Changes to Bones and Constraints

Hello developers! A small spooky update for you:

Since we released Bones for rigs and skinned meshes last year, their functionality with simulated Constraints was limited. While you could use them as Attachments, any movement from animations would not update the Constraint.

This changes now!

Constraints attached to Bones will use the animated position of those Bones.

This has the potential to cause issues with games that may have been attaching constraints to rig bones, expecting them to not move with the animation. To fix this, you should add a separate Attachment to your mesh at the desired position

There’s some known issues and more work to do to bring Bones to feature parity with Attachments, including:

  • FIXED 11/18 The TransformedCFrame and WorldTransformedCFrame properties on the bone may be inaccurate when getting these values right after updating a parent bone’s Transform.
  • Correct constraint widget rendering (currently they may look off visually, you can notice this in the gif).
  • Effects (lights, particles, beams) attached to Bones need to update with animated positions.



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Would it be possible to attach parts via WeldConstraints to bones eventually? At the moment, Adopt Me is limited to using R15-imported rigs (where the parts are physically moved) because we can’t attach accessories to Custom-imported rigs (where only the bones move).


Yes, we are working on options to set up rigid constraints using Attachments and Bones.

Edit: It’s here: New Physics Class: RigidConstraint


As usual, the Roblox engineers are working wonders.

This update is fantastic for me as a developer who works with skinned mesh characters all the time.

Previously, rigging objects to the hand (or really anywhere) could either be done through some complex blender stuffs or using Bone.TransformedWorldCFrame afaik.

Yet another truly incredible update to help make skinned mesh much more fun to work with :slight_smile:


Are there any plans to allow bone selection and movement within the animation editor? Right now you have to click on the specific bone within the UI, instead of being able to just click on the bone within the viewport. This slows things down pretty significantly if I need to adjust animations within studio instead of Blender.


This is an awesome update and will make my, as well as others, workflow a lot easier.

Time to make some spooky scary skeletons.


Yes, finally! I have been waiting for this for months. At last I can continue my game, thank you!!


thank you thank you thank you thank you!! this should make it much easier to have accessories attached to the player ragdoll


This is going to be extremely helpful when attaching items to certain parts of a rigged character’s body. I had to scrap a small game idea I had because I couldn’t figure out a way to attach a tool to my rigged character’s hand, but this pretty much solves it completely!


This update was much needed! Finally it will make attachments more workable with bones. Any ETA on when we’ll be able to select bones from the viewport when animating them?


Will bones ever support animated scale? There’s a lot of applications of it that can’t be reasonably implemented with tweens.


Yesssss!!! I love this update! I’m working with mesh deformation almost everyday and sometimes gets a pain.


Great update! I bet loads more people seeked this for a long time.


Awesome, now we can have armor separate from the characters rather than having to separate character models with and without armor.

Now we just need to be able to rig bones to mesh parts in Studio instead of having to do it in a third-party program.

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Great work for changes accessories to bones and constraints i helpful to be attach a lot that will be able to completing update so you can known issues for attachments but that update with positions has custom would that using to bones for giving supported animation update and i did for works attached a tool can rigged character hand, but a lot things solves will that great update studio will giving developer at the time to changes for pretty much for continued solved completely to supported for using to accessories!


Yay! Thanks for this. I was putting off doing anything related to constraints because I heard they would eventually be fixed, just didn’t know when this would happen. In the meantime I just solved this with my own code, but you can guess the performance of that.
Well no more waiting for this I guess.

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Amaizing updates as usual very excited to try this out!

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So how exactly is this supposed to be set up? See the gif below…
I tried using a constraint parented to the bone, and the attachments parented to the wooden stake and the mesh (bc you can’t parent an attachment to the bone). The wooden stake still does not move with the animation. What am I missing?

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You treat the Bones just like they were Attachments. Set the Constarint’s Attachment properties to the Bone/Attachments you want. It does not matter where the Constraint is in the hierarchy.
(quick overview of Constraints and Attachments available here)