7 Multiscreen support under Motif

The IDM for Motif has programming support for multiple screens.

Meaning of multiscreen-support under X

This refers to an X server configuration with multiple screens (multiple screens either by one graphics card with multiple frame buffers or by multiple graphics cards in the same display host). The screens can differ in resolution as well as in color capabilities. On the other hand, they share input devices like mouse and keyboard. In addition, their arrangement to each other can usually be defined in the X server configuration (e.g. screen#1 is to the right of screen#0).

Even before, an IDM application could be displayed in a specific screen, e.g. via the X option -display <host>:<display>.<screen>. What is new is that windows can appear in different screens within an IDM application.

Support by the IDM

The IDM supports the application programmer in that he can query the available screens and their characteristics (this is done via the setup object, see also the attributes .screencount, .screen, etc.).

In addition, the IDM allows the assignment of which window is to be displayed on which screen. This is done via the .display attribute on the window. It must be set to a display resource, which is to be defined by the user. The IDM then takes care of the necessary resource management for colors, cursors and images.

Dynamic switching of the window to another screen can be done either via the .display attribute or the display resource. For an example dialog, see also the documentation for the display resource.

Dialog boxes such as message boxes or the file requester are displayed in the same screen as the parent specified in the querybox call. If no parent is specified, the dialog boxes are displayed in the default screen.

Remarks

Unfortunately, the layout of the screens in relation to each other cannot be determined via X/Motif and is therefore not accessible from the IDM.
The IDM's memory requirements are optimized for the standard single-screen application case.
Multiscreen and Non-Default Visuals: The IDM allows the specification of a visual ID via the environment variable IDM_VISUAL_ID in order to use a visual other than the default one (e.g. grayscale screen on a TrueColor display). In a multiscreen configuration, this specification only affects the default screen, i.e. the windows in other screens are displayed in the default visual.
Support for the newly added attributes and resources is now available for the IDM Editor.