[comp.windows.x] Another TWM colormap problem: ximag

thompson@ux1.cso.uiuc.edu (03/02/90)

NCSA XImage attempts to make various releases of window managers happy.  
To maintain backward compatibility to those window managers that did 
not comply with ICCCM for handling palettes, ximage does an XInstallColormap().
For compatibility with those window managers that are ICCCM compliant
when setting colormaps, ximage sets a Colormap attribute on the window 
using XSetWindowColormap().  This method appears to work with the 
window managers that I've tested.  They include mwm from Motif 1.0,
olwm from OpenWindows 1.0, uwm R3, tekwm, gwm, and wm R3.  Of course,
colormaps are also properly set when no window manager is running
using this method.

Removing the XInstallColormap() calls in XImage seems to eliminate
colormap setting problems when using twm.  When XImage does an 
XInstallColormap(), it appears that twm senses this and then installs 
the default colormap rather than the appropriate colormap set as an attribute 
for the window.  It's unfortunate that twm behaves this way because
it limits the clients ability to handle the many different window managers
that users may use without user intervention.  Version 1.0.4 of XImage 
(due out in less than a month) will determine colormap setting policies
from the resource database.

Dave Thompson

National Center for Supercomputing Applications	
605 East Springfield Ave      Internet: davet@ncsa.uiuc.edu
Champaign, IL 61820	        Usenet: {ihnp4,convex}!uiucdcs!zaphod!davet 
voice (217) 244-1957		Bitnet: 14011@NCSAVMSA.BITNET
fax   (217) 244-1987		 CSNet: thompson%uxe@uiuc.csnet