Mostly working Surf

[Zrocket]

I think I finally figured it out. Your choice to subtract toi from the Y velocity only at ground tick 1 was messing with later gravity calculations. From my testing, subtracting it every time doesn't seem to hamper bunny hopping acceleration, but let me know if there's a problem.

There are still some very minor details that make surfing here technically different to source engine surfing (e.g. holding forward doesn't pull you down), but I'd say it's pretty close.