1 /* $Id: fvi.c,v 1.3 2003-10-10 09:36:35 btb Exp $ */
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17 * New home for find_vector_intersection()
20 * Revision 1.7 1995/10/21 23:52:18 allender
21 * #ifdef'ed out stack debug stuff
23 * Revision 1.6 1995/10/10 12:07:42 allender
26 * Revision 1.5 1995/10/10 11:47:27 allender
27 * put in stack space check
29 * Revision 1.4 1995/08/23 21:34:08 allender
30 * fix mcc compiler warning
32 * Revision 1.3 1995/08/14 14:35:18 allender
33 * changed transparency to 0
35 * Revision 1.2 1995/07/05 16:50:51 allender
36 * transparency/kitchen change
38 * Revision 1.1 1995/05/16 15:24:59 allender
41 * Revision 2.3 1995/03/24 14:49:04 john
42 * Added cheat for player to go thru walls.
44 * Revision 2.2 1995/03/21 17:58:32 john
45 * Fixed bug with normals..
48 * Revision 2.1 1995/03/20 18:15:37 john
49 * Added code to not store the normals in the segment structure.
51 * Revision 2.0 1995/02/27 11:27:41 john
52 * New version 2.0, which has no anonymous unions, builds with
53 * Watcom 10.0, and doesn't require parsing BITMAPS.TBL.
55 * Revision 1.49 1995/02/22 14:45:47 allender
56 * remove anonymous unions from object structure
58 * Revision 1.48 1995/02/22 13:24:50 john
59 * Removed the vecmat anonymous unions.
61 * Revision 1.47 1995/02/07 16:17:26 matt
62 * Disabled all robot-robot collisions except those involving two green
63 * guys. Used to do collisions if either robot was green guy.
65 * Revision 1.46 1995/02/02 14:07:53 matt
66 * Fixed confusion about which segment you are touching when you're
67 * touching a wall. This manifested itself in spurious lava burns.
69 * Revision 1.45 1995/02/02 13:45:53 matt
70 * Made a bunch of lint-inspired changes
72 * Revision 1.44 1995/01/24 12:10:17 matt
73 * Fudged collisions for player/player, and player weapon/other player in
76 * Revision 1.43 1995/01/14 19:16:45 john
77 * First version of new bitmap paging code.
79 * Revision 1.42 1994/12/15 12:22:40 matt
80 * Small change which may or may not help
82 * Revision 1.41 1994/12/14 11:45:51 matt
83 * Fixed (hopefully) little bug with invalid segnum
85 * Revision 1.40 1994/12/13 17:12:01 matt
86 * Increased edge tolerance a bunch more
88 * Revision 1.39 1994/12/13 14:37:59 matt
89 * Fixed another stupid little bug
91 * Revision 1.38 1994/12/13 13:25:44 matt
92 * Increased tolerance massively to avoid catching on corners
94 * Revision 1.37 1994/12/13 12:02:20 matt
97 * Revision 1.36 1994/12/13 11:17:35 matt
98 * Lots of changes to hopefully fix objects leaving the mine. Note that
99 * this code should be considered somewhat experimental - one problem I
100 * know about is that you can get stuck on edges more easily than before.
101 * There may be other problems I don't know about yet.
103 * Revision 1.35 1994/12/12 01:20:57 matt
104 * Added hack in object-object collisions that treats claw guys as
105 * if they have 3/4 of their actual radius.
107 * Revision 1.34 1994/12/04 22:48:39 matt
108 * Physics & FVI now only build seglist for player objects, and they
109 * responsilby deal with buffer full conditions
111 * Revision 1.33 1994/12/04 22:07:05 matt
112 * Added better handing of buffer full condition
114 * Revision 1.32 1994/12/01 21:06:33 matt
115 * Several important changes:
116 * (1) Checking against triangulated sides has been standardized a bit
117 * (2) Code has been added to de-triangulate some sides
118 * (3) BIG ONE: the tolerance for checking a point against a plane has
119 * been drastically relaxed
122 * Revision 1.31 1994/11/27 23:15:03 matt
123 * Made changes for new mprintf calling convention
125 * Revision 1.30 1994/11/19 15:20:30 mike
126 * rip out unused code and data
128 * Revision 1.29 1994/11/16 12:18:17 mike
129 * hack for green_guy:green_guy collision detection.
131 * Revision 1.28 1994/11/10 13:08:54 matt
132 * Added support for new run-length-encoded bitmaps
134 * Revision 1.27 1994/10/31 12:27:51 matt
135 * Added new function object_intersects_wall()
137 * Revision 1.26 1994/10/20 13:59:27 matt
140 * Revision 1.25 1994/10/09 23:51:09 matt
141 * Made find_hitpoint_uv() work with triangulated sides
143 * Revision 1.24 1994/09/25 00:39:29 matt
146 * Revision 1.23 1994/09/25 00:37:53 matt
147 * Made the 'find the point in the bitmap where something hit' system
148 * publicly accessible.
150 * Revision 1.22 1994/09/21 16:58:22 matt
151 * Fixed bug in trans wall check that was checking against verically
152 * flipped bitmap (i.e., the y coord was negative when checking).
154 * Revision 1.21 1994/09/02 11:31:40 matt
155 * Fixed object/object collisions, so you can't fly through robots anymore.
156 * Cleaned up object damage system.
158 * Revision 1.20 1994/08/26 09:42:03 matt
159 * Increased the size of a buffer
161 * Revision 1.19 1994/08/11 18:57:53 mike
162 * Convert shorts to ints for optimization.
164 * Revision 1.18 1994/08/08 21:38:24 matt
165 * Put in small optimization
167 * Revision 1.17 1994/08/08 12:21:52 yuan
170 * Revision 1.16 1994/08/08 11:47:04 matt
171 * Cleaned up fvi and physics a little
173 * Revision 1.15 1994/08/04 00:21:04 matt
174 * Cleaned up fvi & physics error handling; put in code to make sure objects
175 * are in correct segment; simplified segment finding for objects and points
177 * Revision 1.14 1994/08/02 19:04:26 matt
178 * Cleaned up vertex list functions
180 * Revision 1.13 1994/08/02 09:56:28 matt
181 * Put in check for bad value find_plane_line_intersection()
183 * Revision 1.12 1994/08/01 17:27:26 matt
184 * Added support for triangulated walls in trans point check
186 * Revision 1.11 1994/08/01 13:30:40 matt
187 * Made fvi() check holes in transparent walls, and changed fvi() calling
188 * parms to take all input data in query structure.
190 * Revision 1.10 1994/07/13 21:47:17 matt
191 * FVI() and physics now keep lists of segments passed through which the
194 * Revision 1.9 1994/07/09 21:21:40 matt
195 * Fixed, hopefull, bugs in sphere-to-vector intersection code
197 * Revision 1.8 1994/07/08 14:26:42 matt
198 * Non-needed powerups don't get picked up now; this required changing FVI to
199 * take a list of ingore objects rather than just one ignore object.
201 * Revision 1.7 1994/07/06 20:02:37 matt
202 * Made change to match gameseg that uses lowest point number as reference
203 * point when checking against a plane
205 * Revision 1.6 1994/06/29 15:43:58 matt
206 * When computing intersection of vector and sphere, use the radii of both
209 * Revision 1.5 1994/06/14 15:57:58 matt
210 * Took out asserts, and added other hacks, pending real bug fixes
212 * Revision 1.4 1994/06/13 23:10:08 matt
213 * Fixed problems with triangulated sides
215 * Revision 1.3 1994/06/09 12:11:14 matt
216 * Fixed confusing use of two variables, hit_objnum & fvi_hit_object, to
217 * keep the same information in different ways.
219 * Revision 1.2 1994/06/09 09:58:38 matt
220 * Moved find_vector_intersection() from physics.c to new file fvi.c
222 * Revision 1.1 1994/06/09 09:25:57 matt
229 #define NEW_FVI_STUFF 1
259 extern int Physics_cheat_flag;
261 #define face_type_num(nfaces,face_num,tri_edge) ((nfaces==1)?0:(tri_edge*2 + face_num))
265 //find the point on the specified plane where the line intersects
266 //returns true if point found, false if line parallel to plane
267 //new_pnt is the found point on the plane
268 //plane_pnt & plane_norm describe the plane
269 //p0 & p1 are the ends of the line
270 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)
275 vm_vec_sub(&d,p1,p0);
276 vm_vec_sub(&w,p0,plane_pnt);
278 num = vm_vec_dot(plane_norm,&w);
279 den = -vm_vec_dot(plane_norm,&d);
281 //Why does this assert hit so often
282 // Assert(num > -rad);
284 num -= rad; //move point out by rad
286 //check for various bad values
288 if ( (den==0) || //moving parallel to wall, so can't hit it
290 ( (num>den) || //frac greater than one
291 (-num>>15)>=den)) || //will overflow (large negative)
292 (den<0 && num<den)) //frac greater than one
295 //if (num>0) {mprintf(1,"HEY! num>0 in FVI!!!"); return 0;}
297 // Assert(num >= den);
299 //do check for potenial overflow
303 if (labs(num)/(f1_0/2) >= labs(den)) {Int3(); return 0;}
306 Assert(k<=f1_0); //should be trapped above
309 if (oflow_check(d.x,k) || oflow_check(d.y,k) || oflow_check(d.z,k)) return 0;
310 //Note: it is ok for k to be greater than 1, since this might mean
311 //that an object with a non-zero radius that moved from p0 to p1
312 //actually hit the wall on the "other side" of p0.
315 vm_vec_scale2(&d,num,den);
317 vm_vec_add(new_pnt,p0,&d);
319 //we should have vm_vec_scale2_add2()
325 typedef struct vec2d {
329 //given largest componant of normal, return i & j
330 //if largest componant is negative, swap i & j
331 int ij_table[3][2] = {
332 {2,1}, //pos x biggest
333 {0,2}, //pos y biggest
334 {1,0}, //pos z biggest
338 #define IT_NONE 0 //doesn't touch face at all
339 #define IT_FACE 1 //touches face
340 #define IT_EDGE 2 //touches edge of face
341 #define IT_POINT 3 //touches vertex
343 //see if a point in inside a face by projecting into 2d
344 uint check_point_to_face(vms_vector *checkp, side *s,int facenum,int nv,int *vertex_list)
346 vms_vector_array *checkp_array;
347 vms_vector_array norm;
354 vms_vector_array *v0,*v1;
357 get_side_normal(sp, s-sp->sides, facenum, (vms_vector *)&norm );
359 memcpy( &norm, &s->normals[facenum], sizeof(vms_vector_array));
361 checkp_array = (vms_vector_array *)checkp;
363 //now do 2d check to see if point is in side
365 //project polygon onto plane by finding largest component of normal
366 t.x = labs(norm.xyz[0]); t.y = labs(norm.xyz[1]); t.z = labs(norm.xyz[2]);
368 if (t.x > t.y) if (t.x > t.z) biggest=0; else biggest=2;
369 else if (t.y > t.z) biggest=1; else biggest=2;
371 if (norm.xyz[biggest] > 0) {
372 i = ij_table[biggest][0];
373 j = ij_table[biggest][1];
376 i = ij_table[biggest][1];
377 j = ij_table[biggest][0];
380 //now do the 2d problem in the i,j plane
382 check_i = checkp_array->xyz[i];
383 check_j = checkp_array->xyz[j];
385 for (edge=edgemask=0;edge<nv;edge++) {
386 vec2d edgevec,checkvec;
389 v0 = (vms_vector_array *)&Vertices[vertex_list[facenum*3+edge]];
390 v1 = (vms_vector_array *)&Vertices[vertex_list[facenum*3+((edge+1)%nv)]];
392 edgevec.i = v1->xyz[i] - v0->xyz[i];
393 edgevec.j = v1->xyz[j] - v0->xyz[j];
395 checkvec.i = check_i - v0->xyz[i];
396 checkvec.j = check_j - v0->xyz[j];
398 d = fixmul(checkvec.i,edgevec.j) - fixmul(checkvec.j,edgevec.i);
400 if (d < 0) //we are outside of triangle
401 edgemask |= (1<<edge);
409 //check if a sphere intersects a face
410 int check_sphere_to_face(vms_vector *pnt, side *s,int facenum,int nv,fix rad,int *vertex_list)
412 vms_vector checkp=*pnt;
415 //now do 2d check to see if point is in side
417 edgemask = check_point_to_face(pnt,s,facenum,nv,vertex_list);
419 //we've gone through all the sides, are we inside?
424 vms_vector edgevec,checkvec; //this time, real 3d vectors
425 vms_vector closest_point;
431 //get verts for edge we're behind
433 for (edgenum=0;!(edgemask&1);(edgemask>>=1),edgenum++);
435 v0 = &Vertices[vertex_list[facenum*3+edgenum]];
436 v1 = &Vertices[vertex_list[facenum*3+((edgenum+1)%nv)]];
438 //check if we are touching an edge or point
440 vm_vec_sub(&checkvec,&checkp,v0);
441 edgelen = vm_vec_normalized_dir(&edgevec,v1,v0);
443 //find point dist from planes of ends of edge
445 d = vm_vec_dot(&edgevec,&checkvec);
447 if (d+rad < 0) return IT_NONE; //too far behind start point
449 if (d-rad > edgelen) return IT_NONE; //too far part end point
451 //find closest point on edge to check point
455 if (d < 0) closest_point = *v0;
456 else if (d > edgelen) closest_point = *v1;
460 //vm_vec_scale(&edgevec,d);
461 //vm_vec_add(&closest_point,v0,&edgevec);
463 vm_vec_scale_add(&closest_point,v0,&edgevec,d);
466 dist = vm_vec_dist(&checkp,&closest_point);
469 return (itype==IT_POINT)?IT_NONE:itype;
477 //returns true if line intersects with face. fills in newp with intersection
478 //point on plane, whether or not line intersects side
479 //facenum determines which of four possible faces we have
480 //note: the seg parm is temporary, until the face itself has a point field
481 int check_line_to_face(vms_vector *newp,vms_vector *p0,vms_vector *p1,segment *seg,int side,int facenum,int nv,fix rad)
485 struct side *s=&seg->sides[side];
492 get_side_normal(seg, side, facenum, &norm );
494 norm = seg->sides[side].normals[facenum];
497 if ((seg-Segments)==-1)
498 Error("segnum == -1 in check_line_to_face()");
500 create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
502 //use lowest point number
504 vertnum = min(vertex_list[0],vertex_list[2]);
508 vertnum = vertex_list[0];
510 if (vertex_list[i] < vertnum)
511 vertnum = vertex_list[i];
514 pli = find_plane_line_intersection(newp,&Vertices[vertnum],&norm,p0,p1,rad);
516 if (!pli) return IT_NONE;
520 //if rad != 0, project the point down onto the plane of the polygon
523 vm_vec_scale_add2(&checkp,&norm,-rad);
525 return check_sphere_to_face(&checkp,s,facenum,nv,rad,vertex_list);
529 //returns the value of a determinant
530 fix calc_det_value(vms_matrix *det)
532 return fixmul(det->rvec.x,fixmul(det->uvec.y,det->fvec.z)) -
533 fixmul(det->rvec.x,fixmul(det->uvec.z,det->fvec.y)) -
534 fixmul(det->rvec.y,fixmul(det->uvec.x,det->fvec.z)) +
535 fixmul(det->rvec.y,fixmul(det->uvec.z,det->fvec.x)) +
536 fixmul(det->rvec.z,fixmul(det->uvec.x,det->fvec.y)) -
537 fixmul(det->rvec.z,fixmul(det->uvec.y,det->fvec.x));
540 //computes the parameters of closest approach of two lines
541 //fill in two parameters, t0 & t1. returns 0 if lines are parallel, else 1
542 int check_line_to_line(fix *t1,fix *t2,vms_vector *p1,vms_vector *v1,vms_vector *p2,vms_vector *v2)
545 fix d,cross_mag2; //mag squared cross product
547 vm_vec_sub(&det.rvec,p2,p1);
548 vm_vec_cross(&det.fvec,v1,v2);
549 cross_mag2 = vm_vec_dot(&det.fvec,&det.fvec);
552 return 0; //lines are parallel
555 d = calc_det_value(&det);
556 if (oflow_check(d,cross_mag2))
559 *t1 = fixdiv(d,cross_mag2);
562 d = calc_det_value(&det);
563 if (oflow_check(d,cross_mag2))
566 *t2 = fixdiv(d,cross_mag2);
568 return 1; //found point
572 int disable_new_fvi_stuff=0;
574 #define disable_new_fvi_stuff 1
577 //this version is for when the start and end positions both poke through
578 //the plane of a side. In this case, we must do checks against the edge
580 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)
583 fix edge_t,move_t,edge_t2,move_t2,closest_dist;
584 fix edge_len,move_len;
586 int num_faces,edgenum;
588 vms_vector *edge_v0,*edge_v1,edge_vec;
589 struct side *s=&seg->sides[side];
590 vms_vector closest_point_edge,closest_point_move;
592 if (disable_new_fvi_stuff)
593 return check_line_to_face(newp,p0,p1,seg,side,facenum,nv,rad);
595 //calc some basic stuff
597 if ((seg-Segments)==-1)
598 Error("segnum == -1 in special_check_line_to_face()");
600 create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
601 vm_vec_sub(&move_vec,p1,p0);
603 //figure out which edge(s) to check against
605 edgemask = check_point_to_face(p0,s,facenum,nv,vertex_list);
608 return check_line_to_face(newp,p0,p1,seg,side,facenum,nv,rad);
610 for (edgenum=0;!(edgemask&1);edgemask>>=1,edgenum++);
612 edge_v0 = &Vertices[vertex_list[facenum*3+edgenum]];
613 edge_v1 = &Vertices[vertex_list[facenum*3+((edgenum+1)%nv)]];
615 vm_vec_sub(&edge_vec,edge_v1,edge_v0);
617 //is the start point already touching the edge?
621 //first, find point of closest approach of vec & edge
623 edge_len = vm_vec_normalize(&edge_vec);
624 move_len = vm_vec_normalize(&move_vec);
626 check_line_to_line(&edge_t,&move_t,edge_v0,&edge_vec,p0,&move_vec);
628 //make sure t values are in valid range
630 if (move_t<0 || move_t>move_len+rad)
633 if (move_t > move_len)
638 if (edge_t < 0) //saturate at points
643 if (edge_t2 > edge_len) //saturate at points
646 //now, edge_t & move_t determine closest points. calculate the points.
648 vm_vec_scale_add(&closest_point_edge,edge_v0,&edge_vec,edge_t2);
649 vm_vec_scale_add(&closest_point_move,p0,&move_vec,move_t2);
651 //find dist between closest points
653 closest_dist = vm_vec_dist(&closest_point_edge,&closest_point_move);
655 //could we hit with this dist?
657 //note massive tolerance here
658 // if (closest_dist < (rad*18)/20) { //we hit. figure out where
659 if (closest_dist < (rad*15)/20) { //we hit. figure out where
661 //now figure out where we hit
663 vm_vec_scale_add(newp,p0,&move_vec,move_t-rad);
669 return IT_NONE; //no hit
673 //maybe this routine should just return the distance and let the caller
674 //decide it it's close enough to hit
675 //determine if and where a vector intersects with a sphere
676 //vector defined by p0,p1
677 //returns dist if intersects, and fills in intp
679 int check_vector_to_sphere_1(vms_vector *intp,vms_vector *p0,vms_vector *p1,vms_vector *sphere_pos,fix sphere_rad)
681 vms_vector d,dn,w,closest_point;
682 fix mag_d,dist,w_dist,int_dist;
684 //this routine could be optimized if it's taking too much time!
686 vm_vec_sub(&d,p1,p0);
687 vm_vec_sub(&w,sphere_pos,p0);
689 mag_d = vm_vec_copy_normalize(&dn,&d);
692 int_dist = vm_vec_mag(&w);
694 return (int_dist<sphere_rad)?int_dist:0;
697 w_dist = vm_vec_dot(&dn,&w);
699 if (w_dist < 0) //moving away from object
702 if (w_dist > mag_d+sphere_rad)
703 return 0; //cannot hit
705 vm_vec_scale_add(&closest_point,p0,&dn,w_dist);
707 dist = vm_vec_dist(&closest_point,sphere_pos);
709 if (dist < sphere_rad) {
710 fix dist2,rad2,shorten;
712 dist2 = fixmul(dist,dist);
713 rad2 = fixmul(sphere_rad,sphere_rad);
715 shorten = fix_sqrt(rad2 - dist2);
717 int_dist = w_dist-shorten;
719 if (int_dist > mag_d || int_dist < 0) {
720 //past one or the other end of vector, which means we're inside
722 *intp = *p0; //don't move at all
726 vm_vec_scale_add(intp,p0,&dn,int_dist); //calc intersection point
729 // fix dd = vm_vec_dist(intp,sphere_pos);
730 // Assert(dd == sphere_rad);
731 // mprintf(0,"dd=%x, rad=%x, delta=%x\n",dd,sphere_rad,dd-sphere_rad);
742 //$$fix get_sphere_int_dist(vms_vector *w,fix dist,fix rad);
744 //$$#pragma aux get_sphere_int_dist parm [esi] [ebx] [ecx] value [eax] modify exact [eax ebx ecx edx] = \
757 //$$ "call quad_sqrt" \
764 //$$ "mov eax,[esi]" \
768 //$$ "mov eax,4[esi]" \
772 //$$ "mov eax,8[esi]" \
783 //$$ "call quad_sqrt" \
789 //$$//determine if and where a vector intersects with a sphere
790 //$$//vector defined by p0,p1
791 //$$//returns dist if intersects, and fills in intp. if no intersect, return 0
792 //$$fix check_vector_to_sphere_2(vms_vector *intp,vms_vector *p0,vms_vector *p1,vms_vector *sphere_pos,fix sphere_rad)
794 //$$ vms_vector d,w,c;
795 //$$ fix mag_d,dist,mag_c,mag_w;
796 //$$ vms_vector wn,dn;
798 //$$ vm_vec_sub(&d,p1,p0);
799 //$$ vm_vec_sub(&w,sphere_pos,p0);
801 //$$ //wn = w; mag_w = vm_vec_normalize(&wn);
802 //$$ //dn = d; mag_d = vm_vec_normalize(&dn);
804 //$$ mag_w = vm_vec_copy_normalize(&wn,&w);
805 //$$ mag_d = vm_vec_copy_normalize(&dn,&d);
807 //$$ //vm_vec_cross(&c,&w,&d);
808 //$$ vm_vec_cross(&c,&wn,&dn);
810 //$$ mag_c = vm_vec_mag(&c);
811 //$$ //mag_d = vm_vec_mag(&d);
813 //$$ //dist = fixdiv(mag_c,mag_d);
815 //$$dist = fixmul(mag_c,mag_w);
817 //$$ if (dist < sphere_rad) { //we intersect. find point of intersection
818 //$$ fix int_dist; //length of vector to intersection point
819 //$$ fix k; //portion of p0p1 we want
820 //$$//@@ fix dist2,rad2,shorten,mag_w2;
822 //$$//@@ mag_w2 = vm_vec_dot(&w,&w); //the square of the magnitude
823 //$$//@@ //WHAT ABOUT OVERFLOW???
824 //$$//@@ dist2 = fixmul(dist,dist);
825 //$$//@@ rad2 = fixmul(sphere_rad,sphere_rad);
826 //$$//@@ shorten = fix_sqrt(rad2 - dist2);
827 //$$//@@ int_dist = fix_sqrt(mag_w2 - dist2) - shorten;
829 //$$ int_dist = get_sphere_int_dist(&w,dist,sphere_rad);
831 //$$if (labs(int_dist) > mag_d) //I don't know why this would happen
832 //$$ if (int_dist > 0)
837 //$$ k = fixdiv(int_dist,mag_d);
839 //$$// vm_vec_scale(&d,k); //vec from p0 to intersection point
840 //$$// vm_vec_add(intp,p0,&d); //intersection point
841 //$$ vm_vec_scale_add(intp,p0,&d,k); //calc new intersection point
843 //$$ return int_dist;
846 //$$ return 0; //no intersection
850 //determine if a vector intersects with an object
851 //if no intersects, returns 0, else fills in intp and returns dist
852 fix check_vector_to_object(vms_vector *intp,vms_vector *p0,vms_vector *p1,fix rad,object *obj,object *otherobj)
854 fix size = obj->size;
856 if (obj->type == OBJ_ROBOT && Robot_info[obj->id].attack_type)
859 //if obj is player, and bumping into other player or a weapon of another coop player, reduce radius
860 if (obj->type == OBJ_PLAYER &&
861 ((otherobj->type == OBJ_PLAYER) ||
862 ((Game_mode&GM_MULTI_COOP) && otherobj->type == OBJ_WEAPON && otherobj->ctype.laser_info.parent_type == OBJ_PLAYER)))
865 return check_vector_to_sphere_1(intp,p0,p1,&obj->pos,size+rad);
870 #define MAX_SEGS_VISITED 100
872 short segs_visited[MAX_SEGS_VISITED];
876 //these vars are used to pass vars from fvi_sub() to find_vector_intersection()
877 int fvi_hit_object; // object number of object hit in last find_vector_intersection call.
878 int fvi_hit_seg; // what segment the hit point is in
879 int fvi_hit_side; // what side was hit
880 int fvi_hit_side_seg;// what seg the hitside is in
881 vms_vector wall_norm; //ptr to surface normal of hit wall
882 int fvi_hit_seg2; // what segment the hit point is in
884 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);
886 //What the hell is fvi_hit_seg for???
888 //Find out if a vector intersects with anything.
889 //Fills in hit_data, an fvi_info structure (see header file).
891 // p0 & startseg describe the start of the vector
892 // p1 the end of the vector
893 // rad the radius of the cylinder
894 // thisobjnum used to prevent an object with colliding with itself
895 // ingore_obj ignore collisions with this object
896 // check_obj_flag determines whether collisions with objects are checked
897 //Returns the hit_data->hit_type
898 int find_vector_intersection(fvi_query *fq,fvi_info *hit_data)
900 int hit_type,hit_seg,hit_seg2;
904 Assert(fq->ignore_obj_list != (int *)(-1));
905 Assert((fq->startseg <= Highest_segment_index) && (fq->startseg >= 0));
912 //check to make sure start point is in seg its supposed to be in
913 //Assert(check_point_in_seg(p0,startseg,0).centermask==0); //start point not in seg
915 // Viewer is not in segment as claimed, so say there is no hit.
916 if(!(get_seg_masks(fq->p0,fq->startseg,0).centermask==0)) {
918 hit_data->hit_type = HIT_BAD_P0;
919 hit_data->hit_pnt = *fq->p0;
920 hit_data->hit_seg = fq->startseg;
921 hit_data->hit_side = hit_data->hit_object = 0;
922 hit_data->hit_side_seg = -1;
924 return hit_data->hit_type;
927 segs_visited[0] = fq->startseg;
933 hit_seg2 = fvi_hit_seg2 = -1;
935 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);
936 //!!hit_seg = find_point_seg(&hit_pnt,fq->startseg);
937 if (hit_seg2!=-1 && !get_seg_masks(&hit_pnt,hit_seg2,0).centermask)
940 hit_seg = find_point_seg(&hit_pnt,fq->startseg);
942 //MATT: TAKE OUT THIS HACK AND FIX THE BUGS!
943 if (hit_type == HIT_WALL && hit_seg==-1)
944 if (fvi_hit_seg2!=-1 && get_seg_masks(&hit_pnt,fvi_hit_seg2,0).centermask==0)
945 hit_seg = fvi_hit_seg2;
950 vms_vector new_hit_pnt;
952 //because of code that deal with object with non-zero radius has
953 //problems, try using zero radius and see if we hit a wall
955 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);
957 if (new_hit_seg2 != -1) {
958 hit_seg = new_hit_seg2;
959 hit_pnt = new_hit_pnt;
964 if (hit_seg!=-1 && fq->flags&FQ_GET_SEGLIST)
965 if (hit_seg != hit_data->seglist[hit_data->n_segs-1] && hit_data->n_segs<MAX_FVI_SEGS-1)
966 hit_data->seglist[hit_data->n_segs++] = hit_seg;
968 if (hit_seg!=-1 && fq->flags&FQ_GET_SEGLIST)
969 for (i=0;i<hit_data->n_segs && i<MAX_FVI_SEGS-1;i++)
970 if (hit_data->seglist[i] == hit_seg) {
971 hit_data->n_segs = i+1;
975 //I'm sorry to say that sometimes the seglist isn't correct. I did my
979 //{ //verify hit list
983 // Assert(hit_data->seglist[0] == startseg);
985 // for (i=0;i<hit_data->n_segs-1;i++) {
986 // for (ch=0;ch<6;ch++)
987 // if (Segments[hit_data->seglist[i]].children[ch] == hit_data->seglist[i+1])
992 // Assert(hit_data->seglist[hit_data->n_segs-1] == hit_seg);
996 //MATT: PUT THESE ASSERTS BACK IN AND FIX THE BUGS!
997 //!! Assert(hit_seg!=-1);
998 //!! Assert(!((hit_type==HIT_WALL) && (hit_seg == -1)));
999 //When this assert happens, get Matt. Matt: Look at hit_seg2 &
1000 //fvi_hit_seg. At least one of these should be set. Why didn't
1001 //find_new_seg() find something?
1003 // Assert(fvi_hit_seg==-1 || fvi_hit_seg == hit_seg);
1005 Assert(!(hit_type==HIT_OBJECT && fvi_hit_object==-1));
1007 hit_data->hit_type = hit_type;
1008 hit_data->hit_pnt = hit_pnt;
1009 hit_data->hit_seg = hit_seg;
1010 hit_data->hit_side = fvi_hit_side; //looks at global
1011 hit_data->hit_side_seg = fvi_hit_side_seg; //looks at global
1012 hit_data->hit_object = fvi_hit_object; //looks at global
1013 hit_data->hit_wallnorm = wall_norm; //looks at global
1015 // if(hit_seg!=-1 && get_seg_masks(&hit_data->hit_pnt,hit_data->hit_seg,0).centermask!=0)
1022 //--unused-- fix check_dist(vms_vector *v0,vms_vector *v1)
1024 //--unused-- return vm_vec_dist(v0,v1);
1027 int obj_in_list(int objnum,int *obj_list)
1031 while ((t=*obj_list)!=-1 && t!=objnum) obj_list++;
1037 int check_trans_wall(vms_vector *pnt,segment *seg,int sidenum,int facenum);
1039 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)
1041 segment *seg; //the segment we're looking at
1042 int startmask,endmask; //mask of faces
1043 //@@int sidemask; //mask of sides - can be on back of face but not side
1044 int centermask; //where the center point is
1047 vms_vector hit_point,closest_hit_point; //where we hit
1048 fix d,closest_d=0x7fffffff; //distance to hit point
1049 int hit_type=HIT_NONE; //what sort of hit
1051 int hit_none_seg=-1;
1052 int hit_none_n_segs=0;
1053 int hit_none_seglist[MAX_FVI_SEGS];
1054 int cur_nest_level = fvi_nest_count;
1056 //fvi_hit_object = -1;
1058 if (flags&FQ_GET_SEGLIST)
1059 *seglist = startseg;
1062 seg = &Segments[startseg];
1066 //first, see if vector hit any objects in this segment
1067 if (flags & FQ_CHECK_OBJS)
1068 for (objnum=seg->objects;objnum!=-1;objnum=Objects[objnum].next)
1069 if ( !(Objects[objnum].flags & OF_SHOULD_BE_DEAD) &&
1070 !(thisobjnum == objnum ) &&
1071 (ignore_obj_list==NULL || !obj_in_list(objnum,ignore_obj_list)) &&
1072 !laser_are_related( objnum, thisobjnum ) &&
1073 !((thisobjnum > -1) &&
1074 (CollisionResult[Objects[thisobjnum].type][Objects[objnum].type] == RESULT_NOTHING ) &&
1075 (CollisionResult[Objects[objnum].type][Objects[thisobjnum].type] == RESULT_NOTHING ))) {
1076 int fudged_rad = rad;
1078 // If this is a powerup, don't do collision if flag FQ_IGNORE_POWERUPS is set
1079 if (Objects[objnum].type == OBJ_POWERUP)
1080 if (flags & FQ_IGNORE_POWERUPS)
1083 // If this is a robot:robot collision, only do it if both of them have attack_type != 0 (eg, green guy)
1084 if (Objects[thisobjnum].type == OBJ_ROBOT)
1085 if (Objects[objnum].type == OBJ_ROBOT)
1086 // -- 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))
1089 if (Objects[thisobjnum].type == OBJ_ROBOT && Robot_info[Objects[thisobjnum].id].attack_type)
1090 fudged_rad = (rad*3)/4;
1092 //if obj is player, and bumping into other player or a weapon of another coop player, reduce radius
1093 if (Objects[thisobjnum].type == OBJ_PLAYER &&
1094 ((Objects[objnum].type == OBJ_PLAYER) ||
1095 ((Game_mode&GM_MULTI_COOP) && Objects[objnum].type == OBJ_WEAPON && Objects[objnum].ctype.laser_info.parent_type == OBJ_PLAYER)))
1096 fudged_rad = rad/2; //(rad*3)/4;
1098 d = check_vector_to_object(&hit_point,p0,p1,fudged_rad,&Objects[objnum],&Objects[thisobjnum]);
1100 if (d) //we have intersection
1101 if (d < closest_d) {
1102 fvi_hit_object = objnum;
1103 Assert(fvi_hit_object!=-1);
1105 closest_hit_point = hit_point;
1106 hit_type=HIT_OBJECT;
1110 if ( (thisobjnum > -1 ) && (CollisionResult[Objects[thisobjnum].type][OBJ_WALL] == RESULT_NOTHING ) )
1111 rad = 0; //HACK - ignore when edges hit walls
1113 //now, check segment walls
1115 startmask = get_seg_masks(p0,startseg,rad).facemask;
1117 masks = get_seg_masks(p1,startseg,rad); //on back of which faces?
1118 endmask = masks.facemask;
1119 //@@sidemask = masks.sidemask;
1120 centermask = masks.centermask;
1122 if (centermask==0) hit_none_seg = startseg;
1124 if (endmask != 0) { //on the back of at least one face
1128 //for each face we are on the back of, check if intersected
1130 for (side=0,bit=1;side<6 && endmask>=bit;side++) {
1132 num_faces = get_num_faces(&seg->sides[side]);
1137 // commented out by mk on 02/13/94:: if ((num_faces=seg->sides[side].num_faces)==0) num_faces=1;
1139 for (face=0;face<2;face++,bit<<=1) {
1141 if (endmask & bit) { //on the back of this face
1142 int face_hit_type; //in what way did we hit the face?
1145 if (seg->children[side] == entry_seg)
1146 continue; //don't go back through entry side
1148 //did we go through this wall/door?
1150 //#ifdef NEW_FVI_STUFF
1151 if (startmask & bit) //start was also though. Do extra check
1152 face_hit_type = special_check_line_to_face( &hit_point,
1155 ((num_faces==1)?4:3),rad);
1158 //NOTE LINK TO ABOVE!!
1159 face_hit_type = check_line_to_face( &hit_point,
1162 ((num_faces==1)?4:3),rad);
1165 if (face_hit_type) { //through this wall/door
1168 //if what we have hit is a door, check the adjoining seg
1170 if ( (thisobjnum == Players[Player_num].objnum) && (Physics_cheat_flag==0xBADA55) ) {
1171 wid_flag = WALL_IS_DOORWAY(seg, side);
1172 if (seg->children[side] >= 0 )
1173 wid_flag |= WID_FLY_FLAG;
1175 wid_flag = WALL_IS_DOORWAY(seg, side);
1178 if ((wid_flag & WID_FLY_FLAG) ||
1179 (((wid_flag & WID_RENDER_FLAG) && (wid_flag & WID_RENDPAST_FLAG)) &&
1180 ((flags & FQ_TRANSWALL) || (flags & FQ_TRANSPOINT && check_trans_wall(&hit_point,seg,side,face))))) {
1183 vms_vector sub_hit_point;
1184 int sub_hit_type,sub_hit_seg;
1185 vms_vector save_wall_norm = wall_norm;
1186 int save_hit_objnum=fvi_hit_object;
1189 //do the check recursively on the next seg.
1191 newsegnum = seg->children[side];
1193 for (i=0;i<n_segs_visited && newsegnum!=segs_visited[i];i++);
1195 if (i==n_segs_visited) { //haven't visited here yet
1196 int temp_seglist[MAX_FVI_SEGS],temp_n_segs;
1198 segs_visited[n_segs_visited++] = newsegnum;
1200 if (n_segs_visited >= MAX_SEGS_VISITED)
1201 goto quit_looking; //we've looked a long time, so give up
1203 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);
1205 if (sub_hit_type != HIT_NONE) {
1207 d = vm_vec_dist(&sub_hit_point,p0);
1209 if (d < closest_d) {
1212 closest_hit_point = sub_hit_point;
1213 hit_type = sub_hit_type;
1214 if (sub_hit_seg!=-1) hit_seg = sub_hit_seg;
1217 if (flags&FQ_GET_SEGLIST) {
1219 for (ii=0;i<temp_n_segs && *n_segs<MAX_FVI_SEGS-1;)
1220 seglist[(*n_segs)++] = temp_seglist[ii++];
1223 Assert(*n_segs < MAX_FVI_SEGS);
1226 wall_norm = save_wall_norm; //global could be trashed
1227 fvi_hit_object = save_hit_objnum;
1232 wall_norm = save_wall_norm; //global could be trashed
1233 if (sub_hit_seg!=-1) hit_none_seg = sub_hit_seg;
1235 if (flags&FQ_GET_SEGLIST) {
1237 for (ii=0;ii<temp_n_segs && ii<MAX_FVI_SEGS-1;ii++)
1238 hit_none_seglist[ii] = temp_seglist[ii];
1240 hit_none_n_segs = temp_n_segs;
1246 //is this the closest hit?
1248 d = vm_vec_dist(&hit_point,p0);
1250 if (d < closest_d) {
1252 closest_hit_point = hit_point;
1253 hit_type = HIT_WALL;
1256 get_side_normal(seg, side, face, &wall_norm );
1258 wall_norm = seg->sides[side].normals[face];
1262 if (get_seg_masks(&hit_point,startseg,rad).centermask==0)
1263 hit_seg = startseg; //hit in this segment
1265 fvi_hit_seg2 = startseg;
1268 //@@ mprintf( 0, "Warning on line 991 in physics.c\n" );
1269 //@@ hit_seg = startseg; //hit in this segment
1273 fvi_hit_seg = hit_seg;
1274 fvi_hit_side = side;
1275 fvi_hit_side_seg = startseg;
1285 // Assert(centermask==0 || hit_seg!=startseg);
1287 // Assert(sidemask==0); //Error("Didn't find side we went though");
1292 if (hit_type == HIT_NONE) { //didn't hit anything, return end point
1296 *ints = hit_none_seg;
1297 //MATT: MUST FIX THIS!!!!
1298 //Assert(!centermask);
1300 if (hit_none_seg!=-1) { ///(centermask == 0)
1301 if (flags&FQ_GET_SEGLIST)
1303 for (i=0;i<hit_none_n_segs && *n_segs<MAX_FVI_SEGS-1;)
1304 seglist[(*n_segs)++] = hit_none_seglist[i++];
1307 if (cur_nest_level!=0)
1312 *intp = closest_hit_point;
1314 if (fvi_hit_seg2 != -1)
1315 *ints = fvi_hit_seg2;
1317 *ints = hit_none_seg;
1322 Assert(!(hit_type==HIT_OBJECT && fvi_hit_object==-1));
1329 //--unused-- //compute the magnitude of a 2d vector
1330 //--unused-- fix mag2d(vec2d *v);
1331 //--unused-- #pragma aux mag2d parm [esi] value [eax] modify exact [eax ebx ecx edx] = \
1332 //--unused-- "mov eax,[esi]" \
1333 //--unused-- "imul eax" \
1334 //--unused-- "mov ebx,eax" \
1335 //--unused-- "mov ecx,edx" \
1336 //--unused-- "mov eax,4[esi]" \
1337 //--unused-- "imul eax" \
1338 //--unused-- "add eax,ebx" \
1339 //--unused-- "adc edx,ecx" \
1340 //--unused-- "call quad_sqrt";
1343 //--unused-- //returns mag
1344 //--unused-- fix normalize_2d(vec2d *v)
1346 //--unused-- fix mag;
1348 //--unused-- mag = mag2d(v);
1350 //--unused-- v->i = fixdiv(v->i,mag);
1351 //--unused-- v->j = fixdiv(v->j,mag);
1353 //--unused-- return mag;
1356 #include "textures.h"
1357 #include "texmerge.h"
1359 #define cross(v0,v1) (fixmul((v0)->i,(v1)->j) - fixmul((v0)->j,(v1)->i))
1361 //finds the uv coords of the given point on the given seg & side
1362 //fills in u & v. if l is non-NULL fills it in also
1363 void find_hitpoint_uv(fix *u,fix *v,fix *l,vms_vector *pnt,segment *seg,int sidenum,int facenum)
1365 vms_vector_array *pnt_array;
1366 vms_vector_array normal_array;
1367 int segnum = seg-Segments;
1370 side *side = &seg->sides[sidenum];
1371 int vertex_list[6],vertnum_list[6];
1372 vec2d p1,vec0,vec1,checkp; //@@,checkv;
1377 //mprintf(0,"\ncheck_trans_wall vec=%x,%x,%x\n",pnt->x,pnt->y,pnt->z);
1379 //do lasers pass through illusory walls?
1381 //when do I return 0 & 1 for non-transparent walls?
1383 if (segnum < 0 || segnum > Highest_segment_index) {
1384 mprintf((0,"Bad segnum (%d) in find_hitpoint_uv()\n",segnum));
1390 Error("segnum == -1 in find_hitpoint_uv()");
1392 create_abs_vertex_lists(&num_faces,vertex_list,segnum,sidenum);
1393 create_all_vertnum_lists(&num_faces,vertnum_list,segnum,sidenum);
1395 //now the hard work.
1397 //1. find what plane to project this wall onto to make it a 2d case
1400 get_side_normal(seg, sidenum, facenum, (vms_vector *)&normal_array );
1402 memcpy( &normal_array, &side->normals[facenum], sizeof(vms_vector_array) );
1406 if (abs(normal_array.xyz[1]) > abs(normal_array.xyz[biggest])) biggest = 1;
1407 if (abs(normal_array.xyz[2]) > abs(normal_array.xyz[biggest])) biggest = 2;
1409 if (biggest == 0) ii=1; else ii=0;
1410 if (biggest == 2) jj=1; else jj=2;
1412 //2. compute u,v of intersection point
1415 pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+1]];
1416 p1.i = pnt_array->xyz[ii];
1417 p1.j = pnt_array->xyz[jj];
1419 pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+0]];
1420 vec0.i = pnt_array->xyz[ii] - p1.i;
1421 vec0.j = pnt_array->xyz[jj] - p1.j;
1424 pnt_array = (vms_vector_array *)&Vertices[vertex_list[facenum*3+2]];
1425 vec1.i = pnt_array->xyz[ii] - p1.i;
1426 vec1.j = pnt_array->xyz[jj] - p1.j;
1428 //vec from 1 -> checkpoint
1429 pnt_array = (vms_vector_array *)pnt;
1430 checkp.i = pnt_array->xyz[ii];
1431 checkp.j = pnt_array->xyz[jj];
1433 //@@checkv.i = checkp.i - p1.i;
1434 //@@checkv.j = checkp.j - p1.j;
1436 //mprintf(0," vec0 = %x,%x ",vec0.i,vec0.j);
1437 //mprintf(0," vec1 = %x,%x ",vec1.i,vec1.j);
1438 //mprintf(0," checkv = %x,%x\n",checkv.i,checkv.j);
1440 k1 = -fixdiv(cross(&checkp,&vec0) + cross(&vec0,&p1),cross(&vec0,&vec1));
1441 if (abs(vec0.i) > abs(vec0.j))
1442 k0 = fixdiv(fixmul(-k1,vec1.i) + checkp.i - p1.i,vec0.i);
1444 k0 = fixdiv(fixmul(-k1,vec1.j) + checkp.j - p1.j,vec0.j);
1446 //mprintf(0," k0,k1 = %x,%x\n",k0,k1);
1449 uvls[i] = side->uvls[vertnum_list[facenum*3+i]];
1451 *u = uvls[1].u + fixmul( k0,uvls[0].u - uvls[1].u) + fixmul(k1,uvls[2].u - uvls[1].u);
1452 *v = uvls[1].v + fixmul( k0,uvls[0].v - uvls[1].v) + fixmul(k1,uvls[2].v - uvls[1].v);
1455 *l = uvls[1].l + fixmul( k0,uvls[0].l - uvls[1].l) + fixmul(k1,uvls[2].l - uvls[1].l);
1457 //mprintf(0," u,v = %x,%x\n",*u,*v);
1460 //check if a particular point on a wall is a transparent pixel
1461 //returns 1 if can pass though the wall, else 0
1462 int check_trans_wall(vms_vector *pnt,segment *seg,int sidenum,int facenum)
1465 side *side = &seg->sides[sidenum];
1469 // Assert(WALL_IS_DOORWAY(seg,sidenum) == WID_TRANSPARENT_WALL);
1471 find_hitpoint_uv(&u,&v,NULL,pnt,seg,sidenum,facenum); // Don't compute light value.
1473 if (side->tmap_num2 != 0) {
1474 bm = texmerge_get_cached_bitmap( side->tmap_num, side->tmap_num2 );
1476 bm = &GameBitmaps[Textures[side->tmap_num].index];
1477 PIGGY_PAGE_IN( Textures[side->tmap_num] );
1480 if (bm->bm_flags & BM_FLAG_RLE)
1481 bm = rle_expand_texture(bm);
1483 bmx = ((unsigned) f2i(u*bm->bm_w)) % bm->bm_w;
1484 bmy = ((unsigned) f2i(v*bm->bm_h)) % bm->bm_h;
1486 //note: the line above had -v, but that was wrong, so I changed it. if
1487 //something doesn't work, and you want to make it negative again, you
1488 //should figure out what's going on.
1490 //mprintf(0," bmx,y = %d,%d, color=%x\n",bmx,bmy,bm->bm_data[bmy*64+bmx]);
1492 return (bm->bm_data[bmy*bm->bm_w+bmx] == TRANSPARENCY_COLOR);
1495 //new function for Mike
1496 //note: n_segs_visited must be set to zero before this is called
1497 int sphere_intersects_wall(vms_vector *pnt,int segnum,fix rad)
1502 segs_visited[n_segs_visited++] = segnum;
1504 facemask = get_seg_masks(pnt,segnum,rad).facemask;
1506 seg = &Segments[segnum];
1508 if (facemask != 0) { //on the back of at least one face
1512 //for each face we are on the back of, check if intersected
1514 for (side=0,bit=1;side<6 && facemask>=bit;side++) {
1516 for (face=0;face<2;face++,bit<<=1) {
1518 if (facemask & bit) { //on the back of this face
1519 int face_hit_type; //in what way did we hit the face?
1520 int num_faces,vertex_list[6];
1522 //did we go through this wall/door?
1524 if ((seg-Segments)==-1)
1525 Error("segnum == -1 in sphere_intersects_wall()");
1527 create_abs_vertex_lists(&num_faces,vertex_list,seg-Segments,side);
1529 face_hit_type = check_sphere_to_face( pnt,&seg->sides[side],
1530 face,((num_faces==1)?4:3),rad,vertex_list);
1532 if (face_hit_type) { //through this wall/door
1535 //if what we have hit is a door, check the adjoining seg
1537 child = seg->children[side];
1539 for (i=0;i<n_segs_visited && child!=segs_visited[i];i++);
1541 if (i==n_segs_visited) { //haven't visited here yet
1543 if (!IS_CHILD(child))
1547 if (sphere_intersects_wall(pnt,child,rad))
1560 //Returns true if the object is through any walls
1561 int object_intersects_wall(object *objp)
1565 return sphere_intersects_wall(&objp->pos,objp->segnum,objp->size);