--- ray/src/common/mat4.c	1990/12/15 15:01:38	1.5
+++ ray/src/common/mat4.c	2003/02/22 02:07:22	2.3
@@ -1,33 +1,75 @@
-/* Copyright (c) 1990 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: mat4.c,v 2.3 2003/02/22 02:07:22 greg Exp $";
 #endif
-
 /*
  *  mat4.c - routines dealing with 4 X 4 homogeneous transformation matrices.
+ */
+
+/* ====================================================================
+ * The Radiance Software License, Version 1.0
  *
- *     10/19/85
+ * Copyright (c) 1990 - 2002 The Regents of the University of California,
+ * through Lawrence Berkeley National Laboratory.   All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *         notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *           if any, must include the following acknowledgment:
+ *             "This product includes Radiance software
+ *                 (http://radsite.lbl.gov/)
+ *                 developed by the Lawrence Berkeley National Laboratory
+ *               (http://www.lbl.gov/)."
+ *       Alternately, this acknowledgment may appear in the software itself,
+ *       if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
+ *       and "The Regents of the University of California" must
+ *       not be used to endorse or promote products derived from this
+ *       software without prior written permission. For written
+ *       permission, please contact radiance@radsite.lbl.gov.
+ *
+ * 5. Products derived from this software may not be called "Radiance",
+ *       nor may "Radiance" appear in their name, without prior written
+ *       permission of Lawrence Berkeley National Laboratory.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of Lawrence Berkeley National Laboratory.   For more
+ * information on Lawrence Berkeley National Laboratory, please see
+ * <http://www.lbl.gov/>.
  */
 
 #include  "mat4.h"
 
+MAT4  m4ident = MAT4IDENT;
+
 static MAT4  m4tmp;		/* for efficiency */
 
 
-setident4(m4)
-MAT4  m4;
-{
-	static MAT4  ident = {
-		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 */
 MAT4  m4a;
 register MAT4  m4b, m4c;
@@ -45,6 +87,7 @@ register MAT4  m4b, m4c;
 }
 
 
+void
 multv3(v3a, v3b, m4)	/* transform vector v3b by m4 and put into v3a */
 FVECT  v3a;
 register FVECT  v3b;
@@ -60,6 +103,7 @@ register MAT4  m4;
 }
 
 
+void
 multp3(p3a, p3b, m4)		/* transform p3b by m4 and put into p3a */
 register FVECT  p3a;
 FVECT  p3b;
@@ -70,61 +114,3 @@ 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