While we currently have proj:SetAcceleration(accel), can this be abused to change the acceleration of just a single axis after its already in flight? The Wiki doesn't appear to show anything one way or the other.
Quick example:
local x = 0
local y = -1
local z = 0
proj:SetAcceleration(x,y,z)
Kykhu Oss https://youtu.be/JUgyGTgeZb8
Unit Thrower https://youtu.be/iV8YBXVxxeI
Beam Tentacle https://youtu.be/le5SNwHvC4c
Blackhole https://www.youtube.com/watch?v=D9NGQC5rr0c
Resurection https://www.youtube.com/watch?v=WdbIQ4vHkMs
That would probably be https://github.com/FAForever/fa/blob/develop/engine/Sim/Projectile.lua#L174 Get/SetVelocity.
Acceleration is used for the projectile to reach it's max speed
You can adjust this with Projectile:SetBallisticAcceleration(y). Gravity is -4.9 by default.
The documentation is a bit outdated, but you can also do SetBallisticAcceleration(x, y, z) for acceleration in any direction; I just tested it. Make sure your projectile's MaxSpeed is high enough for it to accelerate how you want it to.