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From: Ethan A Merritt <EAMerritt@gmail.com>
Newsgroups: comp.graphics.apps.gnuplot
Subject: Re: How to properly visualize polygons by splot ?
Date: Tue, 02 Jun 2015 08:33:04 -0700
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Lukas Placek wrote:

> Hello everybody,
> I am trying to visualize some polygons in 3D. When I rotate the
> visualized polygons, the rendering is obviously done wrongly. It looks
> like the polygons are drawn in the order I defined them and not from
> back to front.

Correct. Gnuplot draws objects in the order the are defined, not
based on coordinates.  Also gnuplot does not calculation occlusion
of solid objects, except for the case of surfaces drawn with
"set hidden3d".


> Does anybody know what needs to be done to get the
> right rendering ? Thank you very much Lukas
> 
> I draw polygons by this command:
> set object  1 polygon from   0.912E-01,   0.331E-01,  -0.327E-01 to  
> 0.913E-01,   0.328E-01,  -0.324E-01 to   0.917E-01,   0.327E-01, 
> -0.323E-01 to   0.917E-01,   0.331E-01,  -0.326E-01 to   0.912E-01,  
> 0.331E-01,  -0.327E-01    fillstyle solid border 15 fillcolor rgb
> "#8B8989"
> 
> and use splot to view what I have drawn.