thank jidrobo for this message. i also want to do similar things.
and i tried this:
//============= code begin ========
isosurface{
function {
density { density_file df3 densityfile interpolate 1 }
}
contained_by { box { 0, 1 } }
pigment{rgb <1,0,0>}
}
//============= code end ==========
but errors appeared when parsing, then how to do?
