Is is possible for me to create a mesh at runtime, based on some random number seeds. Producing the data for the map should be easy enough, I just have no idea how I could turn this into a mesh.
do a web search for fractal terrain. There are quite a few demos of how to do this. I'm reasonably sure there are even some functions for producing a height map that could then be used irrlicht's terrain node
you can. Just open (or create) a blank IImage object, having the size that you want, and apply whatever terrain generation algorithm that you feel like using (I personally like perlin noise, mostly for its simplicity ).
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