Appending/linking the same object with the same metric size from Blender files with different unit scales in Blender 2.8 results in objects of different sizes. It seems, Blender respects only the internal Blender units when appending/linking an object and ignores the unit scale.

Is there a way to force Blender to respect unit scale when appending objects?

Steps to reproduce:

  1. Create a new scene and change the unit scale from 1 to 0.1 in the scene properties.
  2. Add a default cube with size 2m.
  3. Save the file and create a new scene.
  4. In the new scene leave the unit scale at the default setting of 1.
  5. Append the cube from the other file. The cube will now have a size of 20m. I would have expected it to have a size of 2m.
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    $\begingroup$ Hello :). Blender respects the scale of your target scene. In your example, Blender just multiplies the source scale (0,1) by 10 to match the target scale (1,0). To keep linked objects the same size, you need to keep uniform unit scale across linked files. $\endgroup$ – Jachym Michal Jan 6 at 19:38
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    $\begingroup$ That's what I suspected. But isn't this totally impractical? I can imagine scenarios in which I want to use assets which were created in another scale. Do I have to rescale such assets before every use? $\endgroup$ – Customizer Jan 6 at 20:19
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    $\begingroup$ Honestly, I can't think of a good reason to change the default unit scale of 1. I only change units km>meters>milimeters which doesn't affect linking/appending in any way. Would you mind sharing your reasons for changing the unit scale? :) $\endgroup$ – Jachym Michal Jan 6 at 20:37
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    $\begingroup$ Well, my answer was almost completely written, when your comment got me thinking again… For my current hard surface workflow changing the unit type will indeed probably be enough. It's just about better handling of small values in modifiers. Thanks for the indirect hint! ;) There is one other possible use case, untested by me though: Physics simulations seem often to have problems with small objects (at least that is my experience, but I don' really know what I'm doing, so…). I could imagine working with bigger blender units could be advantageous in these areas. $\endgroup$ – Customizer Jan 6 at 21:10
  • $\begingroup$ You're right about physics simulations, they often work better at larger sizes. But unit scale is ignored in simulations, so it's of no help there. Good luck with your project :). $\endgroup$ – Jachym Michal Jan 6 at 21:35

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