I’ve developed a plugin for Roblox that can export any Roblox rig into Blender and generate a Blender Armature (rig) equivalent to the Roblox one using the accompanying Blender addon. Then, in Blender an animation can be designed. When done, the Blender addon can be used to generate Roblox animation data equivalent to the animation designed in Blender. Using the Roblox plugin, this can be imported back into Roblox again.
Note: Skinned meshes/bones are not supported. If you want to animate a skinned mesh you probably want to use the built-in .fbx animation importer instead.
Experiencing issues? Check the “Common issues” section in this post for solutions to common problems!
Installing
Use this Roblox plugin: Blender rig exporter/animation importer - Roblox
Use this Blender addon (save as “something.py”):
Blender 2.80, 2.82, 2.91, 2.93+: https://pastebin.com/raw/V5aBemWL
Blender 2.79: No longer maintained.
Modified addon code from @XAXA which auto-adds various constraints for R15 rigs to limit rotations of some joints and properties to selectively disable transformations of certain bones on export: Blender rig exporter/animation importer - #214 by XAXA (Mostly useful to adjust imported animations and blocky rigs, see the post for details…) (note: now very slightly outdated, but still compatible as long as you use the older Blender 2.79)
Old Blender addon version
2.80+: https://pastebin.com/raw/Ehh9epGZ
2.79: https://pastebin.com/raw/B3cTejNi
(Blender 2.80 beta version)
https://pastebin.com/raw/TwaP10Vx
(Also current version)
https://hastebin.com/raw/xomulazalu
(Older version)
https://gist.githubusercontent.com/anonymous/53c9a149b35e5f2910276cf4657fd4e1/raw/aa4aaae4c0c15e6c69cb8b738dd3a41fb1c1a423/rbxblender.py
(Prehistoric version)
https://gist.githubusercontent.com/anonymous/7740bb5685cc60632563cb3536fe5ddd/raw/728194dfd4dd4b5dc3d3b6d46b769c31dbf1d60a/rbxblender.py
(Pre-earth version) https://gist.githubusercontent.com/anonymous/08965641f2fe3825c480eb7faacf9fb6/raw/429fed6ff0670e2612feca8e9d537c1b9dfe4b62/rbxblender.py
Blender 2.80: Install Blender addon though Edit → Preferences → Add-ons → Install from file → (select that one)
Blender 2.79: Install Blender addon though File → User preferences → Add-ons → Install from file → (select that one)
Example use cases
- Using a more sophisticated animation editor than Roblox Animation Editor plugin. You can use all constraints in Blender to help designing animation, most notably the inverse kinematics constraints.
- Record physics simulations in Blender to an animation which can then be played in a reliable way in Roblox.
- Motion capture animations.
- Import animations from external sources into Blender, then import back into Roblox.
Cool Mixamo animation I’ve stolen from @Santa_Root 
https://i.gyazo.com/aee78132723103855e33b6d9e3e2389c.mp4
Common issues
If you experience issues while importing, check the following things first:
-
Make sure you’re using the most recent plugin and addon versions. Incompatible versions can lead to various errors! Check the top of this post for the latest versions. If you’re getting an error containing
object.name = partnames[-index]in Blender you’re definitely using an outdated addon version! - Ensure no warnings are shown in the importer/exporter plugin when clicking the rig in Roblox.
- Ensure the rig loads properly when using the default Roblox animation editor. The importer/exporter Roblox plugin barely does any error checking, but the Roblox animation editor can provide helpful error messages indicating issues with your rig.
- Humanoid appearances (like clothing) do not get imported automatically anymore to work around Roblox changes interfering with this plugin. This is does not affect animation imports. Want those Humanoid-specific things to be visible anyway? You can manually export an obj of the character from Studio and import that into Blender (using the regular .obj importer), then manually link each imported mesh to the bones generated originally by this plugin.
- Rig Motor6Ds are expected to be a direct child of the parent part in the rig tree (typically a direct child of Part0). Other locations may cause the plugin to not find the joint. For regular R6/R15 rigs this is the case by default, usually.
Very basic how-to-use guide for Blender 2.80
- In Roblox, enable the plugin, click a Rig
- If successful, the GUI will appear
- Click “Export rig”, save the .obj file somewhere
- In Blender, go to File → Import → Import the .obj file.
- In Blender, in the right panel in the 3D view (press N if invisible), open the Rbx Animations tab, then click Rebuild rig. (Bones should be generated after clicking this button.)
- Select the created Armature, enter Pose mode (Tab → Pose mode).
- Move/rotate a bone, then create a keyframe (Make sure to select the LocRot keying set) (Or enable auto keying):
- Create another keyframe at another timestamp.
- Click Export animation in the right panel. This copies text to the system clipboard.
- In Roblox, click “Load large animation”, paste the text copied to the system clipboard. The animation will now be loaded in Roblox.
- Click “Upload animation” to upload it to Roblox as a Roblox animation.
Very basic how-to-use guide for Blender 2.79
Very basic how-to-use guide for Blender 2.79
- In Roblox, enable the plugin, click a Rig
- If successful, the GUI will appear
- Click “Export rig”, save the .obj file somewhere
- In Blender, on the left panel in the 3D view (press T if invisible), open the Animation tab, under Rbx Animations, select Import model. Import the .obj file.
- Click Rebuild rig in the left panel. (Bones should be visible now)
- Select the created Armature, enter Pose mode.
- Move/rotate a bone, then create a keyframe (Make sure to select the LocRot keying set) (Or enable auto keying):
- Create another keyframe at another timestamp.
- Click Export animation in the left panel. This copies text to the system clipboard.
- In Roblox, click “Load large animation”, paste the text copied to the system clipboard. The animation will now be loaded in Roblox.
- Click “Upload animation” to upload it to Roblox as a Roblox animation.
Video tutorial of the above steps (Blender 2.97): Roblox | Blender rig exporter/animation importer | Tutorial - YouTube (by @Santa_Root)
Importing FBX animation data into the generated armature
(Thanks to @Santa_Root for the awesome idea to use Mixamo animations!)
Just use the “Import FBX” button. The FBX file should contain one rig/armature with animation data. That animation data is then loaded and mapped to the generated armature. Technique used to convert is the same as described in the next section, but animation length is automatically derived too during import.
See also Blender rig exporter/animation importer - #30 by Den_S
Mapping arbitrary armatures to the generated armature (__Rig)
Mapping arbitrary armatures to the generated armature (`__Rig`) (Advanced)
If you export the Blender armature to another tool to animate using something other than Blender, then later import the armature back again (for example, Mixamo animations), you cannot just replace the original __Rig armature. This armature contains some important metadata.
The utility script below can map bones from one armature (called __Rig2) to the __Rig armature (based on bone names). This mapping is done in armature space. This script will also convert transformations done on the HumanoidRootPart to all childs of the HumanoidRootPart (In Roblox, the HRP should be stationary). It is assumed that all bones existing in __Rig also exist in __Rig2.
Before running the script, go to __Rig its Pose mode and select all the bones you want to create keyframes for (typically all).
Just use the “map keyframes by bone name” button within Blender. It will map the selected armature onto the generated armature by bone name. You have to set the frame range properly first though, as only frames during the set frame range will be mapped!
Generate IK constraints
In the left panel, click “Create IK constraints” to quickly generate IK constraints. In Pose mode, first select one or more bones at the end of the IK chain (e.g. feet, hands), then use the tool to generate the constraints. You can optionally generate pose bones too (recommended for long chains). You probably need to tune some constraint parameters after generating one, though…
Parameters
The scene frame start and end times determine how long the animation is in frames. The frames per second value determines how long each frame is during the conversion. The frame step parameter can be increased to reduce the sampling rate. For high quality animations, use a step rate of 1 at 30 fps. Increasing the value to a value between 2 and 5 results in smoother animations, typically (but it varies depending on the type of animation you create).
Sample rig
If you just want to try it out, you can use this place file containing a single R15 rig: RigSample.rbxl (20.3 KB)
Enjoy .
