imakeb(3G)imakeb(3G)NAMEimakeb - registers the screen background process
FORTRAN 77 SPECIFICATION
subroutine imakebPARAMETERS
none
DESCRIPTIONimakeb registers a process that maintains the screen background. Call it
before winope. The process should redraw the screen background each time
it receives a REDRAW event.
There is only one background so only one imakeb process can run at a
time. Any existing imakeb process is killed when a new one is started.
Because the X Window System's inability to change the mode (called the
visual in xspeak) of a window conflicts with the GL's freedom to change
modes at any time, imakebackground imakeb processes cannot paint on the
real background (called the root window in xspeak). Instead a new window
is created with the correct visual. This window is kept at the bottom of
the stack of windows just above the screen background. This
imakebackground imakeb window works better when it is what in xspeak is
called an override-redirect window. In simple terms this means the window
is not managed by the window manager.
A window that is managed is likely to be given borders by the window
manager. Currently only 4Dwm(1X) and mwm(1X) understand the request to
turn off the borders. Also the window manager will post the usual window
menu for a managed window. You cannot access the root menu. A managed
window is useful, however, when the imakebackground imakeb process is
running in color map mode (see cmode(3G)). The window manager is the only
process that can install the GL color map according to its own color map
management policies so that the window is displayed correctly at the
expected times.
Because of this dichotomy, there is an X resource that controls whether
or not the imakebackground imakeb window is managed. The full resource
class is
Name.GL.GLBackground.Manage
Name is the name of the window taken from the argument to winope The
resource can have the values true or false. The default is false. In
other words if the resource isn't specified the imakebackground imakeb
window is not managed. We recommend using managed windows for cmode(3g)
processes and non-managed windows for RGBmode(3g) processes. For example
the following entries in the X resource database
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imakeb(3G)imakeb(3G)
*GLBackground.Manage: false
texback*GLBackground.Manage: true
cause background windows to be unmanaged except for a background program
called texback which is known to be a cmode(3g) program.
SEE ALSO
winope
NOTE
This routine is available only in immediate mode.
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