Electronics and Software
Engineering Innovation

XVI Extensions

X-Windows for the visually impaired

BEAM Ltd 1996

Release 2.4.2

This document is partitioned into the following sections:

Section 1
Introduction, outlines the contents of the XVI X-Terminal Software.
Section 2
User Guide; describes how to use XVI


Thank you for buying one of 's products. The XVI X-Terminal Software is an additional component to a BEAM BXTERM X-Terminal. Specifically developed to aid the use of a Bxterm by the partially sighted. XVI provides a number of additional features to a standard Bxterm.

Comprehensive Zoom Modes
XVI provides a number of additional zooming functions, the display can be `hot key' switched from resolutions of 175*140 to 1280*1024, in all resolutions a rapid hardware pan facility allows movement over the full 1280*1024.
Cursor Magnification
XVI provides the facility to zoom around current cursor position.
Cursor Colouring
The colour of the cursor may be modified to aid visibility.
Mouse free Control
Both the cursor and the panning of the display can be moved by keyboard keys.
Auto event tracking
XVI supports a range of optional tracking modes. These enable the automatic movement of the display area within a larger virtual area.

The Virtual Display

XVI uses a virtual display system. This system provides two areas, one, the visible area is that displayed upon the monitor, the other area is the virtual area within which the visible area moves. The following picture illustrates the general idea.

The view area moves within the larger virtual area automatically, either when the mouse nears the edge of the monitor screen or explicitly directed to move by use of an XVI `hot key' sequence.

XVI allows the size of the visible area to be zoomed. When zoomed every thing displayed within the visible area is larger but it displays less of the total virtual area.

The Magnifying Glass

During the normal use of windowing systems, the centre of attention is often the current cursor position, for example, to press an on-screen button the cursor may need to be over the button prior to pressing a mouse button. XVI has a facility to help with the tracking and locating of the cursor, it is called the magnifying glass. The magnifying glass constantly displays a greatly magnified image of the screen around the current cursor position. The effect is optional and may be switched on and off at will.

Cursor Colours

Generally the cursor under X-windows is black and white. XVI allow the colour of the cursor to be changed to enhance its visibility.


Tracking is a complex topic, its setup is dependent upon the application requirements of the user. Tracking is the means by which XVI can automatically moves the viewable area around within the hidden virtual area, automatically detecting the area of interest. Is is possible for XVI to track the following:
Attempt to track the current Motif data entry window. This option only works with Motif applications. The motif entry window is shown on the display as a 4 pixel wide black border around the input window, whenever this border moves XVI attempts to display it on the screen. Typically this tracking mode is most useful on data entry type applications.
Text Print
Tracks the last text printed on the display.
Text Cursor
Attempt to follow the current text cursor position.
Focus Window
Attempt to display the current focus window. The focus window is the window currently accepting keyboard and mouse input.
Drawing Commands
Attempt to follow drawing commands, these range from line drawing, to circle etc.
Stay in client
This mode differs from the above in that the tracking is programmed by the user to be a single client application. XVI will then constrain the visible area to windows generated by this client application.

Starting XVI

If you are using an XVI Bxterm then XVI may be automatically started up every time the machine is switched on. The controls for XVI at startup can be found in the "Startup Config" menu of the Bxterm xchoose application.

On Unix systems supporting the BEAM XVI server extensions XVI can be started in the normal X application manner.

The XVI primary dialog

The XVI main dialog, is a window area on the display,it comprises a number of distinct groups, each group is contained within a border and has a title. The zoom group has a title and two arrow buttons one pointing up the other down. The Pan Control group has a push button and a slider while the Tracking group comprises solely toggle buttons. To activate any button move the cursor over the item and press the left mouse button. The slider may be moved by pressing and holding the left mouse button while over the slider button, drag the button to the desired position and then release the mouse button.

The groups perform the following operations:


Up Arrow Icon
The zoom up button causes the entire screen to be magnified, once the monitor has had time to settle every thing will be displayed larger. It will be noted however, that not as much will be displayed. To view the portions forced off the display move the mouse toward the appropriate edge of the display and the entire screen will pan and make things visible.
There is a maximum level of zoom at which point further pressing of the button will have no effect.
Down Arrow Icon
The zoom down button has the reverse effect to the zoom up button described above
This indicates the current level of zoom.

Pan Control

When the zoom level is greater than one, all of the information is no longer displayed, a hidden area is created. The means by which this area is brought visible on the monitor screen is called panning. Normally this works using the cursor. Moving the cursor near the edge of the screen causes some of the hidden area to be displayed.
Keys Pan Display
This button controls the manner in which the keyboard cursor keys are interpreted by XVI. The text on the button indicates what the button will do, pressing the button when "Keys Pan Display" is displayed will cause the XVI cursor keys to pan the entire display. The alternative "Key Move Cursor" title allows the cursor to be moved by the keyboard.
The border slider adjusts the point at which the display automatically pans. This border can be used to keep the cursor within a small area on the monitor. This minimizes the distance from the centre of the screen that the cursor moves allowing the user to focus over a small area. ie Rather than the cursor moving around the screen the screen moves around the cursor and the focus point on the screen is fixed. The larger the border value the less distance the cursor moves from the centre of the display before the display pans.

Client Name

One of the Tracking modes of XVI ( more later ) allows the selection of a single application. The name of this application is indicated on the status line in this group. If no application is selected then the word "none" is displayed.

Other Items

User Preferences
This button allow the default settings for XVI to be changed. Various options can be changed, including the cursor colour.
The Help button pops up the on-line help facility.

Magnifying Glass

The Magnifying glass button switches on and off a magnifying glass window. This window will show in greatly magnified form, the region around the current cursor position. The level of zoom within this window can be increased and decreased my pressing the keyboard keys. The figure below is screen shot to the magnifier in use.
Mag Glass On/Off
This button turn the magnifying glass window on and off. It may also be controlled directly from the keyboard.
Mag Glass Stick
It is possible to stick the mag glass window to a fixed position on the screen. When stuck the magnifying glass does not pan like other windows but remains static.


XVI provides a number of optional modes of Tracking events that happen on the display. For example you may be viewing a small section of the display, elect to press some button, this causes a pop up dialog else where on the display that is not within the portion you can currently see. There are now two alternatives, the first is to use the mouse to pan around the display to find the pop up the second utilises the power of XVI to automatically move the viewing area around the pop up.

The Tracking options are selected from the main XVI dialog or by the use of the function keys F1 to F7, a function key must be pressed at the same time as the CTRL and SHIFT keys.

Most of the Tracking modes may be used together, for example it is possible to Track drawing commands and the text cursor, however due to the complex nature of many applications such modes may lead to unexpected results. The visual area may move to unexpected areas within the hidden virtual area. Be prepared to experiment and note that different applications may well require differing setups.

The Automatic Button
This button switches the automatic tracking of events on and off. In its automatic mode XVI attempts to follow all events. When off XVI still keeps track of the events but the visual area is not automatically moved.
TIP: If you want XVI to attempt to find the latest event then turn on and then off the automatic mode.
Motif is type of user interface, it is used by programmers to create many popular applications. XVI supports a mode of tracking specifically to aid the use of these applications. In Motif the current area of input, is high-lighted by a bounding rectangle, generally black. The Motif tacking mode attempts to track this rectangle keeping it within the visible area of the display. Typically this is useful for data entry applications.
Text Print
Text print tracking, attempts to follow the last character typed. Typical application is a word processor or simple text editor.
Text Cursor
Attempts to follow the text cursor.
Focus window
In X-Window applications, any window may at some time have associated with it what is called the focus. It is to this window that all keyboard and mouse input occurs. XVI can attempt to track this focus window.
Drawing Commands
Drawing commands include line drawing, circles, polygons etc. If the track drawing command option is active XVI will move the view window to include the location of the last drawing event.
Stay in Client
Any X-Windows application `talks' to the display and is called a client. Any single client application may have a number of separate windows on the display at any time.
To select a client application to track select the Stay in client option from the XVI main dialog (or CTRL + SHIFT +F7). Move the cursor over on of the application windows and press the keys CTRL + SHIFT + <Return>.

The User Preferences Dialog

The user setup dialog allows the setup of various XVI parameters. These parameters are divided into generic groups for ease of use. To set the desired option activate the appropriate button.
The save button saves the current XVI settings. These setting are automatically loaded on startup.
The load button load the last set of saved settings. This is typically used to restore to a known state after experimenting.

The Cursor Setup Dialog

The cursor setup dialog allow the modification of the cursor foreground and background colours. To setup a foreground colour select the foreground radio button. Then either choose one of the fixed colours from the array of given colours or select one by name from the scrolled list.
Load Colours on XVI Startup
This toggle button controls the way XVI sets up the cursor colours on startup. If this button is on then the saved cursor colours are loaded at startup.
The Try button can be used to "try out" the selected colour settings. These setting are only temporary and the original colours are restored if the Cancel button is pressed.

The XVI colours Dialog

The XVI colours dialog allows the look and feel of the XVI application itself to be modified. The selection of colour is performed in the same manner as the cursor colour dialog, select the radio button for the colour to change, then select a colour from the array or list.
The Try button can be used to "try out" the selected colour settings. These setting are only temporary and the original colours are restored if the Cancel button is pressed.

The Background Dialog

The background dialog allow both the colour and pattern of the root window to be modified. Select a pattern from the list of patterns and a colour from the colour selector.
Load Root Window on XVI Startup
This toggle button controls the way XVI sets up the root window on startup. If this button is on then the saved root pattern and colour are loaded at startup.
The Try button can be used to "try out" the selected colour settings. These setting are only temporary and the original colours are restored if the Cancel button is pressed.

Markup created by unroff 1.0,    September 04, 1996.