I've been toying around with C# and Managed DirectX for a bit and I've come across a problem that I'm not sure how to solve... when I setup a vertex buffer and index buffer and then render it using device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, WIDTH * HEIGHT, 0, numberVerts * 6); it renders fine, if I put the vertex buffer and the index buffer in a mesh, then it looks like the index buffer is not being rendered as a TriangleList... basically all triangles connect to the first vertex... as if it was a TriangleFan... Does anyone know if there is a way to set the PrimitiveType for a Mesh? Thanks for your help and let me know if you need to see more code or screenshots of what is wrong.

I do not know how to change the primitive type used by mesh, but I build meshes all the time with triangle lists and they work fine. It could be a problem with the index data itself. Are you using a 16bit or 32bit index? If you are using a 32bit index you must specify the Use32Bit mesh flag on creation.

Sorry, the AP was me.

The index data itself is fine as it renders ok when I do DrawIndexedPrimities... I was able to get it to work with the mesh by increasing the heightfield from 256x256 to 257x257... though performance of the mesh is terrible compared to using a vertex and index buffer... and yes, when I use larger datasets I am using 32bit indexes...

I will have to look into dynamically splitting the landscape into smaller pieces... hopefully that will solve the performance issue...

Thanks for your reply

Marcel Isler
aka GoodFun
aka ShadowHawk