Re: Scoring visuals in GdkRGB

[Owen Taylor <otaylor redhat com>]

Keith Packard <keithp keithp com> writes:

> Around 20 o'clock on Jul 10, Owen Taylor wrote:
> 
> > 8-bit pseudocolor one.  It allocates its 6x6x6 color cube,
> 
> That's a crazy amount of pseudo color space to allocate; presumably the 
> poor slob is using a pseudo color visual because they have to for some 
> legacy apps.  I whacked Render down to a small handful on such visuals; 
> the result totally sucks, but at least the legacy apps continue to work.

When the code was originally written (97 or so) is was still relatively
common to have people trying to run, say, the GIMP and Netscape on a 8-bit card,
so filling most of the system colormap with a color cube that could be
shared made some sense.
 
> btw -- you can query Render's colormap entries and use them for Gdk if you 
> like; that would avoid allocating two blocks of colors from the default 
> colormap.
 
Considering that people who are up-to-date enough to have render
probably aren't the main target for 8-bit rendering, I'm not sure this
is worth the complexity. (Would require some sort of 

 _gdk_visual_get_recommended_color_cube()

call since GdkRGB is backend independent.)

> I create a relatively small cube and then allocate a range of gray values 
> in addition; this isn't great, but having a reasonable set of gray values 
> really helps AA text.

Supporting that would require some mucking around inside GdkRGB - currently
it does grayscale by converting it to color temporarily, and then rendering
the color.

Regards,
                                        Owen