lets say we have a polygon (a quad perhaps)
which has normals predefined (per vertex)

these normals are not necesarilly normal to the face …

now, if we split the polygon as we do in constructing a bsptree how do we generate normals (and texcoordinates) for the new vertices… (the ones we created on account of splitting the polygon)?

Thank you in advance


Because you know, where you split your polygons, you can just interpolate the normals linearly (like phong-shading). At last you have to normalize the interpolated normals. Be aware that you don’t interpolate two opposite normals at halfway and try to normalize that zero-vector!

[This message has been edited by Marc (edited 08-15-2000).]