<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>hi all;</DIV>
<DIV>I would like to calculate normal vectors of surface points. If <FONT size=2>p0[3], p1[3], p2[3] are coordinates of a surface, Is that code right? Could you please have a look? Thank you...</FONT></DIV>
<DIV><FONT size=2>tony</FONT></DIV>
<DIV> </DIV>
<DIV><FONT color=#0000ff size=2>
<P>double</FONT><FONT size=2> n[3], u[3], v[3],<FONT size=2>p0[3], p1[3], p2[3]</P></FONT></FONT></DIV>
<DIV><FONT color=#008000 size=2>
<P>// Compute two vectors u and v in the cell.</P></FONT><FONT size=2>
<P>u[0] = p1[0] - p0[0];</P>
<P>u[1] = p1[1] - p0[1];</P>
<P>u[2] = p1[2] - p0[2];</P>
<P>v[0] = p2[0] - p0[0];</P>
<P>v[1] = p2[1] - p0[1];</P>
<P>v[2] = p2[2] - p0[2];</P>
<P></FONT><FONT color=#008000 size=2>// Compute the cell non-normalized normal.</P></FONT><FONT size=2>
<P>n[0] = u[1] * v[2] - u[2] * v[1];</P>
<P>n[1] = u[2] * v[0] - u[0] * v[2];</P>
<P>n[2] = u[0] * v[1] - u[1] * v[0];</P></FONT></DIV></div><br>__________________________________________________<br>Do You Yahoo!?<br>Tired of spam? Yahoo! Mail has the best spam protection around <br>http://mail.yahoo.com </body></html>