--- ray/src/gen/gensurf.c	1990/03/02 17:24:02	1.6
+++ ray/src/gen/gensurf.c	1990/07/09 09:55:47	1.9
@@ -1,9 +1,9 @@
-/* Copyright (c) 1989 Regents of the University of California */
-
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
 #endif
 
+/* Copyright (c) 1989 Regents of the University of California */
+
 /*
  *  gensurf.c - program to generate functional surfaces
  *
@@ -34,7 +34,7 @@ int  smooth = 0;		/* apply smoothing? */
 
 char  *modname, *surfname;
 
-double  funvalue(), l_hermite(), l_bezier(), argument();
+double  funvalue(), l_hermite(), l_bezier(), l_bspline(), argument();
 
 typedef struct {
 	FVECT  p;	/* vertex position */
@@ -46,6 +46,7 @@ main(argc, argv)
 int  argc;
 char  *argv[];
 {
+	extern long	eclock;
 	POINT  *row0, *row1, *row2, *rp;
 	int  i, j, m, n;
 	char  stmp[256];
@@ -53,6 +54,7 @@ char  *argv[];
 	varset("PI", PI);
 	funset("hermite", 5, l_hermite);
 	funset("bezier", 5, l_bezier);
+	funset("bspline", 5, l_bspline);
 
 	if (argc < 8)
 		goto userror;
@@ -90,6 +92,7 @@ char  *argv[];
 	row0++; row1++; row2++;
 						/* print header */
 	printhead(argc, argv);
+	eclock = 0;
 						/* initialize */
 	comprow(-1.0/m, row0, n);
 	comprow(0.0, row1, n);
@@ -218,14 +221,25 @@ register POINT  *row;
 int  siz;
 {
 	double  st[2];
+	int  end;
 	register int  i;
-					/* compute one past each end */
+	
+	if (smooth) {
+		i = -1;			/* compute one past each end */
+		end = siz+1;
+	} else {
+		if (s < -FTINY || s > 1.0+FTINY)
+			return;
+		i = 0;
+		end = siz;
+	}
 	st[0] = s;
-	for (i = -1; i <= siz+1; i++) {
+	while (i <= end) {
 		st[1] = (double)i/siz;
 		row[i].p[0] = funvalue(XNAME, 2, st);
 		row[i].p[1] = funvalue(YNAME, 2, st);
 		row[i].p[2] = funvalue(ZNAME, 2, st);
+		i++;
 	}
 }
 
@@ -429,4 +443,17 @@ l_bezier()
 		argument(2) * 3.*t*(1.+t*(-2.+t)) +
 		argument(3) * 3.*t*t*(1.-t) +
 		argument(4) * t*t*t );
+}
+
+
+double
+l_bspline()
+{
+	double  t;
+
+	t = argument(5);
+	return(	argument(1) * (1./6.+t*(-1./2.+t*(1./2.-1./6.*t))) +
+		argument(2) * (2./3.+t*t*(-1.+1./2.*t)) +
+		argument(3) * (1./6.+t*(1./2.+t*(1./2.-1./2.*t))) +
+		argument(4) * (1./6.*t*t*t) );
 }