PseudoColor and DirectColor visuals (was Re: Documentation?)

[Michel Dänzer]

On Thu, 2009-04-09 at 11:17 -0400, Peter Harris wrote:
> Patrick O'Donnell wrote:
> 
> > (Supporting TrueColor, alas, would be a royal pain, given the design
> > of the apps.)
> 
> At least one app I've seen would use an OpenGL fragment shader to do the
> PseudoColor => TrueColor translation at CopyArea[1] time. Instead of
> calling XStoreColors, you would load a new 1D texture and redo the copy.
> Unfortunately, I don't know of a way to bind an X Pixmap into an OpenGL
> texture, so that may not help you any.

FWIW, the GLX extension GLX_EXT_texture_from_pixmap allows binding a
pixmap into an OpenGL texture. It was designed for and is mostly used by
compositing managers like compiz which use OpenGL, but AFAICT it should
be usable for this idea.


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer