My terrain generator/viewer is comming along quite nicely now but I have to get it going quicker. So, the next thing to implement is an Octree and Frustrum culling of the triangles in the scene. I understand the maths for this and the concept is simplicity itself BUT how to implement it with the set of Index Vertex Array that the terrain currently uses for rendering?
My Terrain uses a height map generated from a picture. I then create a vertex array containing all the vertexes in this heightmap. Then I create Y index arrays, each with X2 elements in them. They are X2 long because the indexes produce a very nice triangle strip when passed to glDrawArrays.
But, I dont know how to cull these triangles against the frustum. Am I gogin to have to switch to a array of triangles and render these once I have got rid of the ones that cant be seen?
How do I use VA and Frustum Culling at the same time?
Any ideas would be most appreciated.