[Plplot-devel] Re: PerlDL: Re: Cannot get rgb to work

[Craig D. <def...@bo...>]

Quoth Rafael Laboissiere on Friday 01 October 2004 06:00 am,
> Plotting RGB images is not possible currently in PLplot.  There has been
> some discussion about this in the plplot-devel, but no concrete
> implementation has been proposed.

Hmmm... I'm not (yet) familiar with the PLplot architecture but... the PGPLOT
problem was that the virtual devices were all written with 256-value 
pseudocolor in mind.  I observed that most modern display devices have
persistent color -- once you change the color map, the original pixels remain,
since the device just maps the pseudocolor map back to RGB space.  So
RGBI works by setting 200 entries in the color table, and then clocking out a 
set of 200 pixels with value 56..255.  Lather rinse repeat until all the 
pixels in the image have been plotted.  Slow but at least it works.

In the long run, one would (of course) want a better architecture, but my 
objective was to get something working fast.