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mattias
06-21-2001, 02:57 PM
If lighting is to be enabled, you must calculate normals for the surfaces. But normals are assigned to vertices - how do I assign normals to surfaces?

Should I just make sure the "average normal" from the vertices is the same as the surface normal? (all vertices in a cube will then have a normal in the same direction as one of the diagonals of the cube)

(I know what normals are and how to calculate them.)

zed
06-21-2001, 05:18 PM
the current normal will be applyed to whatever vertices follow it.

eg
normal1
vertex1
vertex2
vertex3
vertex4
vertex5
all 5 vertices above use the same normal. use this to give the appearence of a flat shape for rounded shapes u usually want one normal pervertice ie
normal1
vertex1
normal2
vertex2
normal3
vertex3
normal4
vertex4

BTW with vertex arrays u must have one normal per vertex. ie u cant have normals for a face. if u want that u will have to repeat some normals eg
normal1
vertex1
normal1
vertex2
normal1
vertex3
normal1
vertex4