cde/cde/examples/dtscreen

/* $XConsortium: README /main/3 1996/07/15 14:01:10 drk $ */

This directory contains demonstrations of the Dt Screen Saver API

screensaver -	Example of a simple screen saver that uses the DT Screen
		Saver API and techniques to make that screen saver
                available to all desktop users or your own session.

                The desktop provides a set of screen savers for use
                in desktop sessions. This set of screen savers can
                be previewed and selected from the Style Manager Screen
                dialog. 

                Each screen saver is known to the desktop by the screen
                saver's action definition. The screen saver's action 
                definition provides the desktop with a short localizable
                title for the screen saver, as well as the command line
                and options required to start the screen saver. When the
                desktop starts a screen saver, it is started by invoking a
                screen saver action. 

                The set of screen saver actions available to a user's 
                desktop session is defined by the DTSCREENSAVERLIST
                environment variable. The default DTSCREENSAVERLIST
                set is defined when you start a desktop session. A
                system administrator can change this set by creating
                a script in directory /etc/dt/config/$LANG/Xsession.d 
                that modifies DTSCREENSAVERLIST. A user can do the
                same in their $HOME/.dtprofile.

                A desktop screen saver is a simple application that
                uses the DtSaverGetWindows() API to obtain a list of
                windows, and draws on those windows. The desktop handles
                the starting and stopping of the screen saver application.
              
                The 'screensaver' application is an example that shows 
                how the DtSaverGetWindows() API may be used, how the 
                screen saver action may be defined for 'screensaver' and
                how the screen saver can be integrated into the desktop for
                all desktop users or an individual desktop user. The screen
                saver action is named SampleScreenSaver and is defined in
                /usr/dt/examples/dtscreen/dt/appconfig/types/C/screensaver.dt.

                Making the screen saver available to all users
                ----------------------------------------------
                You must be root to make the screen saver available
                to all users. This example assumes you are building
                'screensaver' directly in /usr/dt/examples/dtscreen.

                1) Build the 'screensaver' application
      
                   make -f Makefile.<platform>

                2) Register the screen saver action with the desktop

                   dtappintegrate -s /usr/dt/examples/dtscreen

                3) Add the screen saver action to the list of available savers

                   #create file /etc/dt/config/Xsession.d/myvars containing:
                   DTSCREENSAVERLIST="SampleScreenSaver $DTSCREENSAVERLIST"

                4) Make the /etc/dt/config/Xsession.d/myvars file executable:

                   chmod 755 /etc/dt/config/Xsession.d/myvars

                The next time a user starts the desktop, the example screen
                saver will be available for use.
                     
                Making the screen saver to your own desktop session
                ---------------------------------------------------
                1) Copy the screen saver example to $HOME/dtscreen

                   cp -r /usr/dt/examples/dtscreen $HOME/dtscreen
                   cd $HOME/dtscreen

                2) Build the 'screensaver' application

                   make -f Makefile.<platform>

                3) Register the screen saver action with the desktop
 
                   cp $HOME/dtscreen/dt/appconfig/types/C/screensaver.dt \
                     $HOME/.dt/types

                4) Change the action EXEC_STRING path

                   vi $HOME/.dt/types/screensaver.dt
                   #change the EXEC_STRING to '<home>/dtscreen/screensaver',
                   #replacing <home> with the value of $HOME

                5) Add the screen saver action to the list of available savers

                   #edit $HOME/.dtprofile and add:
                   DTSCREENSAVERLIST="SampleScreenSaver $DTSCREENSAVERLIST"

                The next time a user starts the desktop, the example screen
                saver will be available for use.