The command you need is TriangleVertex but for this you need to use the triangle index, not the vertex index. So, to get the 3 verts of a given triangle, you use something like:
Also, maybe this demo I did a ways back might be of interest?
http://www.blitzbasic.com/codearcs/codearcs.php?code=680
v0 = TriangleVertex(surf,tri_index,0) v1 = TriangleVertex(surf,tri_index,1) v2 = TriangleVertex(surf,tri_index,2)
Also, maybe this demo I did a ways back might be of interest?
http://www.blitzbasic.com/codearcs/codearcs.php?code=680