In this very short video, I’ll talk about the Purge Unused Data tool available in Blender 4.2, which I believe will be particularly appreciated by those, like me, who have been using Blender for a long time.
Video Transcript
Hello everyone! In this very short video, I’ll talk about the Purge Unused Data tool available in Blender 4.2, which I believe will be particularly appreciated by those, like me, who have been using Blender for a long time. In older versions, this tool wasn’t available, and we had to use various methods to perform the operation it now handles.
Specifically, the tool allows you to quickly remove from the current project all the data and resources that are no longer in use, indicated by a 0 next to their names. I’ll immediately show you a case where this situation might occur.
I’ve imported a 3D model into my Blender project, but I plan to replace its Material with a different one.
If I click on the X symbol next to the material’s name while holding the SHIFT key, Blender sets the number of users of that resource to 0, in this case, the Material and all the Textures it uses.
However, in previous versions, it could happen that, even after saving the project, these resources would still be there when reopening the file. This could make the project confusing and, more importantly, cause the file to take up a lot of disk space, as the resources were retained within the project.
If the Pack Resources option from the File menu is selected, resources such as images used as Textures are also stored in the Blender file, which can take up a considerable amount of disk space.
Starting from this version of Blender, you can use the Purge Unused Data tool, available in the Clean Up submenu within the File menu.
The tool will provide a summary of the data that will be removed, with the option to also delete linked data and perform a recursive removal of unused data.
As you can see, in my case, Blender has found not only the Material but also the 3 images and the nodes associated with it.
After confirming the operation, the resources will no longer be available in the project, as you can verify by opening not only the list of Materials but also the Image Editor to check for the images used as Textures, which will no longer be listed.
Now we can save the project without the risk of storing unused data.
I’d like to remind you that if you need to store data in the file that, at the moment, isn’t being used by any object, you need to click on the shield icon next to the data.
An "F" will appear next to the resource’s name, indicating that this resource is assigned to a fake user, ensuring that it remains in the project file.
As I mentioned earlier, to remove a resource from all of its users, you need to hold down the SHIFT key while clicking on the X symbol next to the resource’s name.
I hope this short video was helpful! See you soon!