Re: Problem with mesh plots and hidden line removal

[Kai H. <kai...@gm...>]

Ethan Merritt schrieb:
> On Friday 07 March 2008 03:38, Kai Habel wrote:
>   
>> Hello,
>>
>> I noticed the following problem in octave3.0.0/gnuplot4.2.2 using the wxt terminal. 
>> When I try to plot a 3D mesh with "hidden on" and a rgb color set, only the white 
>> facets without grid are drawn.  
>>
>> if I use
>>    'set style line 1 default;'
>> instead of
>>    'set style line 1 linewidth 0.500000 pointsize 1.000000 linecolor rgbcolor "#FF00FF";'
>> and 'set hidden' it works as expected - a grid, with hidden line removal and the 
>> default (green) color is drawn. 
>>
>> Is this a bug in the script or a gnuplot problem?
>>     
>
> A bit of both. The issue is that the colors for hidden-surfaces are
> auto-generated based on the line _type_,  but you gave an splot
> command using a line _style_.   Bad luck that it somehow ends up choosing a
> linetype lt -2 or -3 (background color or no line).
>
> This is supposed to be fixable using the command
> 	set style increment user
> (which is a truly horrible name for a command;  kudos to anyone who
> can suggest a better one so that we can deprecate this).  This command
> causes the user-defined line _styles_ to be substituted everywhere a line
> _type_ would normally be used.  
>
> So much for the script buglet.  Unfortunately, the hidden3d code in
> 4.2.2 fails to notice when you set this flag, although the CVS version
> gets it right.  The fixed code will be in 4.2.3, which should be out
> "real soon now".
>
> 	Ethan
>
>   
Hello Ethan,

thanks for your quick reply. After including the sequence "set style
increment user" and using 4.2.3 I was able to plot the uniform colored
mesh with hidden3d.

Kai