It's been going around for some time now that one must disable shadows on track props, and it has been picked up like some kind of mapper meme that gets repeated over and over to the point it is quite annoying, especially because it is incorrect. I'm tired of people spending more time on my alpha maps ranting about track shadows than giving me feedback, and that also goes for anyone else's maps during gameday. So I'm going to try and set things straight.
Why They're Ugly
Vrad determines shadows for props by their collision model. This works for most props, but quite a few don't have collision models, including the track props, the rock rubble, and plants. When a prop doesn't have a collision model, vrad defaults to using the prop's bounding box, which is just a rectangle drawn around the prop. Of course, this in no way matches the shape of the prop, so you end up with ugly shadows and pitch black ground.
How to Fix It
Vrad doesn't have to use the bounding box though. Parameters can be passed to it to use the model's actual mesh to create shadows. Naturally, this will lengthen your compile time, and should only be done for betas/release candidates.
Youme created a nice tutorial on how to fix ugly shadows here:
http://forums.tf2maps.net/showthread.php?t=2994
Why It Doesn't Matter in Alpha
So, as you can see, you can get nice, realistic shadows for your tracks and other props without collision models with a lengthy lighting compile. Of course, alphas and lengthy lighting compiles don't mix, so you won't be doing that. Which means track props will have ugly shadows in alphas. Unless you really want to select all your tracks, disable shadows, and when you get to beta, have to reselect them all and turn shadows back on, you can just leave them on.
And playtesters, deal with it. Alphas are not pretty. Track shadows don't disturb gameplay.
[Tip] Track Shadows (and why not to disable them)
