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<p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; "><br class="Apple-interchange-newline">Zbigniew Nitecki</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Department of Mathematics</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Tufts University</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Medford, MA 02155</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; font-size: 12px; "><br></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">telephones:</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Office<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3843</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Dept.<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3234</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Dept. fax<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3966</font></p><span class="Apple-style-span" style="font-size: 12px; "><a href="http://www.tufts.edu/~znitecki/">http://www.tufts.edu/~znitecki/</a></span>
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<br><div><div>On Aug 30, 2010, at 3:15, Herbert Voss wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Am 29.08.2010 20:52, schrieb Zbigniew Nitecki:<br><blockquote type="cite">Is it possible to<br></blockquote><blockquote type="cite">1. Create within one picture projections onto several different planes, and if so<br></blockquote><blockquote type="cite">2. to fuse these?<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">I want (eventually) to draw a paraboloid (say $4x^2+y^2=z$) together with three planes, say the xz and yz planes as well as the plane z=2. In each plane I would like to draw the curve of intersection of the given plane with the paraboloid. I want to make the planes different colors, and to color the curves of intersection with the surface correspondingly.<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">The syntax for projections appears to involve a \psset{plan=??} command, after the definition of the plane of projection, but before the \psprojection command. It looks to me as if the first such declaration supersedes all others. Thus with the code below, I get the (blue) xz=-plane and the curve on it, but then the (red) yz=-plane appears with only the part of it that projects onto the already declared xz plane. If I comment out all the commands giving the xz plane and its curve of intersection with the surface, I get the full (red) yz plane. However (and this is certainly a separate issue) the (red) curve of intersection I have drawn on this does not appear.<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">How can I get both planes, each with its curve, to both appear in a single pspicture, and even better, to have them fuse, so that implicitly it is clear how they intersect with each other?<br></blockquote><br>As far as I know, it is not possible. You can only draw the<br>projections after fusing the two planes.<br><br>\documentclass[11pt]{article}<br>\usepackage{pst-solides3d}<br><br>\begin{document}<br>\begin{pspicture}(-3,-1.5)(3,5.5)<br>\psset{unit=0.35,lightsrc=40 50 50,viewpoint=18 65 30 rtp2xyz,solidmemory}<br>\psSolid[object=plan,definition=equation,args={[1 0 0 0] 90},base=-2 2<br>-0.5 4.5,<br><span class="Apple-tab-span" style="white-space:pre">        </span>fillcolor=blue!10,name=xplane,ngrid=10 10,action=none]<br>\psSolid[object=plan,definition=equation,args={[0 1 0 0]},base=-2 2 -0.5<br>4.5,<br><span class="Apple-tab-span" style="white-space:pre">        </span>fillcolor=red!10,name=yplane,ngrid=10 10,action=none]<br>\psSolid[object=fusion,base=xplane_s yplane_s]<br>\composeSolid%<br>%<br>\psSolid[object=plan,definition=equation,args={[1 0 0 0] 90},base=-2 2<br>-0.5 4.5,<br><span class="Apple-tab-span" style="white-space:pre">        </span>name=xplane,ngrid=10 10,action=none]<br>\defFunction[algebraic]{xcutfcn}(y){y*y}{}{}%<br>\psProjection[object=courbe,<br><span class="Apple-tab-span" style="white-space:pre">        </span>linecolor=blue,linewidth=2pt,<br> plan=xplane,range=-2 2,resolution=720,function=xcutfcn,<br> action=draw**]<br>\psSolid[object=plan,definition=equation,args={[0 1 0 0]},base=-2 2 -0.5<br>4.5,<br><span class="Apple-tab-span" style="white-space:pre">        </span>name=yplane,linewidth=0.5pt,ngrid=10 10,action=none]<br>\defFunction[algebraic]{ycutfcn}(x){4*x*x}{}{}%<br>\psProjection[object=courbe,<br><span class="Apple-tab-span" style="white-space:pre">        </span>linecolor=red,linewidth=2pt,<br> plan=yplane,range=-1 1,resolution=720,function=ycutfcn,action=draw**]<br>\end{pspicture}<br><br>\end{document}<br><br>Herbert<br>_______________________________________________<br>PSTricks mailing list<br><a href="mailto:PSTricks@tug.org">PSTricks@tug.org</a><br>http://tug.org/mailman/listinfo/pstricks<br>archive: http://www.tug.org/pipermail/pstricks/<br></div></blockquote></div><br></div></div></body></html>