Ah yes there are some other changes that don't have any effect on your problem, important are the following things:

// event for disabled camera rendering
function SnapShot_Event()
{
if(render_view == camera) return 1;
return 0;
}
...
targ_ent.material=SnapShot_mat;

// draw only targ_ent in "view"
view.genius = targ_ent;
set(view, SHOW | NOENT);


Btw. is this
vec_diff(0,targ_ent.x,view.x); // returns the vector pointer
valid, do all appropriate vec commands allow this?