[arch-general] video display doesn't get refreshed in GIMP, it seems.

[phani]

i've got a strange problem: when zooming images in the GIMP (installed  
 from [extra]), viewing them  larger than the size they are being  
automatically zoomed to by default, they break up into unconnected,  
rectangular tiles.

moving (panning) them around with the mouse so that they partially leave  
the screen brings those parts back to be displayed properly. means i have  
to 'swivel' the image across all borders to get it to display properly.

in addition, applying scissors or path tool leaves artefacts on the image  
that can be removed the same way.

i've noticed this first with the development version of GIMP (2.9,  
compiled from GIT) and thought those were the new GIMP's growing pains --  
but then i noticed the same happening with the stable version (2.8).

i've tried switching to an earlier version of xf86-video-ati and to an  
earlier kernel, but neither rectifies the problem. i also tried different  
options in /etc/X11/xorg.conf.d/ 20-radeon.conf, whith the same result,  
i.e., none.

i've installed (stable) GIMP in (stable) openSUSE i'm keeping in a  
VirtualBox, and the problem doesn't happen there. i didn't find anything  
useful via google or the GIMP dev/users lists and am quite puzzled.  
wondering if one of you guys has an idea where to look?

seems to have something to do with the image being refreshed, or not being  
refreshed, but which part of the system is at fault baffles me.


i'm using arch +testing, and here are my system's details:

System: Host: laptop Kernel: 3.7.3-1-ARCH x86_64 (64 bit) Desktop: KDE  
4.9.98 Distro: Arch Linux
Machine: Mobo: ASUSTeK model: K53SK version: 1.0 serial:  
BSN12345678901234567
Bios: American Megatrends version: K53SK.203 date: 10/11/2011
CPU: Quad core Intel Core i7-2670QM CPU (HT-MCP) clocked at 800.00 MHz
Graphics: Card-1: Intel 2nd Generation Core Processor Family Integrated  
Graphics Controller
Card-2: Advanced Micro Devices [AMD] nee ATI Whistler LE [AMD Radeon HD  
6625M Graphics]
X.org: 1.13.1 drivers: ati,radeon,intel tty size: 114x37

-- 
phani.