[Linuxwacom-discuss] Subpixel accuracy

[Radek <tru...@o2...>]

Hello,

I have some questions regarding the possibility of having subpixel
accuracy in drawing apps (like GIMP or so).

I'll try to describe the problem the best I can:
Lets say I run GIMP with an image viewed at 25% zoom, that is, one
pixel on display correnponds to 4x4 square on the image. Using the
tablet I draw a curve with a pencil tool (1x1 square brush without
antialiasing). I zoom image to 100% and see that the curve is not
smooth, but consists of short, straight sections either vertical,
horizontal or diagonal, like if it was snapped to 4x4 pixel grid.

I know that this is because GIMP gets the stylus coordinates with
accuracy limited to the resolution of my display. If there was a way to
make it receive (and properly interpret) stylus coordinates with an
increased precision (so that it would be limited by tablet's resolution
rather than display's), it would work as it should.

I've been googling to find a solution for this, but I've only found out
that it's a Xorg limitation and nothing can be done unless Xorg
supports it. Despite that, I think that there can be some workarounds.
One that came to my mind is to create some kind of virtual display with
a size in pixels close to the working area of tablet (so that the
drawing window of GIMP could be sent there), and put it on the
screen zoomed out. What do you think about it? Is it even possible?
I want to say here I'm not a linux guru nor a pro coder, so probably I
coudn't fix it myself.

But this issue is rather important for me, because it feels a little
pointless of having a tablet of a high resolution while not being able
to take any advantage of it.
Or maybe I'm just missing something?

Best regards,
Radek