Thanks Chris for that pointer! Applying the mentionned patch solves the pointer jerkiness issue when applying the "Coordinates Transformation Matrix" to my Atmel maXTouch touchscreen.
I attach the corrected patch which can be added to the current Quantal 'xserver-xorg-core' (1.13.0-0ubuntu6.1) source (in debian/patches and debian/patches/series) Cheers ** Patch added: "(for Quantal 12.10 'xserver-xorg-core' source)" https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1005321/+attachment/3499782/+files/238-dix-save-touchpoint-last-coordinates-before-transform.patch -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1005321 Title: Several pointing device related problems occur when a touchscreen is installed Status in “xorg-server” package in Ubuntu: Triaged Bug description: I'm running Kubuntu 12.04 64 bits on a Dell Inspiron One 2320, which has a touchscreen. Whenever the touchscreen is active, several weird problems related to the pointing device show up. Some examples: 1. In Libreoffice Calc, if I hover the mouse over the zoom control bar in the bottom right corner of Calc's window, the mouse grabs the zoom control by itself, without me clicking any button. If I move the mouse left and right, without ever touching its buttons, it drags the zoom control left and right. 2. In Libreoffice Calc, if I left-click a tab other than the currently selected one, the new tab is selected as expected, but the mouse behaves as if the clicked button had stuck. When I move the mouse after selecting another tab, the mouse cursor changes to the arrow with the little rectangle, as if it was dragging a cell. 3. In Chromium, if I right-click a link and left-click "Open link in new tab", the mouse behaves as if the left-click stuck. When I move the mouse after opening the new tab, the mouse cursor changes to the little hand grabbing a sheet, as if I was moving the clicked link. 4. In Chromium, if I middle-click a link to open it in a new tab and then left-click the newly opened tab, the mouse cursor changes to the cross with arrowed points (the move window cursor) and the window is restored, as if I had started to drag it and let it go right after. 5. In Handbrake, when a dialog opens, hovering the mouse over its text without pressing any button selects the text. Until now I haven't noticed similar problems with native KDE applications, except that in Kontact/KMail the mouse cursor image does not change according to the context (arrow cursor, text insertion cursor, etc.). Besides, there are several other problems related to the touchscreen itself: 1. I can drag objects around the screen using the touchscreen, but I can't click anywhere. When I tap the touchscreen to click, the mouse cursor goes under my finger, but as long as I stop touching the cursor goes to some random place of the screen and the click is not registered. 2. While I'm dragging objects using the touchscreen or while I'm drawing in Gimp or Kolourpaint using the touchscreen, the mouse cursor keeps jumping down and going back to where my finger is. For example, if I'm drawing an horizontal line with my finger, what I really get on the screen is almost a filled in rectangle, because as I slide the finger to one side, the mouse jumps down drawing a vertical line and then goes back to my finger and keeps doing that while I'm sliding my finger horizontally. I get several vertical lines very close to each other. If I'm dragging a window horizontally, it keeps jumping down and up again while I'm sliding the finger horizontally on the touchscreen. 3. Multitouch does not work After I got these results, I installed the following packages: utouch and its dependencies xinput-calibrator They made no difference at all. I then tried the following package: xserver-xorg-input-tslib After a reboot, this package disabled the touchscreen completely (?!) and that was how I found out that the problems with Libreoffice, Chromium, Handbrake and Kontact/KMail mentioned above were related to the touchscreen. All problems were gone, but no touchscreen either. Before I installed this package, xinput --list returned one device named "Quanta OpticalTouchScreen". After I installed the package, xinput --list shows two devices with exactly this name and the touchscreen stopped responding. Then I removed the previous package and installed this one: xserver-xorg-input-multitouch Which made no difference at all. The system returned to the previous state, i.e., the touchscreen is responding but all the above mentioned problems are back. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: xorg 1:7.6+12ubuntu1 ProcVersionSignature: Ubuntu 3.2.0-24.39-generic 3.2.16 Uname: Linux 3.2.0-24-generic x86_64 ApportVersion: 2.0.1-0ubuntu7 Architecture: amd64 Date: Sun May 27 20:25:09 2012 InstallationMedia: Kubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120423) ProcEnviron: LANGUAGE=pt_BR PATH=(custom, user) LANG=pt_BR.UTF-8 SHELL=/bin/bash SourcePackage: xorg UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1005321/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
