--- ray/src/common/mat4.c	1989/02/02 10:34:35	1.1
+++ 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;
 	
@@ -46,84 +32,30 @@ 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;
 {
-	register int  i;
+	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];
+	m4tmp[0][2] = v3b[0]*m4[0][2] + v3b[1]*m4[1][2] + v3b[2]*m4[2][2];
 	
-	for (i = 0; i < 3; i++)
-		m4tmp[0][i] = v3b[0]*m4[0][i] +
-			      v3b[1]*m4[1][i] +
-			      v3b[2]*m4[2][i];
-	
 	v3a[0] = m4tmp[0][0];
 	v3a[1] = m4tmp[0][1];
 	v3a[2] = m4tmp[0][2];
 }
 
 
+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 Gause Elimination
- * method.
- */
-
-invmat(inverse,mat)
-double mat[4][4],inverse[4][4];
-{
-#define SWAP(a,b,t) (t=a,a=b,b=t)
-
-	register int i,j,k;
-	register double temp;
-
-	setident4(inverse);
-	copymat4(m4tmp, mat);
-
-	for(i = 0; i < 4; i++) {
-		if(m4tmp[i][i] == 0) {    /* Pivot is zero */
-			/* Look for a raw with pivot != 0 and swap raws */
-			for(j = i + 1; j < 4; j++)
-				if(m4tmp[j][i] != 0) {
-					for( k = 0; k < 4; k++) {
-						SWAP(m4tmp[i][k],m4tmp[j][k],temp);
-						SWAP(inverse[i][k],inverse[j][k],temp);
-						}
-					break;
-					}
-			if(j == 4)	/* No replacing raw -> no inverse */
-				return(0);
-			}
-
-		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);
-}
-#endif