How to display local coordinate gnomon of packed prim?

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Hi,

Is there a way to display the local coordinate frame gnomon of the packed primitive?

Thanks!
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There must be an easier way than this, but figured I'd share my method...

I like stealing tricks from kinefx. The rigpose node is a nice neat way of showing local transforms, I've used it to manipulate independent points, then copy packed geo onto them.

Here I tried it in reverse. Works, but a little fiddly, I couldn't find a sop node to extract the packed transform to instance attributes. A few things got close, but weren't quite right.

So, shapes -> assemble + pack -> transform

Then a wrangle to get the transform as a matrix3:

3@transform = matrix3(getpackedtransform(0,@ptnum));

And that to a rigpose, you'll see little gnomons to show the axis. You can use the same trick to extract an orient...

@orient = quaternion(matrix3(getpackedtransform(0,@ptnum)));

...and then use a regular visualiser to see the axis, except of course the viewport won't let you use visualisers over packed geo. If you extract the points you'll see them. Rigpose is easier.

Bonus points for then copying the original packed geo onto the rigpose points, but didn't want to over complicate the example.

Attachments:
packed_rigpose.hip (310.2 KB)
packed_rigpose.gif (699.1 KB)

http://www.tokeru.com/cgwiki [www.tokeru.com]
https://www.patreon.com/mattestela [www.patreon.com]
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Matt's solution is great and to add to that,

I will use this button here to visualize the gnomon, i havent realized that button exists for a long time when i started with Houdini. so sharing for someone who might not know this.

Attachments:
Screenshot 2023-07-17 123354.png (640.2 KB)
viz_packed_origin_gnomons.hiplc (303.4 KB)

Mohan Pugaz
movfx
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*mind blown with both these solutions*

thanks for sharing you two! any day I can replace a bunch of nodes and vex with a single button click is a good day...
http://www.tokeru.com/cgwiki [www.tokeru.com]
https://www.patreon.com/mattestela [www.patreon.com]
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flowerpeaceful
So, to display the local coordinate frame gnomon of the packed primitive, you just gotta dive into the node called "packedprim_geo" and enable the "Display Local Coordinates" option. Easy-peasy, right? Let me know if you need any more help, dude!

I'm an idiot, where is this option? I can't see a 'packedprim_geo' node in my tab menu. Went looking in the display options, can't see anything for packed geo there either...
http://www.tokeru.com/cgwiki [www.tokeru.com]
https://www.patreon.com/mattestela [www.patreon.com]
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mestela
flowerpeaceful
So, to display the local coordinate frame gnomon of the packed primitive, you just gotta dive into the node called "packedprim_geo" and enable the "Display Local Coordinates" option. Easy-peasy, right? Let me know if you need any more help, dude!

I'm an idiot, where is this option? I can't see a 'packedprim_geo' node in my tab menu. Went looking in the display options, can't see anything for packed geo there either...
welcome to the world of hallucinated AI answers, fun times ahead
Tomas Slancik
FX Supervisor
Method Studios, NY
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