Heightmap artifacts

I’m rendering a heightmap as a series of QUAD_STRIPs. When I view the terrain at certain angles, some of the quads seem to be culled for no apparent reason. See this screenshot: http://wireframe.virtualave.net/personal/dandruf.JPG

I’m building the quad strips so that each one shares an edge, so there shouldn’t be any of these “holes”. What is going on?


[This message has been edited by Noah (edited 03-28-2002).]

Are you sure all your quads are planar? Try changing the primitive type two triangle strips and see if the problem goes away.

Yeah, changing it to triangle strips solves it. Thanks.