Motor6D stretching the planes of existence, opening the gates to oblivion, and crashing studio

Bug Reports Studio Bugs
#1

I’m not at all sure what happening here or exactly how to replicate it, but I welded a gun together using Motor6D and upon doing something, the gun stretches / distorts. http://i.imgur.com/Jyizsuc.jpg

I can kind of replicate it but I’m not exactly sure what’s going on to make it do this. I didn’t know this was even possible.

Edit: Video showing it: https://www.youtube.com/watch?v=yU-vPKSl0dk&feature=youtu.be

edit2: I realized that these lines are what are majorly contributing to the bug:

L1. local RA = game.Workspace.CurrentCamera.FPSModel.Right.AnimateBrick
L2. local newR = game.Workspace.CurrentCamera.FPSModel.Animations.Scoped.Right.f1.CFrame:inverse() * RA.CFrame * RA.AnimWeld.C0
L3. RA.AnimWeld.C0 = newR

#2

One of the offset cframes could be malformed

#3

How do I check for that?

#4

Okay it looks like matrix creep. Every time you update the offset, it loses a little precision, until it drifts into chaos. If the offsets are constant, try storing them instead of getting it each time.
(also beware of this when using model:SetPrimaryPartCFrame)

#5

Okay I’ll look into that. By the way, when the gun was done using Welds instead of Motor6D, there was no issue like this.

#6

Use Motor not Motor6D.

I don’t know if it will help but I know I’ve never had problems with Motors.

#7

I’m using Motor6D because it has better precision when needing to move complicated parts in stressed servers. Does Motor do the same?

#8

Motor doesn’t have the same move-parts-with-anchored-parts thing that Motor6D does. If you’re getting stretching, it means your CFrame math is wrong.

#9

The math works fine with normal welds. The error occurs when this happens:

L1. local RA = game.Workspace.CurrentCamera.FPSModel.Right.AnimateBrick
L2. local newR = game.Workspace.CurrentCamera.FPSModel.Animations.Scoped.Right.f1.CFrame:inverse() * RA.CFrame * RA.AnimWeld.C0
L3. RA.AnimWeld.C0 = newR