Hi,

I am currently building a larger hda, but ran into an issue when I am trying to do some geometry processing and python is called.

I first noticed it with the group_expression sop.
I am able to load the hda in Maya 2018.3, Houdini Version 18.0.377, Houdini engine version: 3.3 (API: 2).
But as soon as I included the group_expression sop, the asset would throw an error:

// Error: Object (ID: 0): /obj/test_engine_simple1 Geo (ID: 14): /obj/test_engine_simple1/geo_OUT/output0 No geometry generated! //

Also the very first time I load the asset I get:
// Error: HAPI Error: Error setting kwargs: Traceback (most recent call last): File "opdef:/Sop/groupexpression?PythonModule", line 1, in NameError: name 'hou' is not defined

So I looked around a bit and this seems to happen when:
is not added to a python script.

The group expression sop internally seems to be doing some python script, so that is probably why it fails.

I then tried it with a python sop to confirm that this is the issue. I picked the preset to ‘move points up’ and at the beginning of that blurp of code I added:

But that did not help.
So now I'm thinking that houdini engine is unable to find ‘hou’. So that would mean that there is something wrong in the configuration of my Houdini engine installation.

Any advice to help find out where this is going wrong? I'm on Windows 10.

I have attached my simple test otl.
It requires an polygonal input (like a poly sphere) as an input.
- it will subdivide it
- it will rotate it around centroid
- it will try to move the points with a python sop (this is where the asset fails in Maya)


Thank you!
Peter

I've updated my Maya to 2018.6 and Houdini to h18.0.416.
But unfortunately the error remains. (and is tricky to debug. )

Hi Peter, I was unable to reproduce the issue on Linux. I'll take a closer look on a Windows build and get back to you.

Thanks for looking into it.
It's looking more like there is something else going on with the Maya environment that is causing a library conflict.
I'm going to try to use the debugger today to see if that provides any info to help figure out what path or library might be causing this.

Hi Peter, I'm still unable to reproduce the issue in Maya 2018.6 on Windows 10. How have you installed the plugin? After you have updated to 18.0.416, what is the reported Houdini and Engine version within the Maya plugin's preferences window?

Hi John,

After some further debugging, it has to do with the environment within Maya that is being set.
A clean Maya works. So now we're trying to find out what part of our Maya userSetup.py is breaking the houdini engine.

The Houdini engine is v3.3 (API 3). The plugin was installed with the installer.

Also I was unable to run the Debugger -> View Assets in Houdini.
It tries to load houdini fx, but spits out lots of errors in the console. ( within our environment ).
I'll report back if I can and when I know what has caused this.

And with the clean version of Maya, is it loading the plugin from the same location?

With the clean version of Maya it is loading the plug in from the same location.
Still figuring out the other part.

Hi,
any update on this?

I have a hda in maya that doesnt cook on the first load but needs a “reload asset” to make it cook.

I get this on the first load:
// Error: HAPI Error: Error running event handler:
Traceback (most recent call last):
File “opdef:/Sop/hairclump::2.0?PythonModule”, line 2, in <module>
NameError: name ‘hou’ is not defined

I also have the same problem with debugging/viewAssetInHoudini

Maya 2018.6 Win
# Houdini version: 18.0.348
# Houdini Engine version: 3.3 (API: 2)

Thanks!
Kustaa

Hi Kustaa,

Could you please attach the HDA in question? If you don't want to attach it here, please file a bug report.