As a Roblox developer, it is currently too hard to derive information about what how a torque will affect a BasePart or Assembly. What I’m looking for is essentially the “Mass” and “AssemblyMass” properties of BasePart, but for angular mass instead of linear. This is vital information for rigid body physics that Roblox is lacking.
Example Issue
Let’s say you have scripted yourself a custom solution for vehicle aerodynamics, or vehicle tires, and you wanted to clamp the maximum acceleration of the solution to avoid numerical instability. How you would find the max force for this linearly:
MaxForce = AssemblyMass * MaxAcceleration
But for angular acceleration, there is no way to do this! You would have to go through every BasePart in the assembly, use some standard equations for rotational inertia, and then your end result may not match up with what the engine is using internally because it is a black box with no documentation for us!
What’s Frustrating
The engine has no data type for a 3x3 tensor, so this may be too hard/annoying to do. However BaseParts have two methods called “AngularAccelerationToTorque” and “TorqueToAngularAcceleration” that would perfectly fill this gap, but actually they are disabled for some unknown reason? If nothing else, I would love to see these methods enabled as theoretically they would fill the tensor gap assuming they would work for Assemblies, as well as including the effect of rotational dampening for our calculations.
If Roblox is able to address this issue, it would improve my development experience because I would not have to use rough estimations of rotational inertia that are incorrect.