sides[side],
1316                                                                                 face,((num_faces==1)?4:3),rad,vertex_list);
1317
1318                                         if (face_hit_type) {            //through this wall/door
1319                                                 int child,i;
1320
1321                                                 //if what we have hit is a door, check the adjoining seg
1322
1323                                                 child = seg->children[side];
1324
1325                                                 for (i=0;i<n_segs_visited && child!=segs_visited[i];i++);
1326
1327                                                 if (i==n_segs_visited) {                //haven't visited here yet
1328
1329                                                         if (!IS_CHILD(child))
1330                                                                 return 1;
1331                                                         else {
1332
1333                                                                 if (sphere_intersects_wall(pnt,child,rad))
1334                                                                         return 1;
1335                                                         }
1336                                                 }
1337                                         }
1338                                 }
1339                         }
1340                 }
1341         }
1342
1343         return 0;
1344 }
1345
1346 //Returns true if the object is through any walls
1347 int object_intersects_wall(object *objp)
1348 {
1349         n_segs_visited = 0;
1350
1351         return sphere_intersects_wall(&objp->pos,objp->segnum,objp->size);
1352 }
1353
1354