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4.1.4 N-dimensional Vertices

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

`x[1] x[2] x[3] x[4] ...'
(N floating-point vertex coordinates) or
`x[0] x[1] x[2] x[3] x[4] ...'
((N+1) floating-point vertex coordinates, if the 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.