Re: [Linuxwacom-discuss] Intuos4 and pointer jitter

[SHIRAKAWA A. <shi...@gm...>]

Ping wrote:
> If it works all right on Windows, it is not a hardware issue.  Email me 
> your Xorg.0.log and xorg.conf (if you have one, if not the output of 
> "xinput list").  I hope it is not a driver issue either :).

Today I tried installing 0.8.5-1 Linux drivers on my Ubuntu machine, but 
they didn't solve my problem. If it helps, I found out that this jitter 
becomes VERY evident (the pointer becomes very shaky, impossible to not 
notice it) when mapping the screen area to a very small area of the 
tablet (for example 1x1 inches). I propose this as a test for other 
Intuos4 users. Please set the mapping to a very small portion of the 
tablet and see what happens.

By using a very small portion of the tablet I noticed also that 
increasing the suppress value while mitigates this problem makes the 
pointer move not very precisely, like if it was on a grid. On Windows 
even if i select a very small area of the tablet the pointer moves very 
smoothly with great precision, without shaking of course.

So Windows drivers:
- Don't appear to use a high suppress value, if at all
- Must set smoothness to a low value, as there is no perceived lag

I've read on the official Wacom forums that Intuos4 pens are 
individually calibrated. I wonder if tablets too have some sort of 
individual calibration and pass this information to Windows drivers in 
order to provide smooth operation.

This problem I'm having (on two different PCs with different CPU/chipset 
in the same place, but ONLY under Linux) must be either caused by 
something missing in Linuxwacom drivers or in some other subsystem 
(Xorg/Gnome/etc).

Yesterday I tried a 32 bit version of Ubuntu and I had the same problem. 
In the following days I'll try different Linux distributions and desktop 
managers and check what happens.

-- 
SHIRAKAWA Akira