🚀 go-pugleaf

In article <1993Jan26.003950.5073@sol.ctr.columbia.edu> csysmw@scs.leeds.ac.uk (S M Wombwell) writes:
>
>
>Hello there,
>	I am trying hard to programme a 3D sculpture package in Iris Inventor
>using the language C++. I have a problem that I need help with:

Okay, first of all make sure to read Chapter 8 of the Inventor Programming 
guide. It has general instructions and four examples of how to use 
Inventor NURBS.

>   1.	Is there anyway to use the drag pointer with NURB surfaces?

Yes. When the SoNurbsSurface node draws, it looks in the current coordinates 
(i.e., the most recent SoCoordinate3 node) for the control points.  See 
Chapter 8 and the man pages to find out which coordinate corresponds to 
which control point.

Once you know the control point you want to move, you can attach a dragpoint
manipulator to that point as follows:

myDragPoint->attach( pathToCoordinateNode, indexOfPointToEdit );

The path should go from the scene root down to the SoCoordinate3 node.
The index should be the index of the control point you need to edit.

I haven't tried this exact example, but it should work fine. As you move the
manipulator, the NURB should change to be influenced by the control point.
Let me know if you have a problem. 

>   2.	Has anyone got any predefined shapes using NURB surfaces? (ie cones,
>	spheres, cylinders etc)

Inventor ships only one NURBS object. It should be installed as 
/usr/data/models/teapot.iv


>   3.   Is there an easy way to merge two NURB surfaces?	

I haven't worked with NURBS myself. As I understand it this is a 
general NURBS question, not an Inventor question. Is that correct?
I think you just have to make sure that their control points match along
a shared edge, but I'm not sure.

>Your help is much appreciated
>
>  -= Stephen =-