I have an issue using ‘Transform (Modify) Bone’ under the animation blueprint for a skeletal mesh. I only require rotation to reflect changes in a single variable. However, no matter what values are passed to the skeletal control no change occurs in the selected bone’s transform. This pic describes my setup:
The mesh is used as part of a ‘Wheeled vehicle’ character controller though I’m not certain that it’s causing any overwrite. Ive tested the following, which effected no change:
-Making sure the bone is not set as a wheel for the vehicle
-Changing the physics between ‘default’ and ‘kinematic’ or removing collision bodies entirely
-Importing a copy of the .FBX for a basic test and building a bare animation blueprint, not tied to a character blueprint
The solution to this post may suggest where the problem lies, however I have tested removing all physics from the bone. Unless the OP was referring to something else when he removed a ‘body instance’ from his setup.
The same issue has been encountered in the following post, however the workaround of triggering a prefab animation won’t solve my issue, as I need the transform to react to changing variables.
Currently using 4.7 preview 8 if it makes any difference.
Thanks anyone who has an input on this.
When you manipulate bone transforms involving Mesh Space Ref Pose Node, you should ensure that you unlock the rotation mode, because you want to override the “main” behavior of the engine. Did you define it to BMM Additive or BMM Replace like in the screenshot below? Check the doc for more details about Rotation Mode.
Click on Transform (Modify) Bone node → Details panel → Rotation → Rotation Mode and select something different than BMM Ignore…The Rotation space of course depends of your Pitch Rotation transform space, usually component space (relative) or world space (absolute).
In case someone else stumbles on this forum thread, there is another way to “multiply” a bone rotation, instead of just adding or replacing to it, using Apply a Percentage of Rotation
This can be frustrating, since searching for “rotate” or “multiply” or even “bone” does not cause it to show up in editor or on Google.
In the case of a vehicle or some other type of rigid body mesh, you’d be better off using static meshes with sockets and then parenting the meshes to each other. Then you’ve got easy rotational control without having to worry about modifying bones.
For example, I’m using this method for a gun turret. I added a socket to the base of the turret for where the Top goes, then I added a socket to the top for where the gun is located, then I added two sockets to the gun for where the barrels go. Then inside my BP I simply parent all the pieces together and position them at their respective sockets so everything is linked together in the same way it would be with a skeletal mesh, but I can simply rotate the meshes or the sockets to animate the pieces.
