<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 style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><style type="text/css"><!-- DIV {margin:0px;}--></style><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;">Hi ,<br><br>Thanx for responding.<br><br> There
is a difference between the Endpoint Knots and Bezier Knots.
Recollecting the theory behind B-Spline(same for NURBS), the "EndPoint"
knot vector would have degree+1 knots at the endpoints alrite. But
there would be many knot spans. It must adhere to the equation m = n +
p + 1 where m + 1 is the number of knots, n + 1 is the number of
control points and p is the degree. <br><br>But in bezier knot
arrangement, there will be total of 2(p+1) control points. so p+1 and
p+1 knots set to 0 and 1 at the beginning and the end of the knot
vector will leave just one knot span. Its within this knot span the
parameter is always within. All of this is for curves...and extended to
surface aswell.<br><br>I am pretty sure there is some bug in the Bezier Knot arrangement.Its a very small bug. But its important.<br><br>Also I need the restriction of the order to be 6 to be removed too.<br><br>Can anyone let me know whom i should contact or which mailing list i should be mailing too?<br><br>The
reason why i am stressing on this is ,i am trying to import and export
bezier and rational surfaces of a particular file format(very much
similar to .off and .obj) that is being used in research in my
university. If these bugs are fixed, then we could use blender more
effectively for our research.<br><br>Thank You,<br><br>Yours Sincerely,<br><br>Siddharth<br><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;">----- Original Message ----<br>From: Bassam Kurdali <bkurdali@freefactory.org><br>To: bf-funboard@projects.blender.org<br>Sent: Friday, December 29, 2006 10:58:19 PM<br>Subject: Re: [Bf-funboard] Restrictions in the order of the
NURBS Surface<br><br><div><br>I think you just need to press the endpoint U and V buttons, the default<br>is the uniform U and V buttons.. it's a nurbs thing, I guess.<br>If it isn't already, this should be in the docs.<br><br>On Fri, 2006-12-29 at 18:49 -0800, Siddharth Palaniappan wrote:<br>> Can anyone advise me as to whom I should be asking these questions? No<br>> one seems to be answering....<br>> <br>> Any help would be greatly appreciated.<br>> <br>> Thanks<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> ----- Original Message ----<br>> From: Siddharth Palaniappan <siddharth_univ@yahoo.com><br>> To: bf-funboard@projects.blender.org<br>> Sent: Thursday, December 28, 2006 11:32:34 PM<br>> Subject: Re: [Bf-funboard] Restrictions in the order of the NURBS<br>> Surface<br>> <br>> Hi,<br>> <br>> I wanted to add that I have noticed that the bezier surface is not<br>> being drawn correctly
on the control grid. Rather I think it leaves<br>> the first row/column of the control grid. Can someone please check<br>> this? The bezier surface(NURBS with bezier knots) should be such that<br>> the surface should interpolate thru the end control points. That is<br>> the end knot vectors should have degree + 1 multiplicity of knots. Is<br>> there anyway , I can set the knot vectors for the surface myself? Is<br>> there a way I can set the knot vector via the Python Script?<br>> <br>> Thank You,<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> ----- Original Message ----<br>> From: Siddharth Palaniappan <siddharth_univ@yahoo.com><br>> To: bf-funboard@projects.blender.org<br>> Sent: Wednesday, December 27, 2006 7:47:07 PM<br>> Subject: [Bf-funboard] Restrictions in the order of the NURBS Surface<br>> <br>> Hi,<br>> <br>> I'm kinda new to blender. I see that there is a restriction in
the<br>> order of 6. I was wondering why this restriction has been placed. Also<br>> I find it wierd to work with bezier knot vector arrangement. For<br>> example, if i have 4 points along U and V(default arrangement) and try<br>> order = 4 along U and V with bezier knot arrangement. I get no patch.<br>> But If i reduce the order to 3 along U and V, i get a patch.(a<br>> quadratic patch) <br>> <br>> I tried increasing the vertices by extruding the edges along U and V<br>> and then used order 4 along U and V. After extruding, we have a 5*5<br>> control net and I get a cubic patch. <br>> <br>> The point is , it seems that there has to be an extra set of points<br>> which are usless when i want a bezier patch. I was wondering if the<br>> term order is wrongly used for degree? After all in bezier<br>> curves/surfaces, order = degree + 1.<br>> <br>> I am currently trying to write an importer/exporter and i find
it<br>> difficult , as certain patches are more than order 6. And also because<br>> of the bezier problem.<br>> <br>> If these problems could be fixed, it would be great since Blender<br>> could be greatly be used in our university in research. I dont know if<br>> the things I mentioned above are bug/problems. If not, please explain<br>> them to me.<br>> <br>> Thank you,<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a rel="nofollow" target="_blank" href="http://mail.yahoo.com/">http://mail.yahoo.com</a> <br>> _______________________________________________<br>> Bf-funboard mailing list<br>> Bf-funboard@projects.blender.org<br>> <a rel="nofollow" target="_blank"
href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br>> <br>> <br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a rel="nofollow" target="_blank" href="http://mail.yahoo.com/">http://mail.yahoo.com</a> <br>> _______________________________________________<br>> Bf-funboard mailing list<br>> Bf-funboard@projects.blender.org<br>> <a rel="nofollow" target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br>> <br>> <br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a rel="nofollow" target="_blank"
href="http://mail.yahoo.com/">http://mail.yahoo.com</a> <br>>
_______________________________________________<br>> Bf-funboard mailing list<br>> Bf-funboard@projects.blender.org<br>> <a rel="nofollow" target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br><br>_______________________________________________<br>Bf-funboard mailing list<br>Bf-funboard@projects.blender.org<br><a rel="nofollow" target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br></div></div><br></div></div><br>__________________________________________________<br>Do You Yahoo!?<br>Tired of spam? Yahoo! Mail has the best spam protection around <br><span><a target="_blank" href="http://mail.yahoo.com">http://mail.yahoo.com</a> </span><br><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;">----- Original Message ----<br>From: Bassam Kurdali
<bkurdali@freefactory.org><br>To: bf-funboard@projects.blender.org<br>Sent: Friday, December 29, 2006 10:58:19 PM<br>Subject: Re: [Bf-funboard] Restrictions in the order of the NURBS Surface<br><br><div><br>I think you just need to press the endpoint U and V buttons, the default<br>is the uniform U and V buttons.. it's a nurbs thing, I guess.<br>If it isn't already, this should be in the docs.<br><br>On Fri, 2006-12-29 at 18:49 -0800, Siddharth Palaniappan wrote:<br>> Can anyone advise me as to whom I should be asking these questions? No<br>> one seems to be answering....<br>> <br>> Any help would be greatly appreciated.<br>> <br>> Thanks<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> ----- Original Message ----<br>> From: Siddharth Palaniappan <siddharth_univ@yahoo.com><br>> To: bf-funboard@projects.blender.org<br>> Sent: Thursday, December 28, 2006 11:32:34 PM<br>> Subject: Re: [Bf-funboard]
Restrictions in the order of the NURBS<br>> Surface<br>> <br>> Hi,<br>> <br>> I wanted to add that I have noticed that the bezier surface is not<br>> being drawn correctly on the control grid. Rather I think it leaves<br>> the first row/column of the control grid. Can someone please check<br>> this? The bezier surface(NURBS with bezier knots) should be such that<br>> the surface should interpolate thru the end control points. That is<br>> the end knot vectors should have degree + 1 multiplicity of knots. Is<br>> there anyway , I can set the knot vectors for the surface myself? Is<br>> there a way I can set the knot vector via the Python Script?<br>> <br>> Thank You,<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> ----- Original Message ----<br>> From: Siddharth Palaniappan <siddharth_univ@yahoo.com><br>> To: bf-funboard@projects.blender.org<br>> Sent: Wednesday, December 27, 2006 7:47:07
PM<br>> Subject: [Bf-funboard] Restrictions in the order of the NURBS Surface<br>> <br>> Hi,<br>> <br>> I'm kinda new to blender. I see that there is a restriction in the<br>> order of 6. I was wondering why this restriction has been placed. Also<br>> I find it wierd to work with bezier knot vector arrangement. For<br>> example, if i have 4 points along U and V(default arrangement) and try<br>> order = 4 along U and V with bezier knot arrangement. I get no patch.<br>> But If i reduce the order to 3 along U and V, i get a patch.(a<br>> quadratic patch) <br>> <br>> I tried increasing the vertices by extruding the edges along U and V<br>> and then used order 4 along U and V. After extruding, we have a 5*5<br>> control net and I get a cubic patch. <br>> <br>> The point is , it seems that there has to be an extra set of points<br>> which are usless when i want a bezier patch. I was wondering if the<br>> term order is
wrongly used for degree? After all in bezier<br>> curves/surfaces, order = degree + 1.<br>> <br>> I am currently trying to write an importer/exporter and i find it<br>> difficult , as certain patches are more than order 6. And also because<br>> of the bezier problem.<br>> <br>> If these problems could be fixed, it would be great since Blender<br>> could be greatly be used in our university in research. I dont know if<br>> the things I mentioned above are bug/problems. If not, please explain<br>> them to me.<br>> <br>> Thank you,<br>> <br>> Yours Sincerely,<br>> <br>> Siddharth<br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a target="_blank" href="http://mail.yahoo.com">http://mail.yahoo.com</a> <br>> _______________________________________________<br>> Bf-funboard mailing
list<br>> Bf-funboard@projects.blender.org<br>> <a target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br>> <br>> <br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a target="_blank" href="http://mail.yahoo.com">http://mail.yahoo.com</a> <br>> _______________________________________________<br>> Bf-funboard mailing list<br>> Bf-funboard@projects.blender.org<br>> <a target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br>> <br>> <br>> <br>> <br>> __________________________________________________<br>> Do You Yahoo!?<br>> Tired of spam? Yahoo! Mail has the best spam protection around <br>> <a target="_blank"
href="http://mail.yahoo.com">http://mail.yahoo.com</a> <br>> _______________________________________________<br>> Bf-funboard mailing list<br>> Bf-funboard@projects.blender.org<br>> <a target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br><br>_______________________________________________<br>Bf-funboard mailing list<br>Bf-funboard@projects.blender.org<br><a target="_blank" href="http://projects.blender.org/mailman/listinfo/bf-funboard">http://projects.blender.org/mailman/listinfo/bf-funboard</a><br></div></div><br></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>