Output Mesh Vertex Count

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I've been using Houdini and Houdini Engine for Unity for a few months now and I always thought the vertex count is a bit higher than it should be. To get to the bottom of this I created a simple OTL that outputs an input mesh.


After importing the mesh in Maya for further inspection, it seems that Houdini Engine does not weld any verts together even if they share the same attributes. You can see that each triangle is surrounded by a mesh border. Is there any way to go around this?
Edited by spaceapegames - May 4, 2018 13:17:27

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Vertex-Count.jpg (87.0 KB)

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Uncheck Split Points by Vertex Attributes in Houdini Settings window in Unity. And vertex count in Houdini generated mesh become equal unity mesh. But then you need use point attributes except vertex.

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That Split Points by Vertex Attributes is only available in version 1 of the plugin. Version 2 will always split vertices. The decision for this was to reduce issues when marshaling attribute data back and forth between Houdini and Unity.
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Thank you for the reply! Using Version 1 of the Houdini Engine with “Split Point by Vertex Attributes” seems to output a vert count closer to Unity and solves the issue completely.

We are working on mobile games and keeping an eye on vertex counts is quite important for performance. It would be a shame if we have to stick to v1 when v2 goes out of beta. Is there any chance of having this as an option for Version 2 in the future? Or maybe have a “vertex count reduce” post step when baking the mesh.
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I understand your concern. I'll add an RFE to investigate the possibility of perhaps strictly using points, instead of vertices, or another similar method to reduce the overhead. This probably won't happen for a while though.
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Thank you for looking into this seelanv. I really like the new Houdini Engine and looking forward to the option of using points instead of verts.

In the meantime, I implemented a “Weld Vertices” post step after a cook in our project. Not ideal since it's quite slow in Unity but it does give me a significant reduction in vert count without affecting the look of the geometry.


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Available in today's build (16.5.475) is the option to use points instead of vertices.

Also added LOD Groups as well: https://www.sidefx.com/docs/unity/_meshes.html#Meshes_Output_LOD [www.sidefx.com]

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Thank you so much for addressing this so quickly. Can't wait to try this out.
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