I've fixed a few things. I was having a weird problem where the tank actually floated 2meters above the ground. I changed the model's origin, and it started working correctly.

Also, I was being silly when I was frustrated to death earlier, and changed the tank to a sphere to... uh... kick it around and vent some anger, lol. And I noticed the tracks didn't stay mounted to the tank. So I added:

my.pan = panzer.pan;
my.x = panzer.x;
my.y = panzer.y;
my.tilt = panzer.tilt;
my.roll = panzer.roll;

...and now the tracks stay mounted to the tank no matter which way it goes, rolls, turns, etc. I've also modified the tank model by adding some invisible, unconnected vertices at each corner, where I want the collision hull be. Then I used vec_for_vertex to get the position of each one, and use set_min/max to create a properly scaled bounding box. I guess I'm not quite as stupid as I appear! LOL!


However, the method you mentioned for animating skins is problematic for me. It's done this way in the dozer demo everyone suggested. When I try to compile his source code, it crashes, due to the dozer's track action, right at the line where the u and v values are shifted. For some reason, my engine doesn't like those instructions. Plus, I can't find any examples of how to do things like this that actually work. The manuals are pretty vague on such topics...