I want me trees models to be sprites when the camera is far away. I made a model with one face and called it tree_1.mdl. My problem is that this entity needs to be faced when in lod 1,2 and 3 and oriented when lod is 0. Is there and event when lod is changed or a property I can check in the action loop or do I have to check the distance to the camera?

If I remember right lod is depending on your clip_range (or camera.clip_far)
I think it was something like: 1/8 clip_range = lod1
1/4 = lod2
1/2 = lod3
You can change your Flags depending on the clip_range.
You have to take the distance between camera and model with vec_dist of course.

okay.. thanks