Either way, this thing starts looking rather awesome.
How about tasks like hunting then? Or human-made obstacles or other birds? One of the game's objectives could be to woe another owl?
A few people have suggested challenges based on natural bird behavior, but I'm struggling to think of a way to turn them into compelling gameplay. Simulating stooping on rabbits, sparrows etc might be entertaining for ten minutes or so but if that was the main activity I'm pretty sure you'd get bored of it quickly. Thus the fantasy elements.
The trees on fire thing is actually intended as a check on the power of the fireball spell. It blows up shadow worms very nicely, but if you shoot downwards and miss you can take out a good chunk of the trees and structures you're supposed to be defending. Though I may include a high level enemy that can start forest fires; that would be a 'drop everything and intercept this now' challenge. The swan maiden character (that I am thinking of including) would have some sort of water spell to put them out again.
Since you´re mainly in the air other stuff in the air would make sense. Floating obstacles like hot air balloons and crap like that to make the air space more interesting.
I like the idea of balloons as 3D obstacles. I would like to make them magic energy collectors, then I can justify them being mirror-silver (opportunity for some cubic environment mapping) and tethered to the ground by long chains. Ideally there would be a particle effect of little points of light appearing on the sphere surface, sliding down to the base, then being conducted down the chain to some sort of storage artefact. Dogfighting in the middle of a field of those would be great, with all the particle reflections in the giant mirrored balloons. I'd probably have to dedicate a thread to updating the balloon environment maps though.
Does the game include things like thermals that you can use to gain lift without flapping, or is it just assuming fairly generic atmospheric conditions? It'd be cool if you could ride up high on thermals, or ride the wind up hill ridges or things like that.
Yes, but they won't really be relevant in combat scenarios. You'll be able to play with them in free flight mode, maybe I'll add some Pilotwings style challenges of 'travel across the map without flapping' that use them.
Is the procedural generation done by a library or your own code ?
My own code, except for an open source plug-in I'm using to do the tree trunk structure generation.