Tablet pointer offset malfunction with scale ratio + multi-monitor
Update on 2020-12-07 by Jehan
So far the reproduction for this issue seems to be:
- Have a setup with several monitors
- Have a non-×1 scale ratio on one monitor
- Both 2.10.22 and 2.99.2 (so not fixed in GTK+3)
- Windows only?
- Tablet only?
Update on 2021-04-27 by Jehan
It seems that gtk!3275 should fix the issue. So now we have to wait for it to be merged.
GIMP version: 2.10.20
This "bug" has been persistent since the initial date of installation --- Tablet is brand new & directly from the manufacturer (Huion)
RIG: MSI GF65 Thin
Package: Downloaded from site "https://www.gimp.org/downloads/"
The digital pen specifically designed (that came within the original tablet "box") --- as well as the additional "gift" pen [both] have an offset issue that changes in severity according to the pen's position on the canvas*; an issue that's present ONLY in Gimp but not programs such as PaintDotNet, Photoshop, or Blender. Also, tests in "Snip" -- the Windows "tool" --- yield results that I'd call nothing less than "perfect".
We've made several attempts to tweak the tablet/pen settings in both Gimp's preferences as well as directly in the Huion.exe. All pressure sensitivity tests were normal/flawless. In Gimp, however, pressure sensitivity DOES work as expected --- beautifully even. The offset alone has proven to be our Gimp-Kryptonite. Luckily, we can use the tablet in every way possible; so long as we have Dynamics --- mainly Pressure Opacity --- toggled off.
Attached "clip" showing changes in offset as the pen is moved from one side of the screen to the other as well as "extra" pressure sensitivity use shown.
Reproduction: Reproducible? [Always]
Toggled on "Dynamics"
Offset is most "off" when toggling on Pressure Opacity
Turning "Dynamics" back to "off" stops the bug in its tracks
3.2. Opening PaintDotNet (while Gimp is running, the Dynamics enabled & bug present) still yields satisfactory results in PaintDotNet ONLY …
Expected result: We [honestly] expected the pen/offset to work as it does in any of the other programs it's used in... where the "brush" is directly beneath the pen nib.
Actual result: the brush is visible/paints at least 3 cm. away from the nib's point of contact on the tablet.
There have been no problems with Gimp crashing, warnings, or error reports (etc) as a result of this particular bug.