What type of interpolation? Linear interpolation between points would require no extra vertices.
That was what I was doing at the outset, but it gives the "stepping" effect.
You may need to implement some sort of variable LOD to get acceptable performance (farther things approximated using far fewer vertices).
That's easier said than done, but I agree that that would be a good idea.
You may also be able to achieve much better performance by reducing the detail expressed via vertices and using a normal map instead. You could also use normal mapping to simulate fancy non-linear interpolation between vertices without more polygons.
I know the basic theory of normal mapping, but not how to actually do it. I had considered that though.
How is the display list being built? You can optimize this much like other OpenGL drawing, using fewer calls is always better, but doubly so from Python. So try to use things like vertex arrays instead of immediate mode calls, etc.
Vertex arrays aren't widely supported, but VBOs are. I can do vertex arrays, but not vertex buffer objects. Thus, the map is being made from quad or triangle strips (can't remember which).
I assume that by "passing pointers" you really mean copying/transforming data. Just passing an array pointer back and forth has basically no cost, so try and arrange your data structures so that they don't need to be transformed to be used by different parts of the program, and in particular steer clear of doing those types of transforms in Python code wherever possible.
Right, that is what I'm doing externally. The height data is precalculated as opengl units, then stored in a separate module. When I run the game, this module is used by Objects.py (which makes the landscape from the data--the only data processed before the game runs) and the main, which then uses it as collision detection.
Presently, this making of the landscape takes some time. Certainly, not as much as making the heightdata on the fly would be, but still some time. Currently, I'm not making/using any normal data, but when I do, it will be slower still. That is why the landscape loader must be in C. By transferring data, I mean sending heightmap data (from the premade .py file) to C, then getting the display list back.
Ian