--- ray/src/cv/bsdf2rad.cal	2017/04/11 02:21:37	2.4
+++ ray/src/cv/bsdf2rad.cal	2017/04/11 18:26:55	2.6
@@ -1,4 +1,4 @@
-{ RCSid $Id: bsdf2rad.cal,v 2.4 2017/04/11 02:21:37 greg Exp $ }
+{ RCSid $Id: bsdf2rad.cal,v 2.6 2017/04/11 18:26:55 greg Exp $ }
 {
 	Calculation of false color scale for bsdf2rad.
 
@@ -13,13 +13,14 @@ LONGWIDTH : 1.*DEGREE;
 mylong = atan2(Ny,Nx);
 
 latlong = if(LATWIDTH-mod(Acos(Nz)+LATWIDTH/2,LATSTEP), .05,
-		if(LONGWIDTH-mod(mylong+LONGWIDTH/2,90*DEGREE), .01,
+		if(LONGWIDTH-mod(mylong+LONGWIDTH/2,90*DEGREE), .02,
 		if(LONGWIDTH-mod(mylong+LONGWIDTH/2,LONGSTEP), .3, 1)));
 
 		{ Compute up vector corresponding to sphere position }
-upx = Nx*Ny*(Nz-1);
-upy = Nx*Nx + Ny*Ny*Nz;
-upz = -Ny*(Nx*Nx+Ny*Ny);
+ur2 = Nx*Nx + Ny*Ny;
+upx = Nx*Ny*(Nz - 1);
+upy = if(ur2 - FTINY, Nx*Nx + Ny*Ny*Nz, Nz);
+upz = -Ny*ur2;
 
 interp_arr2`(i,x,f):(i+1-x)*f(i)+(x-i)*f(i+1);
 interp_arr`(x,f):if(x-1,if(f(0)-x,interp_arr2(floor(x),x,f),f(f(0))),f(1));