This Blender addon allows you to import and export meshes and animations to and from the [PSK and PSA file formats](https://wiki.beyondunreal.com/PSK_%26_PSA_file_formats) used in many versions of the Unreal Engine.
* PSA sequences can be exported directly from actions or delineated using a scene's [timeline markers](https://docs.blender.org/manual/en/latest/animation/markers.html), pose markers, or NLA track strips, allowing direct use of the [NLA](https://docs.blender.org/manual/en/latest/editors/nla/index.html) when creating sequences.
For Blender 4.2 and higher, it is recommended to download the latest version from the [Blender Extensions](https://extensions.blender.org/add-ons/io-scene-psk-psa/) platform.
For Blender 4.1 and lower, you can install the addon manually by following these steps:
1. Download the .zip file of the latest compatible version for your Blender version (see [Legacy Compatibility](#legacy-compatibility)).
Below is a table of the latest addon versions that are compatible with older versions of Blender. These versions are no longer maintained and may contain bugs that have been fixed in newer versions. It is recommended to use the latest version of the addon for the best experience.
Critical bug fixes may be issued for legacy addon versions that are under [Blender's LTS maintenance period](https://www.blender.org/download/lts/). Once the LTS period has ended, legacy addon versions will no longer be supported by the maintainers of this repository, although the releases will still be available for download.
| Blender Version| Addon Version | Long Term Support |
> Note that in order to see the imported actions applied to your armature, you must use the [Dope Sheet](https://docs.blender.org/manual/en/latest/editors/dope_sheet/introduction.html) or [Nonlinear Animation](https://docs.blender.org/manual/en/latest/editors/nla/introduction.html) editors.
## Why can't I see the animations imported from my PSA?
Simply importing an animation into the scene will not automatically apply the action to the armature. This is in part because a PSA can have multiple sequences imported from it, and also that it's generally bad form for importers to modify the scene when they don't need to.
The PSA importer creates [Actions](https://docs.blender.org/manual/en/latest/animation/actions.html) for each of the selected sequences in the PSA. These actions can be applied to your armature via the [Action Editor](https://docs.blender.org/manual/en/latest/editors/dope_sheet/action.html) or [NLA Editor](https://docs.blender.org/manual/en/latest/editors/nla/index.html).
## Why are the mesh normals not accurate when importing a PSK extracted from [UE Viewer](https://www.gildor.org/en/projects/umodel)?
If preserving the mesh normals of models is important for your workflow, it is *not recommended* to export PSK files from UE Viewer. This is because UE Viewer makes no attempt to reconstruct the original [smoothing groups](https://en.wikipedia.org/wiki/Smoothing_group). As a result, the normals of imported PSK files will be incorrect when imported into Blender and will need to be manually fixed.
As a workaround, it is recommended to export [glTF](https://en.wikipedia.org/wiki/GlTF) meshes out of UE Viewer instead, since the glTF format has support for explicit normals and UE Viewer can correctly preserve the mesh normals on export. Note, however, that the imported glTF armature may have it's bones oriented incorrectly when imported into Blender. To mitigate this, you can combine the armature of PSK and the mesh of the glTF for best results.
There is also an open pull request to add support for exporting explicit normals from UE Viewer in the future: https://github.com/gildor2/UEViewer/pull/277.
