I am trying to string HDA processors together but after the first bake or so, the HDAs are not finding each predecessor's output geo, so they are all failing. The processors that require input have the “Create File Inputs” property set.

I have attached a simple repro where I cannot even visualize the output geo from a single HDA processor in my PDG. The file node is asking me to “please specify a geometry file.” I have verified that the HDA does cook and the file is created, and if I replace `@pdg_output` in the File node with a path to a specific geo file, it loads fine.

New to PDG, but the feels like a bug potentially as it only happens most of the time…

Hi there,

Are you able to upload the HDA file as well?

Note that in order for the File node to resolve the @pdg_output expression, you will have to have one of the HDA Processor work items selected, as this expression is evaluated within the context of an individual work item.

Thank you!

Thank you for the very prompt reply Brandon!

Pro tip on the work item selection. It makes sense, if it were based on the Output flag on the node like I assumed, it would try to throw output geo for each task in the processor? I think I am understanding it all a bit better.

There is still something funky about how that attribute is refreshed perhaps? When I select a new task in the PDG, not always does the File node pick up that update until I unselect it and select another node in the graph? It was throwing me a bit, but we answered a lot of other questions along the way!

It should be updated every time that you select a new work item. Potential reasons for it not showing could be that the work item is missing that attribute or the file is missing on disk.

If you send me a .hip file with any required HDAs, I can take a look at the behaviour.

Perhaps one of the things I am experiencing is just something wrong with how I have my HDA setup? I am trying to pass a range of values from a Wedge node to drive a noise offset in my HDA.

Using the hip and HDA attached, I can see in several work items that the HDA is seeing the Wedge node's values correctly, but the mesh displayed in the Scene View does not change.

Hi Bryan,

Everything seems to be working good for me with your setup. I can click through the work items on the HDA Processor and they are updated in the scene view.

The one thing I can think of is that the “Cache Mode” is set to Automatic, which means that if the output file already exists on disk it will cook from cache (the work item cooks instantly and the file on disk is reported as the work item's output). Do you perhaps have some bad results on disk and it's picking up those files? If you manually open the geometry files in gplay do they appear correct? If this is the case, you can avoid this by setting the Cache Mode to “Write Files”.

Brandon thanks for sticking with me! Yeah for some reason the HDA running in the PDG is generating identical .bgeo files, despite their logs saying they were run with different offset values (all attached).

Running the values from the log file through just the HDA (outside the PDG), I do get unique geo.
screenshot of gplay display: https://drive.google.com/open?id=1r1nJ5YzuIAJ4rIhBEFhxrmsC535jC7tz [drive.google.com]

Can you try turning on the “Save Debug .hip File” parameter? This will save out a .hip file for each work item in your PDG Temp directory with the state of the HDA. This should provide more information about what is happening.

I am seeing similar issues with 18.0.311 trying to use PDG with apprentice. Lots of crashes also. Even on basic stuff not using the HDA processor but as basic as cooking a Top geometry import node from step 2 of the city building PDG tut.

Came here after a "Local variable 'pdg_input' not found" message in H 18.5.672. PDG feels unreliable. I thought it had to do with me using VRAY for rendering but I'm not sure at this point. Please shine some light on this!

Got the same problem here. `@pdg_input` is there after "generate nodes", but once cooking it's gone.

Finally I get rid of this by using a extra attribute_create. For reference: https://www.tokeru.com/cgwiki/index.php?title=HoudiniTops#When_pdg_input_and_pdg_output_are_blank [www.tokeru.com]