Keep orientation when sweeping on a spiral

[mattjakob]

Im trying to sweep a geometry around a spiral I created in VEX but Im having a problem as the cross section slowly rotates.

I tried to set @up and @N attributes and use Transform Using Attributes but it generates other problems.

As you can see the rectangle that Im sweeping rotates over time (I think it does a 360 rotation over the whole path)

 

 

mj_spiral_test.hip

[Atom]

I typically use a polyframe to help out in this situation.

 

[LaidlawFX]

set v@up = {0,1,0};

to brute for the the up angle, and use the polyframe for N like Atom said. This will keep the top edge of your sprial flat if it is going up in the Y axis.

[mattjakob]

thanks guys!

in the end I attached the original straight line as a second input to the sweep and selected 'aim at reference points'. 

@LaidlawFX if I set the up vector to be 0,1,0 then the skeleton instances dont rotate properly along the spline (I think it's called banking ?)

[LaidlawFX]

Cool if you want the banking.