--- ray/src/common/image.c	2008/12/12 22:05:38	2.35
+++ ray/src/common/image.c	2013/03/24 19:40:26	2.39
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: image.c,v 2.35 2008/12/12 22:05:38 greg Exp $";
+static const char	RCSid[] = "$Id: image.c,v 2.39 2013/03/24 19:40:26 greg Exp $";
 #endif
 /*
  *  image.c - routines for image generation.
@@ -33,7 +33,8 @@ VIEW  *v
 	static char  ill_horiz[] = "illegal horizontal view size";
 	static char  ill_vert[] = "illegal vertical view size";
 	
-	if (v->vaft < -FTINY || (v->vaft > FTINY && v->vaft <= v->vfore))
+	if ((v->vfore < -FTINY) | (v->vaft < -FTINY) ||
+			(v->vaft > FTINY) & (v->vaft <= v->vfore))
 		return("illegal fore/aft clipping plane");
 
 	if (v->vdist <= FTINY)
@@ -221,9 +222,8 @@ double  y
 		y *= sqrt(v->vn2);
 		d = x*x + y*y;
 		z = (1. - d)/(1. + d);
-		d = d <= FTINY*FTINY ? PI : sqrt((1.0 - z*z)/d);
-		x *= d;
-		y *= d;
+		x *= (1. + z);
+		y *= (1. + z);
 		direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
 		direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
 		direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
@@ -308,9 +308,8 @@ FVECT  p
 			return;
 		if (d <= -(1.0-FTINY))
 			return;		/* really an error */
-		d = sqrt(1.0 - d*d) / (1.0 + d);
-		ip[0] += DOT(disp,v->hvec)*d/sqrt(v->hn2);
-		ip[1] += DOT(disp,v->vvec)*d/sqrt(v->vn2);
+		ip[0] += DOT(disp,v->hvec)/((1. + d)*sqrt(v->hn2));
+		ip[1] += DOT(disp,v->vvec)/((1. + d)*sqrt(v->vn2));
 		return;
 	}
 	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
@@ -326,7 +325,7 @@ int  px,
 int  py
 )
 {
-	register int  x, y;
+	int  x, y;
 
 	if (rp->rt & YMAJOR) {
 		x = px;
@@ -352,10 +351,11 @@ double  lx,
 double  ly
 )
 {
-	register int  x, y;
+	int  x, y;
 
-	x = lx * rp->xr;
-	y = ly * rp->yr;
+	x = (int)(lx*rp->xr + .5 - (lx < 0.0));
+	y = (int)(ly*rp->yr + .5 - (ly < 0.0));
+
 	if (rp->rt & XDECR)
 		x = rp->xr-1 - x;
 	if (rp->rt & YDECR)
@@ -498,7 +498,7 @@ VIEW  *vp
 )
 {
 	static char  vwstr[128];
-	register char  *cp = vwstr;
+	char  *cp = vwstr;
 
 	*cp = '\0';
 	if (vp->type != stdview.type) {
@@ -557,8 +557,8 @@ char  *s
 {
 	static char  *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
 	extern char  *progname;
-	register char  *cp;
-	register char  **an;
+	char  *cp;
+	char  **an;
 					/* add program name to list */
 	if (altname[0] == NULL) {
 		for (cp = progname; *cp; cp++)