Meta screen

Although XbigX eliminates the borders between the screens of an X Window server, it may offer multiple separate display areas, so-called meta screens, to the clients. For instance, screens with different graphics capabilities may be grouped to several meta screens. In the statement

metaScreen name

name is an arbitrary string. Each meta screen corresponds to a screen number, increasing from .0 on.

Without this statement, the xbigx program creates all meta screens referred to by any screen definition, at least one.

The metaScreen statement introduces sub-statements, which specify additional parameters of the meta screen.

The sub-statement

    delete

removes a meta screen from a configuration.

Position of a meta screen

Like most X Window servers, XbigX allows to move the mouse pointer from one display area (here meta screen) to an other. For determining the neighboring meta screen, the relative positions of all meta screens must be known. The sub-statements

    northOf|northEastOf|eastOf|sourthEastOf|southOf|southWestOf|westOf|northWestOf
name_of_a_meta_screen
[horizontal_offset_in_pixels vertical_offset_in_pixels]

define the position of a meta screen relative to an other one. Cyclic definitions are not allowed. The offset parameters default to the value 0. Without a position specification the meta screen is positioned right to the preceding one, with the exception of the first one.

Dimensions of a meta screen

The sub-statements

    width width_in_pixels|double
height height_in_pixels|double

define the dimensions of the virtual display area of a meta screen. The default values of 0 have the special meaning that the area is just big enough to enclose the associated screens (Position of a screen). These dimensions can be doubled by specifying double.

In most cases only partly displaying a meta screen yields no problems. However, only for total compliance with the X11 protocol, the whole display area of the meta screen should be covered by screens, and it should be visible. The mouse pointer cannot be positioned on invisible areas, except using dynamic positioning of a screen (Dynamic position of a screen). Furthermore, some X Window clients show bugs, if they should draw to invisible areas (Drawing actively) (Ignoring Expose events).

The sub-statement

    keepWindowsVisible number_of_pixels

determines that at least an area of number_of_pixels pixels in both dimensions of each window remains within the visible part of the meta screen, even if it is positioned at an invisible position or if a screen is deleted from the configuration. This works only with window managers compliant to the ICCCM (Inter-Client Communication Conventions Manual) or without any window manager, in rare cases a workaround (Buggy window manager) may be necessary. The default value 0 for number_of_pixels disables this function.

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