Version 1.20 update

Pete Miller spent his bank holiday weekend revamping Mouzer. Version 1.20 includes new features and better management of its relationship with the WIMP. If you've previously read the main article go here for the update . Otherwise read on...

Version 1.10 update

The 1.10 version of Mouzer arose in response to a request from Chris Newman. Several days ago Chris wrote; "Mouzer - what fun! A small plea; Is there a way of removing Mouzer's icon from the icon bar ? Then, I could use it permanently without it taking up icon bar space."
This was an interesting programming challenge. It would involve setting up a 'hot key' that once pressed would remove Mouzer's icon from the bar. Pressing the hot key again would return the icon to the bar. With help from Martin Wuerthner  and Steve Fryatt, I've managed to satisfy Chris' request.

What does Mouzer do ?

Mouzer modifies the behaviour of the desktop mouse. Moving it off screen to the right causes it to reappear on the left, and vice versa. Similarly, moving off the top brings it back on the bottom, and vice versa. This effectively means that, from the point of view of the mouse, it is moving around the surface of a torus , rather than a rectangle. So the distance between any two points on the screen is, on average, less. Thus the typical mouse moving distance is less.


If your computer is configured to allow windows off screen, then if the mouse crosses an edge when dragging a window, the window jumps with the mouse.

To configure your computer correctly for Mouzer, click <menu> over the Task Manager icon, bottom right on the icon bar,  and select 'Configure'. Of the choices offered select 'Windows' and tick the boxes, as shown above.


Download the application from the link at the foot of this page, unzip it, and launch it in the standard RISC OS way. You will immediately notice that the mouse pointer is orange rather than the standard blue. This is to show that the screen wrapping feature is active. Try moving the pointer off screen. Try using the mouse to drag a window off screen. On the icon bar menu, Mouzer's behaviour can be toggled off and on by clicking on the 'Wrapping' menu item. When not active the pointer is returned to its usual blue colour.

Hot Key

By default, pressing <Shift>+<Ctrl>+"9" is intended to remove Mouzer's icon from the bar. I thought this was a good key combination because cats are rumoured to have nine lives. Try it without any other applications running and see if it works.
The problem with trying to set up a hot key is that many programs try to claim the obvious choices. Some choices are also accepted as standard. It would be unwise to use <Ctrl>+"C", for example, as many progrms use this to copy the selected text to the clipboard. As there is only a limited number of keys on a keyboard, it's probably impossible to find a choice that is certain to work.
If Mouzer does not respond to the default hot key it is because another application has intercepted it first, and told the WIMP the key press has been dealt with. In such a case, the WIMP stops offering the key press around the active programs and so Mouzer does not get offered a chance to respond to it. The WIMP first offers any key press to the program with the input focus. However, it would be convenient if Mouzer responded even when another program had the focus. So, Mouser has a 'Hot key hunter' option to search around for another key combination that does not get intercepted by the programs you commonly use.

User selected 'Hot Key'

Click on 'Key code' on Mouzer's menu. The 'Hot key hunter' window will open. Click over 'Place caret here'. Try pressing various key combinations. The first step is to find one that does not alter the text in the writable icon. When one is found, Mouzer will tell you and report the code. Do not press 'Set as hot key' yet. Instead, give the input focus to the program that intercepted the default hot key. Do this by clicking on it. Now try pressing the promising new hot key again. Does Mouzer again see and report it as a suitable candidate ? If it does, press 'Set as hot key'. If not, search again by trying further key combintions. To close the 'Hot key hunter' window select 'Key code' again on Mouzer's icon bar menu. Mouzer remembers the hot key selected by a user even if the system is shut down.

Job done

I enjoyed finding out about hot keys and learning how to use them in this short program. As a topic it forces the user to think a little bit more about what the WIMP is doing in order to power along the desktop. Incidentally, the office cat is called Mouzer. He frequently leaves by a first floor window only to immediately reappear at the office door. Spooky !
Thanks are due to Gavin Wraith , who provided feedback on the version 1.00 of Mouzer. 

The Pete Miller Upgrade (6th May 2011)

Pete Miller has improved the operation of Mouzer so that it works more efficiently, especially with Virtual Acorn. Excessive null event usage made his PC sound like a hoover; Hoovering now minimized! In addition to his work on the core of Mouzer he has added new features;
* With Mouzer's icon on the bar, click select on the icon to toggle wrapping on and off.
* When wrapping is active, press <SHIFT> when the pointer is over the icon bar area, which may be hidden under several other windows. This temporarily suspends wrapping. Trying to drag the pointer off the bottom of the screen causes the icon bar to jump to the foreground, in the standard RISC OS manner. Press <CTRL> to resume wrapping, or simply move the pointer upwards out of the icon bar.
* <CTRL>+"-" attempts to toggle between wrapping on and off. However, testing here has found that WebWonder, for example, intercepts this if it has the input focus. A solution is to give Mouzer the input focus in it's Hot Key Hunter window. This will force <CTRL>+"-" to toggle wrapping. I guess we could make that key user configurable too, but that would be another upgrade...
Many thanks to Pete Miller for the improvements and agreeing that his program code could be released. I had not intended to feature Mouzer quite so much in RISCOScode, but given the enthusiastic responce it has generated I thought it best to go with the flow.


Click on the image directly above to download Mouzer v1.20


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