--- ray/src/common/mat4.c 1989/12/22 09:24:07 1.3 +++ ray/src/common/mat4.c 2003/02/25 02:47:21 2.4 @@ -1,37 +1,23 @@ -/* Copyright (c) 1986 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" -static double m4tmp[4][4]; /* for efficiency */ +#include "mat4.h" -#define copymat4(m4a,m4b) bcopy((char *)m4b,(char *)m4a,sizeof(m4tmp)) +MAT4 m4ident = MAT4IDENT; +static MAT4 m4tmp; /* for efficiency */ -setident4(m4) -double m4[4][4]; -{ - static double ident[4][4] = { - 1.,0.,0.,0., - 0.,1.,0.,0., - 0.,0.,1.,0., - 0.,0.,0.,1., - }; - copymat4(m4, ident); -} - +void multmat4(m4a, m4b, m4c) /* multiply m4b X m4c and put into m4a */ -double m4a[4][4]; -register double m4b[4][4], m4c[4][4]; +MAT4 m4a; +register MAT4 m4b, m4c; { register int i, j; @@ -46,10 +32,11 @@ register double m4b[4][4], m4c[4][4]; } +void multv3(v3a, v3b, m4) /* transform vector v3b by m4 and put into v3a */ -double v3a[3]; -register double v3b[3]; -register double m4[4][4]; +FVECT v3a; +register FVECT v3b; +register MAT4 m4; { m4tmp[0][0] = v3b[0]*m4[0][0] + v3b[1]*m4[1][0] + v3b[2]*m4[2][0]; m4tmp[0][1] = v3b[0]*m4[0][1] + v3b[1]*m4[1][1] + v3b[2]*m4[2][1]; @@ -61,71 +48,14 @@ register double m4[4][4]; } +void multp3(p3a, p3b, m4) /* transform p3b by m4 and put into p3a */ -register double p3a[3]; -double p3b[3]; -register double m4[4][4]; +register FVECT p3a; +FVECT p3b; +register MAT4 m4; { multv3(p3a, p3b, m4); /* transform as vector */ p3a[0] += m4[3][0]; /* translate */ 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) -double mat[4][4],inverse[4][4]; -{ -#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