APEX and Invocation of rig graphs

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I'm working on getting a better understanding of APEX; my aim is to create a simple rig where a sop geometry is controlled by one transform object. I got it to work without using the invoke graph SOP, but when I try to use the invoke sop, I don't understand how to make it treat the APEX graph as a rig graph so that the transform controls show up in the animate state.

Because this is so simple, there should be no need to set up any type of kinefx skel and the only thing I really need from SOPS is the geo(shp). In the file provided (the not working red section), essentially I want a better understanding of how to use such a setup to create the packed shape and rig prims and get them to be picked up by the animation state and when does houdini treat the APEX graph as a rig graph?

Hopefully that all makes sense.

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simple_apex_test.hiplc (150.9 KB)

hou.f*ckatdskmaya().forever()
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I'm unsure of what you're trying to accomplish using the invoke graph here, but what I can tell is that there simply no 'rig' to execute in your scene animate, you pack a box using the packfolder node and call it base.rig, but it still just an inert cube, there no graph to be executed by the scene animate.

when you use invoke sop, the graph you're inputing in the first input is what gonna be executed at this very moment, what the invoke will output in your case is nothing more than the geometry you packed. the graph itself you used in the invoke do not carry over to the next step.
Edited by Jacquesf - 2024年3月11日 04:32:19
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Jacquesf
I'm unsure of what you're trying to accomplish using the invoke graph here, but what I can tell is that there simply no 'rig' to execute in your scene animate, you pack a box using the packfolder node and call it base.rig, but it still just an inert cube, there no graph to be executed by the scene animate.

when you use invoke sop, the graph you're inputing in the first input is what gonna be executed at this very moment, what the invoke will output in your case is nothing more than the geometry you packed. the graph itself you used in the invoke do not carry over to the next step.

Thanks @Jacquesf, is there a way to have the invoke send out a rig graph?
hou.f*ckatdskmaya().forever()
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The difference with APEX compared with traditional Object-based rigging is that a lot of structure that was sort of black box before is now explicit. So it's more low-level. However, for simple cases like this, we have built up some utilities to do it in the context of an APEX "Scene" like the APEX Scene Add Prop SOP (see attached).

You don't really want to use the APEX Invoke Graph SOP directly since it is a lower-level building block.

Attachments:
simple_apex_test_simpler.hiplc (212.9 KB)

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traileverse
essentially I want a better understanding of how to use such a setup to create the packed shape and rig prims and get them to be picked up by the animation state and when does houdini treat the APEX graph as a rig graph?

It's done by naming. The "Foo.char" folder is treated like a character, and then the .rig inside is treated as a rig. The .rig's graph inputs gives the names that it needs from the other character elements.
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PS. For future APEX rigging questions, please use the Rigging forum [www.sidefx.com].
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