Scaling a part in X scales it in Z after rotating (version 1.9)

[emberprototypes]

Bambu Studio Version

1.9

Where is the application from?

Bambu Lab Official website

OS version

Windows 10

Additional system information

No response

Printer

X1C

How to reproduce

See my Twitter post here: https://x.com/emberprototypes/status/1797859883183640670

• Import a part into Bambu studio
• Rotate it by laying a different face flat
• Unclick "uniform scaling" and try to scale in X and Y
• Version 1.9 will scale incorrectly

If you revert to 1.8.4 it scales as expected. I believe all previous versions worked this way. This is important because I scale parts manually to accommodate for XY shrinkage for materials like ABS and PC. See this issue for the need for shrinkage compensation: https://github.com/bambulab/BambuStudio/issues/2769

Actual results

Part is scaled incorrectly.

Expected results

Part should global scale in X and Y appropriately.

Project file & Debug log uploads

N/A - should work with any STL.

Checklist of files to include

• [X] Log file
• [X] Project file

[Haidiye00]

Hello, our scaling tool defaults to using the local coordinate system, which is the xyz direction of the local coordinate system. We will launch a scaling tool for the world coordinate system later, please stay tuned.

[emberprototypes]

This is not how it worked in previous versions though - if you try it on 1.8.4 and below, scaling values always applied to the world coordinate system, not the local coordinate system of the part.

[Haidiye00]

It used to be wrong

[emberprototypes]

I see. Was this in the release notes? This caused issues on my end because I was using the scaling function to compensate for shrinkage and because its behavior suddenly changed, I encountered lots of parts out of tolerance.

Please add a global scaling function in the future (or more importantly...implement the filament type shrinkage compensation).