Multiple Extrude V Lofting

[AlanW]

Hi,

In the file multiple extrude between circles and rectangles seems to be resolved by rotating the rectangle by 180 deg but not by lofting,

Any reason and can it be fixed to loft between different shapes smoothly??

And can you smooth out the surfaces between the multiple extrude objects to obtain a similar effect to lofting?

Thanks

Edited May 4, 2016 by Alan Woodwell

[Kevin McAllister]

Alan,

I think part of your issue is that the rectangle has a different curve direction once its converted to NURBS. VW also has issues with the geometry along the short sides of the rectangle when you try to loft the resulting NURBS manually.

This example does speak to a bigger background issue - how does VW determine the direction of a curve when its created. I understand why circles go counterclockwise, since that's how VW sees angles, but why do rectangles go clockwise then? Shouldn't all curves be created in the same direction to prevent these types of issues in scripting?

Kevin

[Marissa Farrell]

Alan,

After reading the explanation Kevin gave, I was able to modify your network to behave a bit better, although you'll have to let me know if it's really what you're looking for.

As for determining which direction NURBS will be created, I have absolutely no idea. This has been an issue when generating contours and it drives me a little bit crazy.

Once I figure out who to ask, I'll try to get back to you with more information. (I was also disappointed to see that we don't offer a node to reverse a NURBS curve... I'll look into that.)

[AlanW]

Marissa, Kevin,

Yes this helps me understand. How do you know which way VW determines the direction of the circle V Rectangles? Is it your programming knowledge. Interested to know and understand myself.

Thnaks

[Kevin McAllister]

Alan,

I just did my regular troubleshooting I would do when a loft doesn't work.....direction (NURBS curves) and normals (NURBS surfaces) are things I'm used to looking for.

Interestingly there was a brief period of time where 2d, non-NURBS curves were showing direction markers too. I guess it was considered a bug since they are no longer visible.

This is what made me realize that all curved had a direction, whether it was visible to the end user or not.

Kevin