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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Thanks for the responses about my not-very-precise request on "Limited</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">precision -- Megapost"</span></font></div>
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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">I am drawing some pictures of light beams falling on different geometric</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">shapes, like parabolas and hyperbolas and "calculating" the reflected beam</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">and, when there are a few reflections involved, I have noticed that these</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">reflected beams fail to pass through the foci of the conics. I think this</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">has to do with precision problems when calculating the intersections of paths, but</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">it can also be due to the representation by cubics, since the conics are</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">drawn by the path joining a few points. I will see if I can do a bit "fine</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">tuning" on this to get acceptable results.</span></font></div>
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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Thanks again and</span></font></div>
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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Many thanks to the developers and to John Hobby for such a wonderful (and</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">enjoyble) piece of software.</span></font></div>
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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Alfredo</span></font></div>
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