How to I extrude points to make edges ?

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Hello everyone, I'm new here and also quite new with Houdini.

I have a bunch of points with normals and I would like to extrude them into edges along the direction of their normals. How do I do that in Houdini ?

Thank you for your time.
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try polyextrude
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Could you please go in detail ? I tried to scatter some points and then give them normals in order to extrude them but adding poly extrude does not return edges as expected.

Thanks.
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Are the points connected? polyextrude only works on polygonal geometry, not disconnected points.
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jsmack
Are the points connected? polyextrude only works on polygonal geometry, not disconnected points.

The points are disconnected, I was looking for a may to build edges based and scattered points with normals.

If poly extrude does not work what are my options ?

Thanks.
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in the attribute wrangler there is an example for crating hair . Have look at that, basically. you will need to duplicate your point, offset it along your normal, then build a line in between.
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The points are disconnected, I was looking for a may to build edges based and scattered points with normals.

If poly extrude does not work what are my options ?


After your scatter you can create a group of points you will want for your ‘edge’.

Then use an add SOP with the folder TAB ‘By Group’ selected, and specify the group name you created beforehand, putting it in the Add nodes Group parameter.

Then you now have a polyline which you can use with the polyextrude. If you want too, just after the add node you can put in a Resample node.
Edited by BabaJ - Jan. 7, 2020 13:59:32
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Here's an example for that.
Scattered some points, added a randomized Normal, gave it a number-attribute, displaced the points along a normal with a adjustable amount, the merged them back with the original points, and with an add sop, using “number” as group by attribute, tada.
Hope this helps.
Cheers,
Rudi

Attachments:
GrowPolyFromPointWithNormal.hip (187.0 KB)

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Thanks everyone, duplicating with an ID and using the add node with the By Group option did the the trick for me.

Thanks again.
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Even simpler if you copy lines ⚟ on points. You can have lot more control on the direction and length of the lines.
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