If I use vertex UVs on export to other programs it turns out that every triangle in the UVs is separated. Most other applications do not a appreciate that. I can clean that up in Maya, but that is not a good workflow.
If I promote the UVs to a point attribute they borders of the UV islands get fused (which is not what I want for obvious reasons).
If I promote the UVs to a point attribute using a vertex split sop, the UV islands stay separate but the geometry gets split apart (and the normals get messed up in the process).
Is there a way to achieve a proper UV export without messing up the geometry?

- I suppose I could transfer the normals from before the split onto the split version, but in a package like Maya such a mesh would have to be considered broken. To further process such a mesh in Maya I would have to unlock the normals (and lose all normal information I defined in Houdini) and merge (fuse) the mesh. Undoing all the work I have done in Houdini.

Note to myself so I won't forget it again: I should promote the Normals (optional) and UVs to vertex and then fuse the points.

Hello DASD ,
I'm looking for a solution in this UV broken issue …Did you find any solution ?

Use vertex UVs, then in Maya you go into the UV editor, select all UVs and use the Merge UVs function. Usually that does the trick.

lternatively you can also select the mesh and use the Mel script command:

polyMergeUV -d 0.01;

Tell me whether this works for you.

Hello ,
Thank you for your answer
I know the first technic (i used to do it with Max)
but i would prefer not to have to open another software
so i will try your script .

(sorry , i just realized you were mentioning script within maya
toobad for me …
it would be great if maybe one day Sidefx add the possibility to do it at export !)
at least for unity or unreal because it's not good for the engine to have too many seams…

It should work the same way in 3Ds Max. I don't have it handy right now, so I cannot check.
https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/3DSMax/files/GUID-9E98AEAC-F06F-4FAD-9091-DCD30AC9BB26-htm.html [knowledge.autodesk.com]
Should be welding with a (small) treshhold.

Yes,
I can confirm it work in 3ds max this way :-)

thank you again for answering

Hi, I have the same issue with using the Houdini engine in Unity.
I can't bake shadows on the mesh that gets generated by the houdini asset in Unity.
Does anybody know a way to fix this in houdini?

arjanM
Hi, I have the same issue with using the Houdini engine in Unity.
I can't bake shadows on the mesh that gets generated by the houdini asset in Unity.
Does anybody know a way to fix this in houdini?

Try checking the Unity Houdini Engine subforum and maybe make a thread there. Or is it solved already? - If your research comes up with nothing make an RFE.

Hi,

Just a quick update on the original issue, but the FBX and OBJ exporter in tomorrow's daily build (16.5.535) will only export unique UV values, which will fix the broken UV borders when exporting geometry from Houdini to those formats.

dpernuit
Hi,

Just a quick update on the original issue, but the FBX and OBJ exporter in tomorrow's daily build (16.5.535) will only export unique UV values, which will fix the broken UV borders when exporting geometry from Houdini to those formats.

- Will this also work for Houdini Engine?