--- ray/src/common/xf.c	1989/03/24 17:10:43	1.3
+++ ray/src/common/xf.c	2003/02/25 02:47:22	2.5
@@ -1,33 +1,38 @@
-/* Copyright (c) 1986 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: xf.c,v 2.5 2003/02/25 02:47:22 greg Exp $";
 #endif
-
 /*
  *  xf.c - routines to convert transform arguments into 4X4 matrix.
  *
- *     1/28/86
+ *  External symbols declared in standard.h
  */
 
+#include "copyright.h"
 
-#define  PI		3.14159265358979323846
+#include  "standard.h"
 
-#define  checkarg(a,n)	if (strcmp(av[i],a) || i+n >= ac) return(i)
+#define  d2r(a)		((PI/180.)*(a))
 
+#define  checkarg(a,l)	if (av[i][a] || badarg(ac-i-1,av+i+1,l)) goto done
 
+
 int
-xf(xfmat, xfsca, ac, av)		/* get transform specification */
-double  xfmat[4][4];
-double  *xfsca;
+xf(ret, ac, av)			/* get transform specification */
+register XF  *ret;
 int  ac;
 char  *av[];
 {
-	double  atof(), sin(), cos();
-	double  m4[4][4];
-	double  theta;
-	int  i;
+	MAT4  xfmat, m4;
+	double  xfsca, dtmp;
+	int  i, icnt;
 
+	setident4(ret->xfm);
+	ret->sca = 1.0;
+
+	icnt = 1;
+	setident4(xfmat);
+	xfsca = 1.0;
+
 	for (i = 0; i < ac && av[i][0] == '-'; i++) {
 	
 		setident4(m4);
@@ -35,7 +40,7 @@ char  *av[];
 		switch (av[i][1]) {
 	
 		case 't':			/* translate */
-			checkarg("-t",3);
+			checkarg(2,"fff");
 			m4[3][0] = atof(av[++i]);
 			m4[3][1] = atof(av[++i]);
 			m4[3][2] = atof(av[++i]);
@@ -44,81 +49,104 @@ char  *av[];
 		case 'r':			/* rotate */
 			switch (av[i][2]) {
 			case 'x':
-				checkarg("-rx",1);
-				theta = PI/180.0 * atof(av[++i]);
-				m4[1][1] = m4[2][2] = cos(theta);
-				m4[2][1] = -(m4[1][2] = sin(theta));
+				checkarg(3,"f");
+				dtmp = d2r(atof(av[++i]));
+				m4[1][1] = m4[2][2] = cos(dtmp);
+				m4[2][1] = -(m4[1][2] = sin(dtmp));
 				break;
 			case 'y':
-				checkarg("-ry",1);
-				theta = PI/180.0 * atof(av[++i]);
-				m4[0][0] = m4[2][2] = cos(theta);
-				m4[0][2] = -(m4[2][0] = sin(theta));
+				checkarg(3,"f");
+				dtmp = d2r(atof(av[++i]));
+				m4[0][0] = m4[2][2] = cos(dtmp);
+				m4[0][2] = -(m4[2][0] = sin(dtmp));
 				break;
 			case 'z':
-				checkarg("-rz",1);
-				theta = PI/180.0 * atof(av[++i]);
-				m4[0][0] = m4[1][1] = cos(theta);
-				m4[1][0] = -(m4[0][1] = sin(theta));
+				checkarg(3,"f");
+				dtmp = d2r(atof(av[++i]));
+				m4[0][0] = m4[1][1] = cos(dtmp);
+				m4[1][0] = -(m4[0][1] = sin(dtmp));
 				break;
 			default:
-				return(i);
+				goto done;
 			}
 			break;
 
 		case 's':			/* scale */
-			checkarg("-s",1);
-			*xfsca *=
+			checkarg(2,"f");
+			dtmp = atof(av[i+1]);
+			if (dtmp == 0.0) goto done;
+			i++;
+			xfsca *=
 			m4[0][0] = 
 			m4[1][1] = 
-			m4[2][2] = atof(av[++i]);
+			m4[2][2] = dtmp;
 			break;
 
 		case 'm':			/* mirror */
 			switch (av[i][2]) {
 			case 'x':
-				checkarg("-mx",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[0][0] = -1.0;
 				break;
 			case 'y':
-				checkarg("-my",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[1][1] = -1.0;
 				break;
 			case 'z':
-				checkarg("-mz",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[2][2] = -1.0;
 				break;
 			default:
-				return(i);
+				goto done;
 			}
 			break;
 
+		case 'i':			/* iterate */
+			checkarg(2,"i");
+			while (icnt-- > 0) {
+				multmat4(ret->xfm, ret->xfm, xfmat);
+				ret->sca *= xfsca;
+			}
+			icnt = atoi(av[++i]);
+			setident4(xfmat);
+			xfsca = 1.0;
+			continue;
+
 		default:
-			return(i);
+			goto done;
 
 		}
 		multmat4(xfmat, xfmat, m4);
 	}
+done:
+	while (icnt-- > 0) {
+		multmat4(ret->xfm, ret->xfm, xfmat);
+		ret->sca *= xfsca;
+	}
 	return(i);
 }
 
 
-#ifdef  INVXF
 int
-invxf(xfmat, xfsca, ac, av)		/* invert transform specification */
-double  xfmat[4][4];
-double  *xfsca;
+invxf(ret, ac, av)		/* invert transform specification */
+register XF  *ret;
 int  ac;
 char  *av[];
 {
-	double  atof(), sin(), cos();
-	double  m4[4][4];
-	double  theta;
-	int  i;
+	MAT4  xfmat, m4;
+	double  xfsca, dtmp;
+	int  i, icnt;
 
+	setident4(ret->xfm);
+	ret->sca = 1.0;
+
+	icnt = 1;
+	setident4(xfmat);
+	xfsca = 1.0;
+
 	for (i = 0; i < ac && av[i][0] == '-'; i++) {
 	
 		setident4(m4);
@@ -126,7 +154,7 @@ char  *av[];
 		switch (av[i][1]) {
 	
 		case 't':			/* translate */
-			checkarg("-t",3);
+			checkarg(2,"fff");
 			m4[3][0] = -atof(av[++i]);
 			m4[3][1] = -atof(av[++i]);
 			m4[3][2] = -atof(av[++i]);
@@ -135,64 +163,93 @@ char  *av[];
 		case 'r':			/* rotate */
 			switch (av[i][2]) {
 			case 'x':
-				checkarg("-rx",1);
-				theta = -PI/180.0 * atof(av[++i]);
-				m4[1][1] = m4[2][2] = cos(theta);
-				m4[2][1] = -(m4[1][2] = sin(theta));
+				checkarg(3,"f");
+				dtmp = -d2r(atof(av[++i]));
+				m4[1][1] = m4[2][2] = cos(dtmp);
+				m4[2][1] = -(m4[1][2] = sin(dtmp));
 				break;
 			case 'y':
-				checkarg("-ry",1);
-				theta = -PI/180.0 * atof(av[++i]);
-				m4[0][0] = m4[2][2] = cos(theta);
-				m4[0][2] = -(m4[2][0] = sin(theta));
+				checkarg(3,"f");
+				dtmp = -d2r(atof(av[++i]));
+				m4[0][0] = m4[2][2] = cos(dtmp);
+				m4[0][2] = -(m4[2][0] = sin(dtmp));
 				break;
 			case 'z':
-				checkarg("-rz",1);
-				theta = -PI/180.0 * atof(av[++i]);
-				m4[0][0] = m4[1][1] = cos(theta);
-				m4[1][0] = -(m4[0][1] = sin(theta));
+				checkarg(3,"f");
+				dtmp = -d2r(atof(av[++i]));
+				m4[0][0] = m4[1][1] = cos(dtmp);
+				m4[1][0] = -(m4[0][1] = sin(dtmp));
 				break;
 			default:
-				return(i);
+				goto done;
 			}
 			break;
 
 		case 's':			/* scale */
-			checkarg("-s",1);
-			*xfsca *=
+			checkarg(2,"f");
+			dtmp = atof(av[i+1]);
+			if (dtmp == 0.0) goto done;
+			i++;
+			xfsca *=
 			m4[0][0] = 
 			m4[1][1] = 
-			m4[2][2] = 1.0 / atof(av[++i]);
+			m4[2][2] = 1.0 / dtmp;
 			break;
 
 		case 'm':			/* mirror */
 			switch (av[i][2]) {
 			case 'x':
-				checkarg("-mx",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[0][0] = -1.0;
 				break;
 			case 'y':
-				checkarg("-my",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[1][1] = -1.0;
 				break;
 			case 'z':
-				checkarg("-mz",0);
-				*xfsca *=
+				checkarg(3,"");
+				xfsca *=
 				m4[2][2] = -1.0;
 				break;
 			default:
-				return(i);
+				goto done;
 			}
 			break;
 
+		case 'i':			/* iterate */
+			checkarg(2,"i");
+			while (icnt-- > 0) {
+				multmat4(ret->xfm, xfmat, ret->xfm);
+				ret->sca *= xfsca;
+			}
+			icnt = atoi(av[++i]);
+			setident4(xfmat);
+			xfsca = 1.0;
+			break;
+
 		default:
-			return(i);
+			goto done;
 
 		}
 		multmat4(xfmat, m4, xfmat);	/* left multiply */
 	}
+done:
+	while (icnt-- > 0) {
+		multmat4(ret->xfm, xfmat, ret->xfm);
+		ret->sca *= xfsca;
+	}
 	return(i);
 }
-#endif
+
+
+int
+fullxf(fx, ac, av)			/* compute both forward and inverse */
+FULLXF  *fx;
+int  ac;
+char  *av[];
+{
+	xf(&fx->f, ac, av);
+	return(invxf(&fx->b, ac, av));
+}