Around lines 29-37 in the CarScript found in the Jeep found in the roblox suburban map, from my findings I’m pretty sure that the offset * car.chassis.CFrame = thruster.CFrame when the offset multiplied by the car.Chassis.CFrame equals thruster.CFrame:
So I’m pretty sure I’m good on line 29, however 30, I read the CFrame Math Operators Article on vectorToObjectSpace() but still do not understand how it works or rather the purpose of it.
line 30:
local speed = car.Chassis.CFrame:vectorToObjectSpace(car.Chassis.Velocity)
and I’m pretty sure I can understand the rest (31-37) once I understand this line. Can someone explain in depth? Thanks!
As for vectortoobjectspace, its basically the same as toobjectspace (or a:Inverse * b like you have above), but it only looks at the rotation, and that rotation is in the form of a vector
Say you have two cframes a and b
Here are two ways to get the relative rotation, one more similar to toobjectspace and the other more similar to vectortoobjectspace:
(a:Inverse() * b).LookVector --more similar to toobjectspace
((a-a.p):Inverse() * CFrame.new(Vector3.new(0,0,0), b.LookVector)).LookVector --more similar to vectortoobjectspace
The formal method uses a shortcut like (a-a.p):Inverse() * vector, but they should be the same
So from my understanding, vectorToObjectSpace takes a CFrames rotation Inverse() ignoring x, y, z and multiplies it by a vector. What does this do? Is it some kind of rotational offset?
It rotates the vector by the inverse (opposite) rotation of the cframe put as simply as I can
So it subtracts the rotation of the cframe from the rotation of the vector
Think of it like this, what can I multiply (x) by a to get b. That is just a linear equation of ax=b, solve for x which is b/a. As you may know, matrix division doesnt exist. What does exist though is matrix multiplication, also known as the hadamard product. If you don’t know, the inverse of a value depends on what operands you which to invert. Say I have 5 - 10 and want to make it so that I will get the same expression with just addition I would use the additive inverse to said negator (10) 5 + -10 = 5-10 and therefore applies to all sets, that means that b/a = b*1/a. :Inverse() in roblox is the inverse of the hadamard product
How does this apply to vectorToObjectSpace? My understanding of Inverse is that it can be used to cancel by multiplying a CFrame Inverse on both sides, leaving behind a new subject. Tbh I did not get a lot of what you said cause I don’t know the terminology that u used.
@PapaBreadd
Edit: I understand how formula works I just don’t know how the speed is worked out using vectorToObjectSpace, I thought speed was distance / time:
local speed = car.Chassis.CFrame:vectorToObjectSpace(car.Chassis.Velocity)
im pretty sure it just makes it relative to the cframes lookat vectors. like if the velocity was 0,0,1 it would be transformed to the cframes lookvector
Thank you, I completely forgot that multiplying a vector like Vector3.new(0, 0, -1) by a CFrame with the position part of the CFrame subtracted was the same as CFrame.LookVector. This clears up a lot of confusion for me
