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<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'>Can anyone give
me some hints on how to calculate the intersection of two or more surfaces? In
other words I want the &#8220;object&#8221; that results from the locus of points common to
the surfaces. </span></font><font size=2 color=black face="Courier New"><span
lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;
mso-color-alt:windowtext;mso-ansi-language:EN-US'><o:p></o:p></span></font></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'><![if !supportEmptyParas]>&nbsp;<![endif]></span></font><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-color-alt:windowtext;mso-ansi-language:
EN-US'><o:p></o:p></span></font></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'>Probing seems to
return a band mapped onto the input surface consisting of the scalar range of
the source surface. So if the source was planar this would be Ok.</span></font><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-color-alt:windowtext;mso-ansi-language:
EN-US'><o:p></o:p></span></font></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'><![if !supportEmptyParas]>&nbsp;<![endif]></span></font><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-color-alt:windowtext;mso-ansi-language:
EN-US'><o:p></o:p></span></font></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'>Thanks</span></font><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-color-alt:windowtext;mso-ansi-language:
EN-US'><o:p></o:p></span></font></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-ansi-language:EN-US'><span
style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </span>Andrew</span></font><font
size=2 color=black face="Courier New"><span lang=EN-US style='font-size:10.0pt;
font-family:"Courier New";color:black;mso-color-alt:windowtext;mso-ansi-language:
EN-US'><o:p></o:p></span></font></p>

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face=Arial><span style='font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
Arial'><![if !supportEmptyParas]>&nbsp;<![endif]><o:p></o:p></span></font></span></p>

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