Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!BOSCO.BERKELEY.EDU!rusty
From: rusty@BOSCO.BERKELEY.EDU
Newsgroups: comp.windows.x
Subject: color map question
Message-ID: <8806091630.AA02763@velveeta>
Date: 9 Jun 88 16:30:48 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: rusty@cartan.berkeley.edu
Lines: 23

How does one go about printing out the "default" color map?  I'm on a
sun 3/60 (cgfour) running x11r2.  My code looks something like

	dpy = XOpenDisplay(NULL));
	scr = DefaultScreen(dpy);
	scrn = XScreenOfDisplay(dpy, scr);
	nplanes = XDefaultDepth(dpy, scr);
	ncells = XCellsOfScreen(scrn);

	XAllocColorCells(dpy, XDefaultColormap(dpy, scr), 0, plane_masks,
			 nplanes, cmap_cells, ncells);

	for (i = 0; i < nplanes; i++)
		printf("plane_masks[%d] = 0x%x\n", i, plane_masks[i]);
	for (i = 0; i < ncells; i++)
		printf("cmap_cells[%d] = 0x%x\n", i, cmap_cells[i]);

If I run my program after starting up the server all I get is 0's.

The cgfour has a 256 cell color map and I just want to display a 16 by
16 grid with each color of the color map in a square.

Is there a good book that explains the concepts, principals, etc. of
color maps?