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tatung
03-06-2001, 07:38 PM
Dear everybody,
i tried to use selection method to select the control points and move them. i can use selection method without gluNurbsSurface function, but, when i use both, the application seems not to work. If you know what's problem, thank you for answer.
tatung

RandyU
03-06-2001, 07:56 PM
WINSDK:"When using gluPickMatrix to pick NURBS, be careful to turn off the NURBS property GLU_AUTO_LOAD_MATRIX. If GLU_AUTO_LOAD_MATRIX is not turned off, then any NURBS surface rendered is subdivided differently with the pick matrix than the way it was subdivided without the pick matrix."
But if you want to select not whole NURBS but only it's knots it's better to place some objects(like balls) in place of control points and then use them in selection mode.

tatung
03-07-2001, 04:40 PM
Originally posted by RandyU:
WINSDK:"When using gluPickMatrix to pick NURBS, be careful to turn off the NURBS property GLU_AUTO_LOAD_MATRIX. If GLU_AUTO_LOAD_MATRIX is not turned off, then any NURBS surface rendered is subdivided differently with the pick matrix than the way it was subdivided without the pick matrix."
But if you want to select not whole NURBS but only it's knots it's better to place some objects(like balls) in place of control points and then use them in selection mode.

Dear RandyU,
thank you very much for greate help, and I have solved the problem. By the way, there are two question.
1. The sentence after "WINSDK" seems a sentence on one book or paper, can you show me where the sentence from? If I could find the related subject, it may be more usefull.

2. There are three kind of display modes (fill, polygon, path). When in fill mode, some selected object(ball) are incorrect. But in polygon or path mode, all the object could be selected correctly. Could some method to solve it?

thank for all response.
tatung

RandyU
03-07-2001, 09:26 PM
I meant WinApi Help that comes with Delphi5, C++Builder and BC5.
As for display modes, do you render NURBS in selection mode? Better render only control points(balls). This bug may be due to both NURBS and ball are selected, and your buffer parser can only tell about one selected object. In Polygon and Patch modes there is less chance of selection NURBS.

EricK
03-08-2001, 07:00 AM
1. The sentence after "WINSDK" seems a sentence on one book or paper, can you show me where the sentence from? If I could find the related subject, it may be more usefull.

You can also get this information directly from the microsoft web site (developer tools). At http://msdn.microsoft.com/vstudio/
search for NURBS. There is a note on gluPickMatrix.