(x,y,t,&r,&g,&b)

if (abs(x)<abs(y)) {
   s=x; x=y; y=s;
   l=1;
} else {
   l=.6;
}
u=((1/(x*x))+t/5)*-sgn(x);
v=(y/x*-sgn(x))/2+.5;

w=0; h=0; getpicsiz(w,h);
pic(u*w,v*h,r,g,b);

l*=x*x;
if (abs(x)>abs(y)) l/=2;
r*=l;g*=l;b*=l;