Modders,
I've noticed folks going overboard on their bounds polygons. What I mean by this is: "using more coordinates than absolutely necessary to evoke a convincing level of hit-detection in-game."
The question you should now be asking is: "gee Trylobot, if you're so smart, what the heck should I be doing instead? I haven't noticed any problems."
Good question modders, I'm glad you asked. The problems you haven't noticed are insidious. They don't really affect anything at small scales. But when your ships are used en-masse, say in a mod compilation like U.'s Corvus or similar, these super-complex bounds polygons will slow down the computers belonging to the "economy / mid-range" level. In other words, not hardcore gaming machines like you and I are so fond of. And you
should be worried about this, because these folks are technically your audience. You're going to all this work, authoring this mod, ostensibly so that as many people as possible can play it. So you want to
Optimize.Best optimization: consider removing
literally every bounds coordinate you currently have and making a new one from scratch. If you want to look at perfection, load up some of the vanilla ships and look at their level of detail. Then think to yourself, "self, if the bounds polygon looks like this, and in-game I didn't notice anything funny, then isn't this enough?" The answer is yes. Yes it is. Use as
few bounds coordinates as possible to look right, and not a single one more. It's better for the game, better for performance, and better for the perceived quality of your mod.
EDIT: Here's an example from Ghoti:
This concludes a Public Service Announcement.
Update: April 19, 2013 - PRO TIP from Vinya
Use your image editor's "Pixelate" effect, and give a size of 5 (or higher). When setting up your ship's bounds, use this pixelated version of your ship. That way you won't be as inclined to include unnecessary details in the polygon.
Update: Addendum from Astro with illustrations