problem in applying frustum culling + LOD

Do anyone have any idea on the problem ? I have been doing a long long time…

Problem Picture

I assume you’re using triangle-strips to draw the terrain? What is the result when you turn LOD / Frustum culling off? You haven’t posted what method of LOD you are using…

Very hard to tell from that picture exactly what is going on, but it looks like a bug in your lod algorithm, where you are generating the triangles. It doesnt look like anything to do with frustum culling.

I am using triangle-fan and what i do is using this idea:
http://www.vis.uni-stuttgart.de/~roettger/data/Papers/TERRAIN.PDF

I have been doing it for 2 months…but still…I can’t solve it…

Would anyone kindly can help me? I am really very helpless…