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Physically Accurate Airboat Collision Model

Quite possibly the second worst idea I've ever had (first being a physically accurate buggy model, that worked out horribly)

The original collision model of the airboat was designed with a balance of practicality and performance in mind. Well, it's not 2004 anymore (and Garry's Mod isn't available for the original Xbox thankfully), so limitations be dammed, here's the airboat from Half-Life 2 where every bit of geometry fully collides as you would visually expect.

On a slightly more serious note, this is actually quite impractical, as the airboat no longer has a flat central pivot point at the bottom, and can now get stuck while going off the edge of ramps and such, not to mention that hitting stuff like the destructible poles you see in Half-Life 2 now causes the airboat to let you take damage and slows down more, since you're making contact much closer to the boat's center of gravity.

TL;DR: this is extremely dumb, but hey, you can carry stuff in the undercarriage now!

In theory, this should work perfectly fine with addons that change the materials/textures of the airboat. Hell, as long as an addon doesn't replace airboat.phy, it should technically work with this (all this addon does is override the default GMod airboat.phy)