<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">After sending the previous reply to Herbert, I noted some more phenomena which might help someone explain what is going on here.<div><br></div><div>First, while changing the range of the red curve (ycutfcn) from -1 0 to e.g. -2 0 had no effect,</div><div>adding a new curve, identical to this but with range 0 1 (and in my case linestyle=dashed) created a curve on the other side which does go all the way up to the top, as it should.</div><div><br></div><div>Second, though, changing the viewpoint was highly informative. Changing from </div><div>viewpoint=18 65 30 rtp2xyz to viewpoint=18 80 30 rtp2xyz made it clear that the red curve</div><div>is being projected, not onto the red plane, but onto the blue one.</div><div>And changing the second coordinate to a value above 80 (eg 105) made the blue plane and all the curves disappear: I got only the red plane.<br><div>
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<br><div><div>On Aug 30, 2010, at 16:56, Herbert Voss wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Am 30.08.2010 15:43, schrieb Zbigniew Nitecki:<br><blockquote type="cite">Thanks, Herbert.<br></blockquote><blockquote type="cite">I hope that my inclusion of the picture doesn't make this too large to post (I <br></blockquote><blockquote type="cite">am not so adept at posting a picture on my web page).<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">This eliminates the \psset{plan=??}, and (after some fiddling) I managed to get <br></blockquote><blockquote type="cite">the two planes intersecting properly. However, while the first projected curve <br></blockquote><blockquote type="cite">(blue) shows up fine, the second (red) does not. This is true even if I comment <br></blockquote><blockquote type="cite">out all references to the first (blue) plane and the curve on it. I thought that <br></blockquote><blockquote type="cite">maybe it was projecting on the "back side" of the red plane, but it fails to <br></blockquote><blockquote type="cite">appear whether I rotate it 180 degrees or not.<br></blockquote><br>do not use opacity=0, use a value > 0 or didn't use the option.<br>0 means totally transparent, which is the same as not seen.<br><br>However, I do not really understand, why changing the<br>order of the two planes helped. It was more a trial and error<br>methode to find a working example than understanding the<br>problem ...<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,<br>definition=equation,<br>args={[1 0 0 0] 90},<br>base=-2 2 -0.5 4.5,<br>fillcolor=blue!10,<br>name=xplane,<br>ngrid=10 10,<br>action=none<br>]<br>\psSolid[object=plan,<br>definition=equation,<br>args={[0 1 0 0] 180},<br>base=-2 2 -0.5 4.5,<br>fillcolor=red!10,<br>name=yplane,<br>ngrid=10 10,<br>action=none<br>]<br>\psSolid[object=fusion,<br>base=xplane_s yplane_s,<br>]<br>\composeSolid%<br>%<br>\psSolid[object=plan,<br>definition=equation,<br>args={[0 1 0 0] 180},<br>base=-2 2 -0.5 4.5,<br>name=yplane,<br>linewidth=0.5pt,<br>ngrid=10 10,<br>action=none,<br>]<br>\psSolid[object=plan,<br>definition=equation,<br>args={[1 0 0 0] 90},<br>base=-2 2 -0.5 4.5,<br>name=xplane,<br>ngrid=10 10,<br>action=none,<br>]<br>\defFunction[algebraic]{xcutfcn}(y){y*y}{}{}%<br>\psProjection[object=courbe,<br>linecolor=blue,<br>linewidth=2pt,<br>plan=xplane,<br>range=0 2,<br>resolution=720,<br>function=xcutfcn,<br>action=draw**,<br>]<br>\defFunction[algebraic]{ycutfcn}(x){4*x*x}{}{}%<br>\psProjection[object=courbe,<br>linecolor=red,<br>linewidth=2pt,<br>plan=yplane,<br>range=-1 0,<br>resolution=720,<br>function=ycutfcn,<br>action=draw**,<br>]<br>\end{pspicture}<br><br>\end{document}<br><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></body></html>