Multi-segment curves in Unreal

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When creating a Houdini Engine asset in Unreal you can specify a SOP input as a curve input. Once you choose curve input Houdini Engine presents you with a lot of options: Polygon, Nurbs, Bezier, CVs, Freehand, Breakpoints.

So far I can only get it to show the start and end point of a line. Am I doing something wrong? Are curves not fully implemented yet? Just curious how to create a multi-point or bezier curve in Unreal.

Checked both docs and couldn't find much, hopefully not missing something obvious Simple scatterLine otl attached.

Attachments:
ingenuity_scatterLine_0.1.otl (13.1 KB)

Grant Miller
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Ingenuity Studios
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Hello!

When creating a curve input it will create a curve with two control points.

We duplicated how UE4 spline component works. In order to create a new control point, right click on one of the existing input curve control points, and it will bring context menu. There you will have two options, create new point and delete selected. By selecting control point you also will be able to drag it around.

I know, this workflow is not super intuitive and we have received RFEs regarding this. We definitely need to look into improving it.

Thanks and hope this helps!
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Ahh got it, thanks for the reply! I was trying every combination of ctrl + alt + shift I could think of

Adding a point then moving that point hard crashes Unreal at the moment. I have mesh distance fields on for the project, seems like it might be crashing during that step.. Regardless at least I know how it's supposed to work now
Grant Miller
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Ingenuity Studios
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Could you give me reproduction steps for this? I tried your asset and it seems to work fine.
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For sure:

1. Import the digital asset
2. Set inputs > line to curve input
3. Set inputs > object to an imported fbx (I used the attached sphere)
4. Move one point on the curve
5. Right click the point, add point
6. Move the newly added point
7. Unreal Engine hard crashes

Windows, Unreal Engine 4.7.6, Houdini 14.0.361
Grant Miller
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Ingenuity Studios
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I am not sure I can reproduce it, perhaps I am still doing something wrong.
Edited by - June 11, 2015 12:51:55
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Ah, so it is mesh distance fields. Apologies, I missed that crucial step (they were already on in my scene). I can confirm that it doesn't crash when they're not on, though they're needed for raytraced shadows.

To enable mesh distance fields:
1. Open Project Settings (settings dropdown)
2. Under Engine>Rendering > Lighting check “Generate Mesh Distance Fields”
3. Restart the editor
4. Execute the steps in my previous post.

Quick crash video attached.

Attachments:
houdiniEngine_lineCrash.mp4 (2.4 MB)

Grant Miller
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Ingenuity Studios
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Nod I don't think I've ever encountered that, could be caused by us. Can you please file a bug with us for this? So I can track this and schedule this work? Thank you!
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Done and done, thanks for looking into it
Grant Miller
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Hi, I don't seem to have the crash, but how do I feed a curve I created in UE4 (in a HDA under Houdini Inputs) into an input paramater (on the same HDA)?
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