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Several objects share a common style of representing vertices with optional per-vertex surface-normal and color. All vertices within an object have the same format, specified by the header key word.
All data for a vertex is grouped together (as opposed to e.g. giving coordinates for all vertices, then colors for all vertices, and so on).
The syntax for N-dimensional vertices (N > 3) is
4
modifier
has been specified in the object's header line)
Note, howerver, that N-dimensional objects internally always have
(N+1)-dimensional points; the first component x[0] – if
present in the object file – is used as homogeneous divisor. This is
different from the ordinary 3D case where the 4
modifier
generates a 4D object where the homogeneous component implicitly is set
to 1.
Color components usually can be specified like for 3D vertices, see Vertices, while specifying normals does not make sense.