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<div> <font color="black" face="Arial, Helvetica, sans-serif" size="2"><pre style="font-size: 9pt;"><tt>Leon Free Wrote :<br>
>i want to obtain the same result when the vertical plane P need not be
>parallel to one of the axis, ie P={(x,y,z) : ax+by+c=0} with a,b both
>nonzero (and (obivously) has a non empty intersection with the surface)</tt></pre></font><br>
A first draft. Uncomment the following lines to write the files. dat<br>
<br>
\documentclass{article}<br>
\usepackage[dvipsnames,svgnames]{xcolor}<br>
\usepackage{pst-solides3d}<br>
\begin{document}<br>
\begin{center}<br>
%\codejps{<br>
%/biface false def<br>
%-.5 3 0.85 3.5 [0.2 0.2]<br>
%{/y exch def<br>
% /x exch def<br>
% -0.35 x dup mul mul<br>
% y 2 sub y 1.5 sub mul sub<br>
% 0.2 x mul y mul add<br>
% 4.5 add }<br>
% true<br>
% newsurfaceparametree<br>
%(Surface) writesolidfile<br>
% }<br>
\begin{pspicture}(-4,-4)(7,10)<br>
\psset{lightsrc=viewpoint,viewpoint=100 35 30 rtp2xyz,Decran=150}<br>
%\psset{solidmemory}<br>
%\psSolid[object=datfile,<br>
% file=Surface,<br>
% plansepare={[0.707 0.707 0 -2.5]},<br>
% name=surface,<br>
% action=none]<br>
%\psSolid[object=load,<br>
% load=surface1,<br>
% file=surface1,action=writesolid]<br>
%\psSolid[object=load,<br>
% load=surface0,<br>
% file=surface0,action=writesolid]<br>
\axesIIID(0,0,0)(5,5,7)<br>
\psSolid[object=datfile,<br>
hollow,<br>
rm=0,<br>
file=surface1]<br>
\psSolid[object=plan,<br>
definition=equation, args={[0.707 0.707 0 -2.5] },opacity=.5,<br>
plangrid,<br>
fillcolor=ForestGreen!20, linecolor=gray!50,base=-6 0 -6 0]<br>
\psSolid[object=datfile,<br>
hollow,<br>
rm=0,<br>
intersectiontype=0,<br>
intersectionplan={ [0.707 0.707 0 -2.51] },intersectioncolor=(rouge),<br>
intersectionlinewidth=2,<br>
file=surface0](0,0,0)<br>
\end{pspicture}<br>
\end{center}<br>
\end{document}<br>
<br>
<br>
ML<br>
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