Poly extrude along curve

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Hi there,

I was following this tutorial https://vimeo.com/142470680 [vimeo.com] but the extrude just doesn't behave like in the video. The extruded object seems to be in the right shape (except the start), but in a different scale/rotation/position. What am I missing? This should be super straight forward, right? Sorry if this has been answered before.


a placed box, the curve. selected face is 3.


The resulting gemoetry doesn't match the curve.

Attached you'll find the simple scene file, but its essentially the exact same steps than in the movie.

Thanks!
Edited by Xue_Yue - Sept. 24, 2018 11:49:11

Attachments:
curve_extrude.hip (118.5 KB)

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Actually i don't know if it even shoul'd be on the curve. (But i am a starter…and i don't know many nodes yet.)
Anyway here is your Scene file re-saved as *.hipnc(sorry only Apprentice here) with one added switch node, state 0 is a grid(a face) extruded along curve1(through a sweep node and some other nodes(inside the subnet).

Hope this helps somewhat.
Image Not Found
Edited by mouse_art - June 20, 2018 18:12:50

Attachments:
curve_extrude_switch_sweep.hipnc (132.9 KB)
Capture.PNG (857.3 KB)

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Thanks, yes that sweep works well.

I just wondered why it is now so different than in the tutorial (there the geo was definitely on the curve).

There must have been some changes to the polyextrude node, and I wanted to understand what it is. Because I would think that it should behave like your sweep-setup. The odd scaling/translating doesn't really make sense to me and renders the “extrude along curve” pretty much useless for most cases, right?

Cheers!
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When you set up a curve in the second input that curve will be “fit” between the start point of the extrude to the “extruded front” which is by default a certain distance from the start based on the distance attribute.

In the attached file, I turned on “Transform Extruded Front” in the Extrusion tab which freed up the front to be moved anywhere I wanted so I point snapped it to the end of the curve. I then used the rotate handle to rotate the end face to align with the curve. This gives you something much closer to what you wanted.

In the tutorial this wasn't needed because the endpoints of the input curve were both aligned along a straight line so the distance attribute did the trick. Since your endpoints are not aligned, the Transform Extruded Front option was necessary.

Attachments:
polyextrude_curve.jpg (350.2 KB)
curve_extrude_02.hip (121.6 KB)

Robert Magee
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