Well forget Blitz's loading commands. They're too slow and CPU hogging to be able to stream. You'd have to write your own loading routines and build the meshes up with CreateMesh() AddVertex and AddTriangle, and it still might be slow.
If it's top down, wouldn't it be fairly simple to load the whole city, group the city into "blocks" and HideEntity any "block" which is not in view? You wouldn't really need any fancy occlusion code as long as you grouped the city into cubic areas.
If it's top down, wouldn't it be fairly simple to load the whole city, group the city into "blocks" and HideEntity any "block" which is not in view? You wouldn't really need any fancy occlusion code as long as you grouped the city into cubic areas.