Hi every one,
On my computer it seems that Blender (2.93 - Linux) records my pen strokes (on a drawing tablet) in screen resolution: if I draw a diagonal line (with Grease Pencil, active smooth/post-processing off), then zoom in, I can see the discrete vertical and horizontal “jumps” corresponding to my screen resolution (1). It’s frustrating since my tablet resolution is much higher than my screen’s one.
So I tried to find out if it was a known issue, a misconfiguration or maybe a misunderstanding… But I haven’t found anything yet. Or perhaps is it something with my computer/tablet, however I haven’t experienced such issues with other programs I use.
Then I digged a bit into the code with the silly idea that maybe Blender was using integer screen space cursor position to record pen strokes. So far, I found that GHOST_SystemX11 (2) has references to xinput axis_data, but only for pressure and tilt. It doesn’t seem to use axis_data and axis_data which would contain the pen position in tablet resolution (if I’m not mistaken).
So my (first) question is: does anyone know if Blender use x/y integers in screen resolution to record pen strokes (at least on Linux/X)? Thanks a lot.
(1) The size of the discrete jumps also depends on the Manhattan/Euclidean preference - but with 0px/0px for both, the size of the “jump” is 1px in screen space.
(2) blender/GHOST_SystemX11.cpp at ae085e301c2aac0d6956609bfe93a90a19f0e235 · blender/blender · GitHub