--- ray/src/common/mat4.c 1991/06/18 12:01:16 1.6 +++ ray/src/common/mat4.c 2003/02/25 02:47:21 2.4 @@ -1,15 +1,12 @@ -/* Copyright (c) 1990 Regents of the University of California */ - #ifndef lint -static char SCCSid[] = "$SunId$ LBL"; +static const char RCSid[] = "$Id: mat4.c,v 2.4 2003/02/25 02:47:21 greg Exp $"; #endif - /* * mat4.c - routines dealing with 4 X 4 homogeneous transformation matrices. - * - * 10/19/85 */ +#include "copyright.h" + #include "mat4.h" MAT4 m4ident = MAT4IDENT; @@ -17,6 +14,7 @@ MAT4 m4ident = MAT4IDENT; static MAT4 m4tmp; /* for efficiency */ +void multmat4(m4a, m4b, m4c) /* multiply m4b X m4c and put into m4a */ MAT4 m4a; register MAT4 m4b, m4c; @@ -34,6 +32,7 @@ register MAT4 m4b, m4c; } +void multv3(v3a, v3b, m4) /* transform vector v3b by m4 and put into v3a */ FVECT v3a; register FVECT v3b; @@ -49,6 +48,7 @@ register MAT4 m4; } +void multp3(p3a, p3b, m4) /* transform p3b by m4 and put into p3a */ register FVECT p3a; FVECT p3b; @@ -59,61 +59,3 @@ register MAT4 m4; p3a[1] += m4[3][1]; p3a[2] += m4[3][2]; } - - -#ifdef INVMAT -/* - * invmat - computes the inverse of mat into inverse. Returns 1 - * if there exists an inverse, 0 otherwise. It uses Gaussian Elimination - * method with partial pivoting. - */ - -invmat(inverse,mat) -MAT4 mat, inverse; -{ -#define SWAP(a,b,t) (t=a,a=b,b=t) -#define ABS(x) (x>=0?x:-(x)) - - register int i,j,k; - register double temp; - - copymat4(m4tmp, mat); - setident(inverse); - - for(i = 0; i < 4; i++) { - /* Look for row with largest pivot and swap rows */ - temp = 0; j = -1; - for(k = i; k < 4; k++) - if(ABS(m4tmp[k][i]) > temp) { - temp = ABS(m4tmp[k][i]); - j = k; - } - if(j == -1) /* No replacing row -> no inverse */ - return(0); - if (j != i) - for(k = 0; k < 4; k++) { - SWAP(m4tmp[i][k],m4tmp[j][k],temp); - SWAP(inverse[i][k],inverse[j][k],temp); - } - - temp = m4tmp[i][i]; - for(k = 0; k < 4; k++) { - m4tmp[i][k] /= temp; - inverse[i][k] /= temp; - } - for(j = 0; j < 4; j++) { - if(j != i) { - temp = m4tmp[j][i]; - for(k = 0; k < 4; k++) { - m4tmp[j][k] -= m4tmp[i][k]*temp; - inverse[j][k] -= inverse[i][k]*temp; - } - } - } - } - return(1); - -#undef ABS -#undef SWAP -} -#endif