Polyextrude Distance Scale

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Hi, i was wondering why the Local attribues of the Polyextrude doesn't work unless the node is set to Individual Elements. It's a know issue you're planning to fix or is an intented thing? Cause use attributes to control the extrusion is great, but in 50% of the cases is useless if you can't use with Connected Components…

Found a couple of workaround but they apply only if you're starting with a plan geometry at Y=0.
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Hard to say what your problem is. Always easier to help if you post an example file showing your problem.

“Distance Scale” works fine here with “Connected Components”. “Distance Scale” is always multiplied with “Distance” so if “Distance” is 0 the extrusion will be 0. Remember to make a primitive attribute. Point attributes doesn't work with Poly Extrude.


-b

Attachments:
extrudescale.hiplc (73.1 KB)

http://www.racecar.no [www.racecar.no]
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Here's my scene (i'm following the course from Hellolux: Tea and Cookies).

The part for the extrusion start with the Point1 node, where i add a gradient based on the bounding box of the object. Then with a vop i use a ramp to control it. After that i convert the Cd attribute to Primitive (to make it work with the Polyextrude). in the Polyextrude node, as you can see, i'm using the Cd attribute to drive the extrusion based on the gradient, but it has no effect on it. If you try to switch from Connected Component to Individual Elements you'll see that the gradient will work.

Attachments:
Spoon.hipnc (258.3 KB)

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I see. Not sure if Poly Extrude is supposed to give you variable extrusion depth in “Connected” mode. Correct me if I'm wrong.
I would use the “Displace Along Normal” Vop in point mode instead.

-b

Attachments:
Spoon-02.hipnc (272.9 KB)

http://www.racecar.no [www.racecar.no]
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Apparently in previous version (the course was made in Houdini 13) you could set up variables in the Distance paramenters. So you could set $CR or $Cd directly and this systems works. Now that all is shifting to Attributes this is no longer possible. I also found a video made by the authour providing a workaround with an attribute wrangle, using the Y position on the points, but of course this way works only if you need a shift in the Y position, cause the points don't move along their normals.

I've just started to learn Houdini so i didn't thing of Displace along normal as an alternative, i'll try as soon as possible, thanks a lot ^^
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This might be what you need.

PolyExtrude_Rohan_Delvi [vimeo.com]
Werner Ziemerink
Head of 3D
www.luma.co.za
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Feels like it does not work anymore (wth)
there is no Z scale in

reference is not helpful
http://www.sidefx.com/docs/houdini/nodes/sop/polyextrude [www.sidefx.com]

basically same tutorials, same workflow,
tried Rohan's video

might be missing something
Indie 16.5.473

Attachments:
ployextrude-zscale.png (28.2 KB)

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i can't be stuffed going back all the way to check ancient history…here's a simple setup to extrude with zscale

Attachments:
ExtrudeZscale.hipnc (91.3 KB)

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Vusta, thank you!

Random works just fine, will figure out how to control with Cd.r
guess I need to learn basics first //
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While its annoying that this node doesn't just work with connected faces.. its a simple post fix:

  1. drop a rest before the extrude
  2. then do your extrude
  3. After drop a pointVop and set up a ramp to mix back to the rest position based on your ramp values
  4. drop a Fuse if you are ramping back to zero and want to consolidate your points
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