Hi, Houdini has a few methods for determining orientation along a curve.
- The default orientation for a circle in Houdini is the XY plane which also happens to match the default sweep settings. If you change the circle orientation, you'll get different results. (Which might be what you are seeing in Modo)
- If your circle (or whatever shape you are using) is at a different orientation, you can use the options in Sweep to adjust it. (Construction Tab > Up Vectors)
- An alternative method would be to use the Orientation_Along_Curve sop on the curve before it goes into the sweep.
Regarding your second question:
Moving a circle to the start point of a curve is not really how a sweep is used. If you offset the position of a circle from 0,0,0 before it goes into a sweep, the sweep will be offset by the same amount.
What you are describing could be a method of using a polyextrude as a sweep alternative which requires the start and end points of the curve to match the front & back of an extrude.
Extrude along curve:
https://www.sidefx.com/forum/topic/56419/?page=1#post-254260 [
www.sidefx.com]
Regarding your third question:
If you have 12 points along a curve and you want to smooth them procedurally. You can use either of the following sops:
- Smooth (curve has same 12 points)
- Subdivide (curve now has 23 points)
- Resample (set to Subdivision Curves)
- Polybevel (set to points)
Note: Sweep can use multiple cross-sections if you want extra control over the start/middle/end of a sweep.
Multiple cross-sections:
https://www.sidefx.com/forum/topic/70970/?page=1#post-301394 [
www.sidefx.com]
Rob