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vjfrost
05-17-2001, 02:35 AM
I tried to create an object with NURBS by rotating some vertices around the z axis. That means if have lets say four vertices:
0.0 / 0.0 / 1.0
1.0 / 0.0 / 1.0
1.0 / 0.0 / -1.0
0.0 / 0.0 / -1.0
These build a curve in positive x direction.
Now as I said I let them rotate around z so the next 3 steps would be:
0.0 / 0.0 / 1.0
0.0 / 1.0 / 1.0
0.0 / 1.0 / -1.0
0.0 / 0.0 / -1.0
,
0.0 / 0.0 / 1.0
-1.0 / 0.0 / 1.0
-1.0 / 0.0 / -1.0
0.0 / 0.0 / -1.0
and
0.0 / 0.0 / 1.0
0.0 / -1.0 / 1.0
0.0 / -1.0 / -1.0
0.0 / 0.0 / -1.0

Finally I guessed it should result in something like a sphere as soon as I close this object by giving a 5th curve that has the same vertices as the first...
But it doesnt!
It looks like the first/last vertices have a 'higher weight' because the model is stretched in that direction.
Is this normal behaviour? And how can I solve my problem...?

(Sorry for all the 0 and 1 :-)