Vector.Rotate() ?

Garry's Mod coding
#1

Sorry, but is this function broken? I was using it earlier, but for some reason, it just entirely fails at what it seems to be intended to do.

I’ve been giving a vector an angle to rotate, but for some reason it gives an entirely unreasonable result. The following code seemed to work in one direction, but when rotated past -90 or +90 (to something like -135 or + 135) on the yaw angle, it just flat out broke. Started spitting out insane results. I’d give it a 30 degree angle to rotate around, and it would rotate by a miniscule amount. It would also jump around randomly, for no apparent reason. To sum this up in code…

This code is broken. I had assumed it would work just like the second piece of code.



VectorToBeRotated:Rotate(AngleDifference)

But it doesn’t seem to?



local InitialLength = VectorToBeRotated:Length()
local InitialAngle = VectorToBeRotated:Angle()
local FinalVector = ((InitialAngle + AngleDifference):Forward()) * InitialLength

So, my question is, is this just borked? If so, is there a better way of rotating the angle than what I’m using? Or rather, since I know there is, can someone point me to the math behind it?

#2

Perhaps you could use Angle.RotateAroundAxis() and then convert that to a vector instead?

#3

That’s essentially what I’m doing by just adding the angle and going Angle:Forward(). I’m not actually convinced that there is a better way of doing this, at this point. I’m just curious as to why Vector.Rotate screws up for me.

#4

Hey, resurrecting this thread to see if anyone has any idea. My way works fine, I’m just curious if vector.Rotate is actually broken.

#5

Maybe it’s just not doing what you expect it to? I could be wrong but I believe it rotates around the origin, so Vector(0,0,0).

#6

Vector:Rotate() doesn’t make much sense anyway because you don’t really know in which order it’s being rotated, and how exactly. You’d better convert your vector to an angle, perform Angle:RotateAroundAxis() on it, and then get the vector back using Angle:Forward(). This way you know exactly what you’re doing, and what the resulting vector will be.