Using custom inputs

By default, Motion Toolkit utilizes its own plugin content skeletal mesh, which is located in the Motion Toolkit plugin Content folder, across all tools. However, you can use any animation input of your choice and select any skeletal mesh for the animation output by leveraging our customized user interface alongside Unreal Engine's robust retargeting features.

IK Retargeting setup

To utilize custom inputs or request custom outputs from the plugin, you must associate your skeletal meshes with the necessary IK Retargeter assets to enable the retargeting process. In order to make a skeletal mesh compatible with an IK Retargeter you must create an IKRig asset.

Please consult the official documentation for the creation and setup of IK Rig

IK Rig in Unreal Engine | Unreal Engine 5.4 Documentation | Epic Developer CommunityEpic Games Developer

Input animation

Once the IK Rig is created, you must establish an IK Retargeter that uses the IK Rig of the custom input as the source rig and our plugin's content IK Rig, located at Plugins/Motion Toolkit Content/SMPL , as the target rig.

Output mesh

Once the IK Rig is created, you must establish an IK Retargeter that uses the IK Rig of the custom input as the target rig and our plugin's content IK Rig, located at Plugins/Motion Toolkit Content/SMPL , as the source rig.

Please consult the official documentation for the creation and setup of IK Retargeters

IK Rig Animation Retargeting in Unreal Engine | Unreal Engine 5.4 Documentation | Epic Developer CommunityEpic Games Developer

Input Animation Widget

When utilizing an animation as input with a skeletal mesh different from the default used by Motion Toolkit, it is necessary to create specific assets to retarget the animation accordingly.

In each tool (Motion Edit/Stitch) that employs animations as inputs, you will find the input animation widget:

You can assign an animation using the default skeletal mesh of our plugin, eliminating the need for retargeting:

If you assign an animation with a different skeletal mesh, an additional input will appear, prompting you to assign a retargeter asset.

When browsing the available retargeter assets, our plugin will automatically filter the assets in your Content folder, presenting only those suitable for retargeting an animation from your source skeletal mesh to the default skeletal mesh of our plugin. If you cannot locate the desired retargeter asset, please ensure that your IK rigs and retargeters are set up correctly. For further information, please refer to Input animation section.

Once you assign the retargeter asset, your input animation will be compatible with the plugin's input animation specifications.

Output Skeletal Mesh Widget

In the same context, all output animations from the various tools are based on the default skeletal mesh of our plugin. When you open a tool within the plugin, the default skeletal mesh is automatically selected.

If you wish to retarget your animations to a different skeletal mesh of your choice, simply select the desired skeletal mesh. An additional input will appear, prompting you to assign a retargeter asset.

When browsing the available retargeter assets, our plugin will automatically filter the assets in your Content folder, presenting only those suitable for retargeting an animation from default skeletal mesh of our plugin to yout source skeletal mesh. If you cannot locate the desired retargeter asset, please ensure that your IK rigs and retargeters are set up correctly. For further information, please refer to Output mesh section.

Once you assign the retargeter asset, your output mesh will be compatible with the plugin's output mesh specifications.