   Terrain collision help please
  Hi,Im trying to implement collisions for my entities against my terrain. I developed my terrain using the techniques provided here.I have done the following to find out which cell I am currently in within the terrain:int dx = GetPlayerPtr()->GetPosition().m_x - minbounds.x;int dz = GetPlayerPtr()->GetPosition().m_z - minbounds.z;int cellx = dx / stepx;int cellz = dz / stepz;My problem is I cannot seem to think how I can retrieve the height data from the terrain via knowning the cell (I tryed looping through the vertex buffer using a cell count but this seemed to be incorrect). It is probably simple and I just havent realised it yet :(. My terrain uses a heightmap. thx for any helpMike   