Sketches on Linux don't take UI scaling into account

[processing-bot]

Created by: benfry

The sizing for most of the PDE works properly as of Processing 3.3, however sketches don't re-size based on the scaling.

There's an issue open here that covers the cross-platform aspects of making this work. The Windows version of this bug is here.

This issue is only for the Linux-specific parts of the problem, i.e. how are we gonna get the current UI scaling or DPI setting from the hodgepodge of window managers used with Linux.

[processing-bot]

Created by: gohai

I believe this information is supposed to be provided by xdpyinfo, which is part of the X server package. Not sure if this will work in all circumstances (window managers doing their thing regardless of X), but this would be the easiest/nicest solution if it did.

[processing-bot]

Created by: benfry

Thanks, good to know.

[processing-bot]

Created by: gohai

This should run xrdb -query, which returns e.g.

Xft.dpi:	192
Xft.antialias:	1
Xft.hinting:	1
Xft.hintstyle:	hintslight
Xft.rgba:	none
Xcursor.size:	48
Xcursor.theme:	Adwaita

The desktop manager is this Xft.dpi setting here, according to some heuristics and X server settings.

[processing-bot]

Created by: benfry

(Moving to the 4.0 repository and hiding off-topic comment about the PDE… this issue is specifically about sketches)

With 4.0 beta 6, sketch sizing should be in place for macOS (been there for a while) and Windows (arriving in beta 6). Linux is the last holdout; just needs more work/time/testing.