[Windcatcher]

Let me see if I can help.

To the best of my knowledge, the three-character race designation for the ships is "PRE" (race 72). Hell if I know why they chose that prefix, but I think that's what you're looking for.

Models don't have any collision-checking information, though some have bounding boxes as well as bounding sphere information. This is something that's common to all models, though. It's part of the 0x36 fragment specification.

Clients (not just EQ or MMORPG clients, but in general) handle collision avoidance with the world and everything in it. They way it's done is to define an ellipsoid around every player and mob, and check the ellipsoid against any objects that are in its BSP node or any nodes it intersects. This would include other mobs such as ships, but there's a catch: for most mob models (actual monsters), it's very expensive to check the player's ellipsoid against every polygon in the model, so it's better to check against something more simple, like a box around the mob model instead. Ships, since they are also mob models, would be an exception to this, and I wouldn't be surprised if there was a flag in the data somewhere that instructed the client to perform proper collision avoidance against it (on the other hand, though, from what I've learned about WLD files, I also wouldn't be surprised if the client simply had a hardcoded flag for any model wth race "PRE" -- the WLD format isn't all that great).

If you wanted to replace a non-animated model (like a ship), I'm not sure how you would do it with the live client. I suppose you could add the necessary fragments to a zone's <zone>_chr.s3d file and force-load it. It wouldn't be a trivial exercise, though. I've been wanting to add support to OZ to allow adding mob models to zones you create, but the problem has been a lack of source material. Adding non-animated models would probably be pretty easy. If we wanted to do animated models we would need to have a thorough discussion on available source material, especially formats, since WLD animated models require certain characteristics. Khan and I have been looking closely at the Quake 3 format but they don't have everything that WLD models require.