1 ;THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
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6 ;SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
7 ;FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
8 ;CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
9 ;AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
10 ;COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
12 ; $Source: /cvs/cvsroot/d2x/maths/vecmata.asm,v $
13 ; $Revision: 1.1.1.1 $
15 ; $Date: 2001-01-19 03:29:58 $
17 ; Source for vector/matrix library
19 ; $Log: not supported by cvs2svn $
20 ; Revision 1.1.1.1 1999/06/14 22:13:33 donut
21 ; Import of d1x 1.37 source.
23 ; Revision 1.54 1995/01/31 00:14:50 matt
24 ; Took out int3 from dotprod overflow, since it saturates now
26 ; Revision 1.53 1994/12/14 18:29:33 matt
27 ; Made dotprod overflow check stay in, and return saturated value
29 ; Revision 1.52 1994/12/14 12:34:13 matt
30 ; Disabled now-unused vector_2_matrix_norm()
32 ; Revision 1.51 1994/12/13 16:55:13 matt
33 ; Ripped out optimization from last version, which was bogus
35 ; Revision 1.50 1994/12/13 14:55:18 matt
36 ; Use quick normalize in a couple of places where it was safe to do so
38 ; Revision 1.49 1994/12/13 14:44:12 matt
39 ; Added vm_vector_2_matrix_norm()
41 ; Revision 1.48 1994/12/13 13:26:49 matt
42 ; Fixed overflow check
44 ; Revision 1.47 1994/12/03 15:39:54 matt
45 ; Gracefully handle some vector_2_matrix problems
47 ; Revision 1.46 1994/11/19 17:15:05 matt
48 ; Assemble out some code not used in DESCENT
50 ; Revision 1.45 1994/11/17 11:41:05 matt
51 ; Put handling in extract_angles_from_matrix to deal with bad matrices
53 ; Revision 1.44 1994/11/16 11:48:10 matt
54 ; Added error checking to vm_extract_angles_matrix()
56 ; Revision 1.43 1994/09/19 22:00:10 matt
57 ; Fixed register trash
59 ; Revision 1.42 1994/09/11 19:23:05 matt
60 ; Added vm_vec_normalized_dir_quick()
62 ; Revision 1.41 1994/08/14 13:28:38 matt
63 ; Put in check for zero-length vector in extract angles
65 ; Revision 1.40 1994/07/19 18:52:53 matt
66 ; Added vm_vec_normalize_quick() and vm_vec_copy_normalize_quick()
68 ; Revision 1.39 1994/06/16 18:24:22 matt
69 ; Added vm_vec_mag_quick()
71 ; Revision 1.38 1994/06/10 23:18:38 matt
72 ; Added new code for vm_vec_ang_2_matrix() which may be better, but may
75 ; Revision 1.37 1994/05/22 18:17:29 mike
76 ; Optimize vm_vec_dist_quick, using jns in place of abs_eax.
78 ; Revision 1.36 1994/05/19 12:07:04 matt
79 ; Fixed globals and macros and added a constant
81 ; Revision 1.35 1994/05/19 09:19:00 matt
82 ; Made vm_vec_normalized_dir() return mag of vector
84 ; Revision 1.34 1994/05/18 22:28:01 matt
85 ; Added function vm_vec_normalized_dir()
86 ; Added C macros IS_ZERO_VEC(), vm_vec_zero(), and vm_set_identity()
87 ; Added C global static vars vmd_zero_vector & vmd_identity_matrix
89 ; Revision 1.33 1994/05/18 21:44:16 matt
91 ; vm_extract_angles_vector()
92 ; vm_extract_angles_vector_normalized()
93 ; vm_vec_copy_normalize()
95 ; Revision 1.32 1994/05/13 12:41:51 matt
96 ; Added new function, vm_vec_dist_quick(), which does an approximation.
98 ; Revision 1.31 1994/05/04 17:41:31 mike
99 ; Comment out debug_brk on null vector.
101 ; Revision 1.30 1994/04/15 21:41:31 matt
102 ; Check for foward vector straigt up in extract angles routine
104 ; Revision 1.29 1994/03/30 15:45:05 matt
105 ; Added two functions, vm_vec_scale_add() & vm_vec_scale_add2()
107 ; Revision 1.28 1994/02/26 19:23:35 matt
108 ; Do an int3 when we get a null vector when computing surface normal
110 ; Revision 1.27 1994/02/10 18:29:45 matt
111 ; Changed 'if DEBUG_ON' to 'ifndef NDEBUG'
113 ; Revision 1.26 1994/02/10 18:28:55 matt
114 ; Fixed bugs in extract angles function
116 ; Revision 1.25 1994/01/31 22:46:07 matt
117 ; Added vm_extract_angles_matrix() function
119 ; Revision 1.24 1994/01/30 19:29:55 matt
120 ; Put in debug_brk when vm_vec_2_matrix got zero-length vector
122 ; Revision 1.23 1994/01/25 15:27:59 matt
123 ; Added debugging check for dotprod overflow
125 ; Revision 1.22 1994/01/24 11:52:59 matt
126 ; Added checking for dest==src for several functions where this is not allowed
128 ; Revision 1.21 1994/01/19 23:13:02 matt
129 ; Fixed bug in vm_vec_ang_2_matrix()
131 ; Revision 1.20 1994/01/04 12:33:43 mike
132 ; Prevent divide overflow in vm_vec_scale2
134 ; Revision 1.19 1993/12/21 19:46:26 matt
135 ; Added function vm_dist_to_plane()
137 ; Revision 1.18 1993/12/13 17:26:23 matt
138 ; Added vm_vec_dist()
140 ; Revision 1.17 1993/12/02 12:43:39 matt
141 ; New functions: vm_vec_copy_scale(), vm_vec_scale2()
143 ; Revision 1.16 1993/10/29 22:39:29 matt
144 ; Changed matrix order, making direction vectors the rows
146 ; Revision 1.15 1993/10/29 18:06:01 matt
147 ; Fixed vm_vector_2_matrix() bug when forward vector was straight down
149 ; Revision 1.14 1993/10/26 18:51:26 matt
150 ; Fixed some register trashes in vm_vec_ang_2_matrix()
152 ; Revision 1.13 1993/10/25 11:49:37 matt
153 ; Made vm_vec_delta_ang() take optional forward vector to return signed delta
155 ; Revision 1.12 1993/10/20 01:09:42 matt
156 ; Added vm_vec_delta_ang(), vm_vec_delta_ang_norm(), and vm_vec_ang_2_matrix()
158 ; Revision 1.11 1993/10/17 17:03:08 matt
159 ; vm_vector_2_matrix() now takes optional right vector
161 ; Revision 1.10 1993/10/10 18:11:42 matt
162 ; Changed angles_2_matrix so that heading & bank rotate in the
163 ; correct directions.
165 ; Revision 1.9 1993/09/30 16:17:59 matt
166 ; Fixed bug in vector_2_matrix() by adding another normalize
168 ; Revision 1.8 1993/09/29 10:51:58 matt
169 ; Fixed bad register trashes in crossprod, perp, & normal
171 ; Revision 1.7 1993/09/28 12:16:46 matt
172 ; Fixed bugs in cross product
173 ; Added func vm_vector_2_matrix()
175 ; Revision 1.6 1993/09/24 21:19:37 matt
176 ; Added vm_vec_avg() and vm_vec_avg4()
178 ; Revision 1.5 1993/09/20 18:15:07 matt
179 ; Trap zero-length vectors in vm_vec_normalize(), vm_vec_perp(), and vm_vec_normal()
181 ; Revision 1.4 1993/09/20 14:56:43 matt
182 ; Fixed bug in vm_vec_normal(), made that routine normalize the results,
183 ; and added new function vm_vec_perp().
185 ; Revision 1.3 1993/09/20 10:12:06 mike
188 ; Revision 1.2 1993/09/17 11:10:33 matt
189 ; Added vm_vec_add2() and vm_vec_sub2(), which take 2 args (dest==src0)
191 ; Revision 1.1 1993/09/16 20:10:24 matt
202 ; Cater for linux ELF compilers which don't prefix underscores...
204 %define _vmd_zero_vector vmd_zero_vector
205 %define _vmd_identity_matrix vmd_identity_matrix
207 %define _vm_vec_add vm_vec_add
208 %define _vm_vec_sub vm_vec_sub
209 %define _vm_vec_add2 vm_vec_add2
210 %define _vm_vec_sub2 vm_vec_sub2
211 %define _vm_vec_avg vm_vec_avg
212 %define _vm_vec_scale vm_vec_scale
213 %define _vm_vec_copy_scale vm_vec_copy_scale
214 %define _vm_vec_scale2 vm_vec_scale2
215 %define _vm_vec_scale_add vm_vec_scale_add
216 %define _vm_vec_scale_add2 vm_vec_scale_add2
217 %define _vm_vec_mag vm_vec_mag
218 %define _vm_vec_dist vm_vec_dist
219 %define _vm_vec_mag_quick vm_vec_mag_quick
220 %define _vm_vec_dist_quick vm_vec_dist_quick
221 %define _vm_vec_normalize vm_vec_normalize
222 %define _vm_vec_normalize_quick vm_vec_normalize_quick
223 %define _vm_vec_normalized_dir vm_vec_normalized_dir
224 %define _vm_vec_normalized_dir_quick vm_vec_normalized_dir_quick
225 %define _vm_vec_copy_normalize vm_vec_copy_normalize
226 %define _vm_vec_copy_normalize_quick vm_vec_copy_normalize_quick
227 %define _vm_vec_dotprod vm_vec_dotprod
228 %define _vm_vec_crossprod vm_vec_crossprod
229 %define _vm_vec_perp vm_vec_perp
230 %define _vm_vec_normal vm_vec_normal
231 %define _vm_vec_rotate vm_vec_rotate
232 %define _vm_vec_delta_ang vm_vec_delta_ang
233 %define _vm_vec_delta_ang_norm vm_vec_delta_ang_norm
234 %define _vm_vector_2_matrix vm_vector_2_matrix
235 %define _vm_vec_ang_2_matrix vm_vec_ang_2_matrix
236 %define _vm_angles_2_matrix vm_angles_2_matrix
237 %define _vm_transpose_matrix vm_transpose_matrix
238 %define _vm_copy_transpose_matrix vm_copy_transpose_matrix
239 %define _vm_matrix_x_matrix vm_matrix_x_matrix
244 ;temporary vectors for surface normal calculation
254 ;sine & cosine values for angles_2_matrix
262 global _vmd_zero_vector,_vmd_identity_matrix
264 ;These should never be changed!
268 _vmd_identity_matrix:
275 extern fix_sincos_asm
278 ; calling convention is arguments on stack from right to left,
279 ; eax,ecx,edx possibly destroyed, ebx,esi,edi,ebp preserved,
280 ; caller removes arguments.
287 global _vm_vec_copy_scale
288 global _vm_vec_scale2
289 global _vm_vec_scale_add
290 global _vm_vec_scale_add2
293 global _vm_vec_mag_quick
294 global _vm_vec_dist_quick
295 global _vm_vec_normalize
296 global _vm_vec_normalize_quick
297 global _vm_vec_normalized_dir
298 global _vm_vec_normalized_dir_quick
299 global _vm_vec_copy_normalize
300 global _vm_vec_copy_normalize_quick
301 global _vm_vec_dotprod
302 global _vm_vec_crossprod
304 global _vm_vec_normal
305 global _vm_angles_2_matrix
306 global _vm_vec_rotate
307 global _vm_vec_delta_ang
308 global _vm_vec_delta_ang_norm
309 global _vm_transpose_matrix
310 global _vm_copy_transpose_matrix
311 global _vm_matrix_x_matrix
312 global _vm_vector_2_matrix
313 global _vm_vec_ang_2_matrix
346 ; offsets in fixang struct (packed)
360 ;vector offsets in matrix
365 ; vec *vm_vec_add(vec *dest, vec *src1, vec *src2);
383 ; vec *vm_vec_sub(vec *dest, vec *src1, vec *src2);
401 ; vec *vm_vec_add2(vec *dest, vec *src);
415 ; vec *vm_vec_sub2(vec *dest, vec *src);
429 ; vec *vm_vec_avg(vec *dest, vec *src1, vec *src2);
448 ; vec *vm_vec_scale(vec *dest, fix scale);
466 ; vec *vm_vec_copy_scale(vec *dest, vec *src, fix scale);
487 ; vec *vm_vec_scale_add(vec *dest, vec *src1, vec *src2, fix scale);
489 ; dest=src1+src2*scale
512 ; vec *vm_vec_scale_add2(vec *dest, vec *src, fix scale);
533 ; vec *vm_vec_scale2(vec *dest, fix n, fix d);
558 ;compute magnitude of vector. takes esi=vector, returns eax=mag
585 ;compute the distance between two points. (does sub and mag)
607 call quad_sqrt_asm ; asm version, takes eax,edx
614 ;computes an approximation of the magnitude of a vector
615 ;uses dist = largest + next_largest*3/8 + smallest*3/16
639 mag_quick_eax_ebx_ecx:
644 no_swap_ab: cmp ebx,ecx
651 do_add: sar ebx,2 ; b*1/4
653 add ebx,ecx ; b*1/4 + c*1/8
654 add eax,ebx ;a + b*1/4 + c*1/8
655 sar ebx,1 ; b*1/8 + c*1/16
656 add eax,ebx ;a + b*3/4 + c*3/16
663 ;computes an approximation of the distance between two points.
664 ;uses dist = largest + next_largest*3/8 + smallest*3/16
691 jmp mag_quick_eax_ebx_ecx
694 ;return the normalized direction vector between two points
695 ;dest = normalized(end - start).
696 ;takes edi=dest, esi=endpoint, ebx=startpoint. Returns mag of dir vec
697 ;NOTE: the order of the parameters matches the vector subtraction
698 _vm_vec_normalized_dir:
730 mov ecx,eax ;mag in ecx
749 ;normalize a vector in place.
757 jmp vm_vec_copy_normalize_nopar
759 ;normalize a vector. takes edi=dest, esi=vector
760 ;returns ecx=mag of source vec
761 _vm_vec_copy_normalize:
767 vm_vec_copy_normalize_nopar:
786 mov ecx,eax ;mag in ecx
804 ;normalize a vector in place.
806 _vm_vec_normalize_quick:
811 jmp vm_vec_copy_normalize_quick_nopar
813 ;save as vm_vec_normalized_dir, but with quick sqrt
814 ;takes dest, endpoint, startpoint. Returns mag of dir vec
815 _vm_vec_normalized_dir_quick:
829 jmp vm_vec_copy_normalize_quick_nopar
833 _vm_vec_copy_normalize_quick:
839 vm_vec_copy_normalize_quick_nopar:
841 call _vm_vec_mag_quick
844 mov ecx,eax ;mag in ecx
862 ;compute dot product of two vectors. takes esi,edi=vectors, returns eax=dotprod
887 ;ifndef NDEBUG ;check for overflow
888 ;always do overflow check, and return saturated value
889 sar edx,16 ;get real sign from high word
891 cdq ;get sign of our result
892 cmp bx,dx ;same sign?
894 ;;debug_brk 'overflow in vm_vec_dotprod'
896 or ebx,ebx ;check desired sign
907 ;computes cross product of two vectors.
908 ;Note: this magnitude of the resultant vector is the
909 ;product of the magnitudes of the two source vectors. This means it is
910 ;quite easy for this routine to overflow and underflow. Be careful that
912 ; takes dest, src vectors
924 break_if e,'crossprod: dest==src0'
926 break_if e,'crossprod: dest==src1'
938 %ifndef NDEBUG ;check for overflow
940 cdq ;get sign of result
941 shr ebx,16 ;get high 16 of quad result
942 cmp dx,bx ;sign extension the same?
943 break_if ne,'overflow in crossprod'
956 %ifndef NDEBUG ;check for overflow
958 cdq ;get sign of result
959 shr ebx,16 ;get high 16 of quad result
960 cmp dx,bx ;sign extension the same?
961 break_if ne,'overflow in crossprod'
974 %ifndef NDEBUG ;check for overflow
976 cdq ;get sign of result
977 shr ebx,16 ;get high 16 of quad result
978 cmp dx,bx ;sign extension the same?
979 break_if ne,'overflow in crossprod'
983 mov eax,ebp ;return dest in eax
992 ;computes surface normal from three points. takes ebx=dest, eax,esi,edi=vecs
993 ;returns eax=dest. Result vector is normalized.
995 push dword [esp+16+00];src2
996 push dword [esp+12+04];src1
997 push dword [esp+08+08];src0
998 push dword [esp+04+12];dest
999 call _vm_vec_perp ;get unnormalized
1002 call _vm_vec_normalize
1007 ;make sure a vector is reasonably sized to go into a cross product
1008 ;takes vector in esi
1009 ;trashes eax,ebx,cl,edx
1022 xor cl,cl ;init shift count
1024 test ebx,0fffc0000h ;too big
1026 check_4_down: test ebx,000f00000h
1031 check_2_down: test ebx,0fffc0000h
1038 sar dword [esi+4],cl
1039 sar dword [esi+8],cl
1043 not_too_big: test ebx,0ffff8000h
1045 check_4_up: test ebx,0fffff000h
1050 check_2_up: test ebx,0ffff8000h
1057 sal dword [esi+4],cl
1058 sal dword [esi+8],cl
1063 ; debug_brk commented out by mk on 05/04/94
1064 ;** debug_brk "null vector in check_vec"
1068 ;computes surface normal from three points. takes ebx=dest, eax,esi,edi=vecs
1069 ;returns eax=dest. Result vector is NOT normalized, but this routine does
1070 ;make an effort that cross product does not overflow or underflow
1076 mov ebx,[esp+20] ;src0
1077 mov ecx,[esp+24] ;src1
1078 mov edx,[esp+28] ;src2
1082 %assign i 0 ;tempv1=src2-src1
1089 %assign i 0 ;tempv0=src1-src0
1096 ; esi=tempv0, edi=tempv1
1097 call check_vec ;make sure reasonable value
1099 call check_vec ;make sure reasonable value
1100 ; edi=tempv0, esi=tempv1
1103 push dword [esp+16+8] ;dest
1104 call _vm_vec_crossprod
1113 ;compute a rotation matrix from three angles. takes edi=dest matrix,
1114 ;esi=angles vector. returns dest matrix.
1115 _vm_angles_2_matrix:
1119 mov edi,[esp+16];dest
1120 mov esi,[esp+20];angles
1122 ;get sines & cosines
1138 ;alternate entry point with sines & cosines already computed.
1139 ;Note all the registers already pushed.
1142 ;now calculate the 9 elements
1146 mov ecx,eax ;save sbsh
1151 mov esi,eax ;save cbch
1153 mov [edi+m1],eax ;m1=cbch+sbspsh
1155 mov eax,esi ;get cbch
1157 add eax,ecx ;add sbsh
1158 mov [edi+m8],eax ;m8=sbsh+cbchsp
1163 mov ecx,eax ;save cbsh
1168 mov esi,eax ;save sbch
1170 mov [edi+m2],ebx ;m2=cbshsp-sbch
1172 mov eax,esi ;get sbch
1174 sub eax,ecx ;sub from cbsh
1175 mov [edi+m7],eax ;m7=sbchsp-cbsh
1180 mov [edi+m3],eax ;m3=shcp
1184 mov [edi+m4],eax ;m4=sbcp
1188 mov [edi+m5],eax ;m5=cbcp
1192 mov [edi+m6],eax ;m6=-sp
1196 mov [edi+m9],eax ;m9=chcp
1215 ;create a rotation matrix from one or two vectors.
1216 ;requires forward vec, and assumes zero bank if up & right vecs==NULL
1217 ;up/right vector need not be exactly perpendicular to forward vec
1218 ;takes edi=matrix, esi=forward vec, eax=up vec, ebx=right vec.
1219 ;returns edi=matrix. trashes eax,ebx,esi
1220 ;Note: this routine loses precision as the forward vector approaches
1221 ;straigt up or down (I think)
1222 _vm_vector_2_matrix:
1227 mov esi,[esp+20];fvec
1228 mov eax,[esp+24];uvec
1229 mov ebx,[esp+28];rvec
1233 break_if z,"vm_vector_2_matrix: forward vec cannot be NULL!"
1236 or eax,eax ;up vector present?
1237 jnz near use_up_vec ;..yep
1239 or ebx,ebx ;right vector present?
1240 jz near just_forward_vec ;..nope
1242 push edi ;save matrix
1246 call _vm_vec_copy_normalize
1253 call _vm_vec_copy_normalize
1258 push dword xvec;src1
1259 push dword zvec;src0
1260 push dword yvec;dest
1261 call _vm_vec_crossprod ;get y = z cross x
1264 ;normalize new perpendicular vector
1265 push eax ;get new vec (up) in esi
1266 call _vm_vec_normalize
1271 ;now recompute right vector, in case it wasn't entirely perpendiclar
1273 push dword zvec;src1
1274 push dword yvec;src0
1275 push dword xvec;dest
1276 call _vm_vec_crossprod ;x = y cross z
1279 pop edi ;get matrix back
1281 jmp copy_into_matrix
1284 ;one of the non-forward vectors caused a problem, so ignore them and
1285 ;use just the forward vector
1290 jmp just_forward_vec_norm
1292 ;use forward and up vectors
1294 push edi ;save matrix
1298 call _vm_vec_copy_normalize
1305 call _vm_vec_copy_normalize
1310 push dword zvec;src1
1311 push dword yvec;src0
1312 push dword xvec;dest
1313 call _vm_vec_crossprod ;get x = y cross z
1316 ;normalize new perpendicular vector
1317 push eax ;get new vec (up) in esi
1318 call _vm_vec_normalize
1323 ;now recompute right vector, in case it wasn't entirely perpendiclar
1325 push dword xvec;src1
1326 push dword zvec;src0
1327 push dword yvec;dest
1328 call _vm_vec_crossprod ;y = z cross x
1331 pop edi ;get matrix back
1334 vm_copy edi+rvec,xvec
1335 vm_copy edi+uvec,yvec
1336 vm_copy edi+fvec,zvec
1350 debug_brk '0-len vec in vec_2_mat'
1353 ;only the forward vector is present
1358 call _vm_vec_copy_normalize
1362 just_forward_vec_norm:
1365 or eax,[esi+8] ;check both x & z == 0
1368 ;forward vector is straight up (or down)
1370 mov dword [edi+m1],f1_0
1371 mov eax,[esi+4] ;get y componant
1375 sub eax,edx ;make sign correct
1387 m2m_neg [edi+8],[esi+0]
1389 call _vm_vec_normalize
1396 call _vm_vec_crossprod
1407 ;multiply (dot) two vectors. assumes dest ptr in ebp, src pointers in esi,edi.
1408 ;trashes ebx,ecx,edx
1411 ;macro dest,x0,y0,z0,x1,y1,z1
1427 shrd ebx,ecx,16 ;fixup ebx
1432 ;rotate a vector by a rotation matrix
1433 ;eax=dest vector, esi=src vector, edi=matrix. returns eax=dest vector
1437 break_if e,'vec_rotate: dest==src'
1443 mov ebp,[esp+20];dest vec
1444 mov esi,[esp+24];src vec
1445 mov edi,[esp+28];matrix
1448 vv_mul 0, 0,4,8, m1,m4,m7
1449 vv_mul 4, 0,4,8, m2,m5,m8
1450 vv_mul 8, 0,4,8, m3,m6,m9
1452 mov eax,ebp ;return eax=dest
1460 ;transpose a matrix in place. Takes matrix. returns matrix
1461 _vm_transpose_matrix:
1480 ;copy and transpose a matrix. Takes edi=dest, esi=src. returns edi=dest
1481 _vm_copy_transpose_matrix:
1482 mov edx,[esp+4];dest
1516 ;mulitply 2 matrices, fill in dest. returns ptr to dest
1517 ;takes dest, src0, scr1
1518 _vm_matrix_x_matrix:
1521 break_if e,'matrix_x_matrix: dest==src0'
1523 break_if e,'matrix_x_matrix: dest==src1'
1529 mov ebp,[esp+20] ;ebp=dest
1530 mov esi,[esp+24] ;esi=src0
1531 mov edi,[esp+28] ;edi=src1
1533 ;;This code would do the same as the nine lines below it, but I'm sure
1534 ;;Mike would disapprove
1535 ;; for s0,<<m1,m2,m3>,<m4,m5,m6>,<m7,m8,m9>>
1536 ;; for s1,<<m1,m4,m7>,<m2,m5,m8>,<m3,m6,m9>>
1537 ;; vv_mul @ArgI(1,s0)+@ArgI(1,s1), s0, s1
1541 vv_mul m1, m1,m2,m3, m1,m4,m7
1542 vv_mul m2, m1,m2,m3, m2,m5,m8
1543 vv_mul m3, m1,m2,m3, m3,m6,m9
1545 vv_mul m4, m4,m5,m6, m1,m4,m7
1546 vv_mul m5, m4,m5,m6, m2,m5,m8
1547 vv_mul m6, m4,m5,m6, m3,m6,m9
1549 vv_mul m7, m7,m8,m9, m1,m4,m7
1550 vv_mul m8, m7,m8,m9, m2,m5,m8
1551 vv_mul m9, m7,m8,m9, m3,m6,m9
1553 mov eax,ebp ;eax=ptr to dest
1560 ;computes the delta angle between two vectors
1561 ;two entry points: normalized and non-normalized vectors
1562 ;takes esi,edi=vectors, eax=optional forward vector
1563 ;returns ax=delta angle
1564 ;if the forward vector is NULL, the absolute values of the delta angle
1565 ;is returned. If it is specified, the rotation around that vector from
1566 ;esi to edi is returned.
1576 call _vm_vec_normalize
1579 call _vm_vec_normalize
1583 _vm_vec_delta_ang_norm:
1592 call _vm_vec_dotprod
1594 call fix_acos_asm ;now angle in ax
1595 mov ebx,[esp+24] ;get forward vec
1598 ;do cross product to find sign of angle
1599 push eax ;save angle
1603 push dword tempv0 ;new vec
1604 call _vm_vec_crossprod
1606 push ebx ;forward vec
1607 push eax ;new vector
1608 call _vm_vec_dotprod ;eax=dotprod
1614 sub eax,edx ;make sign correct
1622 ;compute a rotation matrix from the forward vector and a rotation around
1623 ;that vector. takes esi=vector, ax=angle, edi=matrix. returns edi=dest matrix.
1625 _vm_vec_ang_2_matrix:
1638 ;extract heading & pitch from vector
1640 mov eax,[esi+4] ;m6=-sp
1646 call long_sqrt_asm ;eax=cp
1662 ;compute the distance from a point to a plane. takes the normalized normal
1663 ;of the plane (ebx), a point on the plane (edi), and the point to check (esi).
1664 ;returns distance in eax
1665 ;distance is signed, so negative dist is on the back of the plane
1670 call vm_vec_sub ;vecs in esi,edi
1672 mov esi,eax ;vector plane -> point
1679 ;extract the angles from a matrix. takes esi=matrix, fills in edi=angvec
1680 vm_extract_angles_matrix:
1681 pushm eax,ebx,edx,ecx
1683 ;extract heading & pitch from forward vector
1685 mov eax,[esi].fvec.z ;ch
1686 mov ebx,[esi].fvec.x ;sh
1688 mov ecx,ebx ;check for z==x==0
1690 jz zero_head ;zero, use head=0
1692 zero_head: mov [edi].head,ax ;save heading
1694 call fix_sincos_asm ;get back sh
1698 mov ecx,eax ;save abs(sine)
1701 cmp eax,ecx ;which is larger?
1702 pop eax ;get sine back
1705 ;sine is larger, so use it
1706 mov ebx,eax ;ebx=sine heading
1707 mov eax,[esi].m3 ;cp = shcp / sh
1710 ;cosine is larger, so use it
1713 mov eax,[esi].fvec.z ;get chcp
1714 get_cosp: fixdiv ebx ;cp = chcp / ch
1720 mov ebx,[esi].fvec.y ;fvec.y = -sp
1721 neg ebx ;ebx = y (sin)
1722 mov ecx,ebx ;check for z==x==0
1724 jz zero_pitch ;bogus vec, set p=0
1726 zero_pitch: mov [edi].pitch,ax
1731 mov eax,[esi].m4 ;m4 = sbcp
1733 mov ebx,eax ;save sb
1735 mov eax,[esi].m5 ;get cbcp
1737 mov ecx,ebx ;check for z==x==0
1739 jz zero_bank ;bogus vec, set n=0
1741 zero_bank: mov [edi].bank,ax
1744 popm eax,ebx,edx,ecx
1748 ;the cosine of pitch is zero. we're pitched straight up. say no bank
1749 cp_zero: mov [edi].bank,0 ;no bank
1751 popm eax,ebx,edx,ecx
1755 ;extract the angles from a vector, assuming zero bank.
1756 ;takes esi=vec, edi=angvec
1757 ;note versions for normalized and not normalized vector
1758 ;unnormalized version TRASHES ESI
1759 vm_extract_angles_vector:
1762 call vm_vec_copy_normalize ;ecx=mag
1767 vm_extract_angles_vector_normalized:
1770 mov [edi].bank,0 ;always zero bank
1775 mov [edi].pitch,ax ;p = asin(-y)
1780 jz zero_head2 ;check for up vector
1782 mov ebx,[esi].x ;get x again
1784 zero_head2: mov [edi].head,ax ;h = atan2(x,z) (or zero)