set instance geometry and bifrostgeotomaya

[Anonymous]

is there a way to connect a set instance geometry nodes output to a bifrostgeotomaya node? i wish to render particle instances in redshift

[syracoj]

no there is not.

you would have to create an object replicator graph (which will place copies (not instances) of your input object at point locations) then connect that to the BifrostGeoToMaya node. Obviously you will lose out on performance and interaction benefits that instances offer.

[Anonymous]

do you mind explaining how i would do that?  i would forever be greatful 😆

[syracoj]

see attached video

[Anonymous]

This looks like exactly what I need, however I need to get it working with mpm simulation rather than particles. How would I go about doing that?

Many thanks!

[syracoj]

what kind of MPM simulation? MPM points (like from snow and sand)?

[Anonymous]

Exactly yeah, from a source_mpm_sand node plugged into a simulate_mpm node in this case.

[syracoj]

so the simulate_mpm node outputs an array of data. You can plug a first_in_array node after this and then use get_point_position compound to get the point positions of the mpm sand points. From there you should be able to use those point pos to replicate or instance objects onto.

[Anonymous]

That's got it! Many thanks Syracoj!

[andrea_pinto82]

If you use only position.

You can use a construct mesh from granular particles and use bifrostGeoToMaya to convert in maya mesh.

Then create a particle system with goal object.

Then create your instancer.

[andrea_pinto82]

Or you can make an arrayMapper plugin with python and connect bifrost to particles.

[lee_bowitz]

Hello i am also trying to get this too work but get confused with the first array onward.. could u help me out a little..  i tried all day to get it to work and failed..

[forrest.brent]

@andrea_pinto82Any chance I could have a gander at your custom plugin code?  I've been tasked with writing something similar and I'm quite new at the OpenMaya API

[andrea_pinto82]

Ciao, sorry for reply late. I hope this will be useful. 

Let me know.

[bugsdabunny]

Hey @andrea_pinto82 I'm having a bit of trouble getting it to work. I got the plug-in loaded but I'm not sure how you are connecting it to the input Array Point on arrayMapperCustom from Bifrost output point_posistion1. The data types don't seem compatible. Also I see a for_each bifrost node doing something to the point_positions, but I can't see what is being done. 

I don't know much about nParticles node in Maya, where are you connecting the input geometry, like the cubes in your video? And which input is count connected to? Is it called max_count on nParticles shape? Thanks for any help!

[bugsdabunny]

Hey @andrea_pinto82 I was able to get some of it working, but not quite everything. In your video you have it dynamically changing the amount of total particles. How are you connecting it in the node editor? When I try I have to connect them all individually one by one... 

[andrea_pinto82]

https://vimeo.com/570404303

https://www.youtube.com/watch?v=occxHiAzPKQ

I speeded up the video

Let me know 🙂

ciao

[bugsdabunny]

Hi @andrea_pinto82, thanks so much for the video, it clears up a lot of things. The part that is not working for me is the part where you connect the whole Point Position array in the node editor, to your arrayMapperCustom node. In the node editor I cannot connect the whole attribute, just each one, one by one. I am not sure why yours will let you? Is it a special setting? When I click the top level plug then it just expands, doesn't let me connect, only one by one

It is at 1:30 in the youtube video https://youtu.be/occxHiAzPKQ?t=90

[andrea_pinto82]

I found your issue in maya 2020,  maya 2022 is different.

Try this scene.

let me know 🙂

[bugsdabunny]

Perfect! It works, thanks so much, this is a game changer!