Re: [Gnuplot-info] maxima + gnupolot: 3D rendering bug?

[Stanislav M. <sta...@gm...>]

Hello,

On Tue, 2010-12-07 at 15:42 +0000, Stanislav Maslovski wrote:
> On Tue, 2010-12-07 at 11:51 +0000, Stanislav Maslovski wrote:
> > Hello,
> > 
> > Can anyone advise me on how can I workaround the problem with 3D
> > rendering in the plot [1]? The problem is that the surfaces that must be
> > hidden are seen in this plot (to clearly see them,
> > load "maxout.gnuplot" and try rotating the plot).
> > 
> > The plot was generated in maxima, using the draw3d command. Any help
> > will be very much appreciated!
> > 
> > [1] http://zalil.ru/30094104 (wait 10 secs, and download will start)
> 
> Replying to myself: actually, after reading some docs (and the code) I
> realized that it was a limitation of the rendering algorithm used by the
> gnuplot (a variant of painter's algorithm). So, I solved this issue by
> patching pm3d.c:pm3d_depth_queue_flush() so that sorting of quadrangles
> was done based on the average depth of 4 corners.
> 
> It would be nice if this could be made configurable. I will probably
> come out with a patch in the next couple of days to enable this feature.

Just in case: the patch with an example is available from here
http://sourceforge.net/tracker/?func=detail&aid=3132649&group_id=2055&atid=302055

Cheers,
--
Stanislav