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<DIV><FONT size=2 face=Arial>Hello, Amin.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial><FONT size=3 face="Times New Roman">>If you
don't mind I would like to ask you another question, that is - whether it is
possible to define Line >Loops using Spline/Bspline curves which makes a
surface with more than 4 edges.</FONT></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I think it is impossible. The manual
sais:</FONT></DIV>
<DIV><FONT size=2 face=Arial><SPAN
style="WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; BORDER-COLLAPSE: separate; FONT: medium 'Times New Roman'; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px"
class=Apple-style-span>
<DT><CODE></CODE> </DT>
<DT><CODE>Ruled Surface (<SPAN
class=Apple-converted-space> </SPAN></CODE><VAR>expression</VAR><CODE><SPAN
class=Apple-converted-space> </SPAN>) = {<SPAN
class=Apple-converted-space> </SPAN></CODE><VAR>expression-list</VAR><CODE><SPAN
class=Apple-converted-space> </SPAN>} < In Sphere {<SPAN
class=Apple-converted-space> </SPAN></CODE><VAR>expression</VAR><CODE><SPAN
class=Apple-converted-space> </SPAN>} >;</CODE><A
name=index-Ruled-Surface-_0028-_0040var_007bexpression_007d-_0029-_003d-_0040_007b-_0040var_007bexpression_002dlist_007d-_0040_007d-_003c-In-Sphere-_0040_007b-_0040var_007bexpression_007d-_0040_007d-_003e_003b-241></A></DT>
<DD>Creates a ruled surface, i.e., a surface that can be interpolated using
transfinite interpolation. The<SPAN
class=Apple-converted-space> </SPAN><VAR>expression</VAR><SPAN
class=Apple-converted-space> </SPAN>inside the parentheses is the ruled
surface's identification number; the first<SPAN
class=Apple-converted-space> </SPAN><VAR>expression-list</VAR><SPAN
class=Apple-converted-space> </SPAN>on the right hand side should contain
the identification number of a line loop composed of either <U><FONT
color=#ff0000>three (!)</FONT></U> or <U><FONT
color=#ff0000>four (!)</FONT></U> elementary lines. The optional<SPAN
class=Apple-converted-space> </SPAN><CODE>In Sphere</CODE><SPAN
class=Apple-converted-space> </SPAN>argument forces the surface to be a
spherical patch (the extra parameter gives the identification number of the
center of the sphere).</DD></SPAN></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial><FONT size=3 face="Times New Roman">>I am
willing to make a 3D grid around a NURBS surface (in .igs format) which is made
up of several >surfaces defined by BSpline curves. I am trying to make those
surfaces Transfinite and after making those >transfinite I am hoping to
extrude those surfaces so that it makes a 3d grid. But I am finding it difficult
to >define those NURBS surface components into Transfinite surfaces (I am
trying to make structured grid). <BR></FONT></FONT></DIV>
<DIV><FONT size=2 face=Arial><FONT size=3 face="Times New Roman"><FONT size=2
face=Arial>I'm not sure that I understood your question rightly
but</FONT> <FONT size=2 face=Arial>I attach an example where I created
a Transfinite Surface bordered by four BSpline
lines. H</FONT></FONT>ope this helps.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2>Mikhail
Artemiev</FONT></DIV></FONT></BODY></HTML>