🚀 go-pugleaf

> Constructing the colormap is not a problem.  I can't figure out how to
> use it.  I have tried two things:
> 
> i)  cmap=XCreateColormap(display,window,visual,AllocAll);
> 
> 	Whenever I use AllocAll in this call it does something funky
> 	to display.  The side effect is that it bombs when it hits
> 	XNextEvent(display,&e).  Reason?

Hmmm.... Does something funky to display.... bombs....   hmmm...  my crystal
ball suggests that perhaps you're specifying a visual type that doesn't 
allow read/write allocation. Try reading about visuals, try using the function
XGetVisualInfo or XMatchVisualInfo, try looking for error messages and try using
a debugger.


> ii) cmap=XCreateColormap(display,window,visual,AllocNone);

      with the following (paraphrased by the answerer):
      XAllocColorCells(display, cmap, False, NULL, 0, pixels, ncolors);

> It didn`t seem to work
> for any value of ncolors (I put it in a loop from 256 down to 0).

Maybe the colormap was created with a visual type that doesn't allow read/write
allocation from the colormap.  


> Finally, when I actually do get around to building the virtual colormap
> successfully, do I use XInstallColormap or XSetWindowColormap?

XSetWindowColormap.


Donna Converse
converse@expo.lcs.mit.edu