I would like to report a GUI scaling issue observed on Windows 11.
When using Studio One with the system display scaling set to 225%, the GUI of the Again Simple.VST3 plugin does not render correctly. The layout appears distorted, with incorrect vertical sizing.
Based on testing and behavior, it seems likely that the issue is related to VSTGUI not fully supporting non-integer scaling factors. In particular, fractional scaling such as 225% may not be handled properly, leading to incorrect view dimensions.
It would be helpful to clarify whether this is a known limitation of VSTGUI, and if there are recommended approaches or workarounds for supporting fractional DPI scaling on Windows.
Any guidance or confirmation would be appreciated.
A workaround I found was to override getSize() and implement it so that it calculates the size based on a fixed height and the scale factor.
All samples that implement their own UI appear to be problematic. getSize() is called repeatedly, but for some time after setScaleFactor() is invoked, it returns incorrect values; only the last two calls return the correct values. With this behavior, I suspect that Studio One cannot handle it correctly.
Do you have the latest Studio One version?
As far as I know, VSTGUI is behaving correctly. It handles resizing and scale factor changes according to the specs.
I just checked this in Reaper and Cubase and in both applications the VSTGUI based examples of the SDK render correctly. This points to Studio One doing something wrong.
