Mapping an image sequence to numbered copies of unwrapped grids.
string path = chs('path');
string name = chs('name');
string end = chs('ending');
int number = prim(0, 'copynum', i@primnum);
string n = sprintf('%04d', number);
string file = path + name + n + end;
vector uvw = vertex(0, 'uv', i@vtxnum);
vector clr = colormap(file, uvw);
v@Cd = clr;