I have sent the following to various persons interested in multi-button trackballs and/or low dexterity issues.
> > Hello, I am thinking of releasing an unofficial patch to the XFree86 > mouse driver renamed to trackball. I would like to get feedback as to > whether this would be useful. > > XFree86 is an implementation of X11, and is the most commonly used > windowing system for LINUX, BSD, freeBSD, and many flavors of UNIX. > > My unofficially patched mouse driver, renamed trackball, is identical > to the standard XFree86 mouse driver except that it implements Drag > Locking. > > Drag locking exploits the extra buttons on certain trackballs, to > simulate "locking" certain other buttons down. This allows a person to > separate the action of indicating in beginning/ending of a drag, from > the act of moving the ball that is, to move the mouse cursor. The > beginning and end of the "drag" is indicated by clicking on these > extra buttons. > > It is my understanding that low dexterity people often use trackballs > so that the act of clicking can be separated from the act of > positioning the mouse cursor. > > My unofficial patch, allows people to separate the acts of beginning > and ending of a drag from the act of moving the ball and hence the > mouse cursor. Thus, it is not necessary to hold down a button and move > the ball at the same time. > > The manufacturers of 4 button trackballs often provide drivers that > give "drag lock" functionality in the context of Microsoft > proprietary windowing systems. > > My question is would this be useful to low dexterity people? > There might be problems getting the unofficially patched driver > installed on many systems. These problems might be both technical > and bureaucratic. > > It is unlikely that XFree86 will support any kind of drag lock > functionality in the immediate future. > > Please feel free to forward this message to anyone in the low > dexterity community likely to have an opinion. > > The README file that I contemplate for this patch follows: > > 4 Button Trackball Support for XFree86: An Unofficial Patch > > Paul Elliott > > 14 November 2002 > > 1. Introduction > > This document describes an unofficial patch to the XFree86 mouse driver, > renamed trackball. The trackball driver works identically to the XFree86 > mouse driver except for the addition of drag lock support. Drag lock buttons > are extra buttons that are pressed (and released, i.e. clicked ) to indicate > the beginning of a "drag" for another button. This is convenient for every- > one, and may be necessary for low dexterity persons. > > The manufacturers of 4 button trackballs often provide drivers that give > "drag lock" functionality in the context of Big Company proprietary windowing > systems. > > This patch brings similar abilities to XFree86. > > 2. Supported Hardware and software Platforms > > I have tested this patch with: 4.2.0 (as patched by SuSE), Linux version > 2.4.16-4GB, and the Kensington expert Mouse (which is really a trackball). > > This patch should work with any 4 button trackball for which XFree86 recog- > nizes button clicks for the extra buttons. I can see no reason that this > software would not work on other platforms although I only have the above > platform for testing. > > 3. Configuring Your Trackball and XF86Config Options > > The trackball driver is configured identically to the mouse driver except > that the name of the driver is trackball and the additonal option DragLock- > Buttons. > > 3.1 Drag Lock Buttons > > Some people find it difficult or inconvenient to hold a trackball button > down, while at the same time moving the ball. Drag lock buttons simulate the > holding down of another button. When a drag lock button is first pressed, > its target buttons is "locked" down until the second time the lock button is > released, or until the button itself is pressed and released. This allows the > starting of a drag, the movement of the trackball, and the ending of the drag > to be separate operations. > > Option "DragLockButtons" "W X Y Z" > > This option consists of pairs of buttons. Each lock button number is followed > by the number of the button that it locks. In the above, button number "W" is > a drag lock button for button "X" and button number "Y" is a drag lock button > for button "Z". > > It may not be desirable to use multiple buttons as drag locks. Instead, a > "master drag lock button" may be defined. A master drag lock button acts as a > "META" key. After a master lock button is released, the next button pressed > is "locked" and not released until the second time the real button is > released. > > Option "DragLockButtons" "M" > > Since button "M" is unpaired it is a master drag lock button. > > 4. Configuration Examples > > The Kensington Expert mouse is really a trackball. It has 4 buttons arranged > in a rectangle around the ball. Button number 2 which most software inter- > prets as the "middle" mouse button is in the upper left conner of this track- > ball. > > Section "InputDevice" > Identifier "DLB" > Driver "trackball" > Option "Protocol" "ThinkingMousePS/2" > Option "Buttons" "3" > Option "Emulate3Buttons" > Option "Device" "/dev/mouse" > Option "DragLockButtons" "2 1 4 3" > EndSection > > In this example, button 2 is a drag lock button for button number 1, and but- > ton 4 is a drag lock button for button 3. Since button 2 is above button 1 > and button 4 is above button 3 in the layout of this trackball, this is rea- > sonable. > > Because button 2 is being used as a drag lock, it can not be used as an ordi- > nary button. However, it can be activated by using the "Emulate3Buttons" fea- > ture. However, some people may be unable to press two buttons at the same > time. They may prefer the following InputDevice section which defines button > 4 as a master drag lock button, and leaves button 2 free for ordinary use. > > Section "InputDevice" > Identifier "MasterDLB" > Driver "trackball" > Option "Protocol" "ThinkingMousePS/2" > Option "Buttons" "3" > Option "Device" "/dev/mouse" > Option "DragLockButtons" "4" > EndSection > > Generated from XFree86: >xc/programs/Xserver/hw/xfree86/doc/sgml/trackball.sgml,v 1.11 2002/11/14 00:25:23 >pelliott Exp $ > > Paul Elliott 1(512)837-1096 > [EMAIL PROTECTED] PMB 181, 11900 Metric Blvd Suite J > http://www.io.com/~pelliott/pme/ Austin TX 78758-3117 > -- Paul Elliott 1(512)837-1096 [EMAIL PROTECTED] PMB 181, 11900 Metric Blvd Suite J http://www.io.com/~pelliott/pme/ Austin TX 78758-3117 _______________________________________________ Xpert mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xpert
