On Thursday 21 February 2002 3:32 pm, Martin Vermeer wrote: > On Thu, Feb 21, 2002 at 02:00:41PM +0000, Angus Leeming wrote: > > > On Thursday 21 February 2002 1:39 pm, Asger K. Alstrup Nielsen wrote: > > > On Thu, 21 Feb 2002, Angus Leeming wrote: > > > > > > > and the problem is now defining an appropriate mapping from the colour > > > > colourmap to a grayscale or monochrome one. > > > > > > I'm not sure what the problem is, but if you want to convert from > > > color to grayscale, just do this: > > > > > > int gray = (red + blue + green) / 3; > > > > > > If you want to go monochrome, do this: > > > > > > bool black = gray >= 128; > > > > > > Greets, > > > > > > Asger > > > > Thanks, Asger. I was playing already! > > A > > Hmm, I remember John Levon published a script for doing this automatically. > > http://www.movement.uklinux.net/patches/lyx/xpm.diff > > Martin
Nice! However, in general, a converted file will only have c_colors. We need to generate the m_color or g_color entries on the fly if libXPM is to display monochrome or grayscale images. Now done. Angus
