/*From TeXgraph exemples*/
settings.render=0;
import graph3;
import palette;
size(10cm,0);
currentprojection=orthographic(2,-2,2.5);
real f(pair z) {
real u=z.x, v=z.y;
return (u/2+v)/(2+cos(u/2)*sin(v));
}
surface s=surface(f,(0,0),(14,14),50,Spline);
s.colors(palette(s.map(zpart),Gradient(yellow,red)));
draw(s);
if(!is3D())
shipout(bbox(3mm,Fill(black)));