problem rendering 500k+ particle instances in vray 3.4 for maya

[ALFRED_ST_MEDIA]

win 7 pro
maya 2015 ext1 sp6
vray 3.45.01, revision 27093 from Dec 9, 2016

I'm using Soup tools to scatter points on a surface, which will be covered in fruit and veggies (a 20 foot pile of them, in fact). The source geo for the instances are vray proxies. If I create a 40^3 cube of fruit, using the 'instance' command, the 'compiling geometry' phase is quick. If I create a particle grid to create the same amount of delicious fruit and veggies, using maya's particle instancer, the compiling geometry phase takes over an hour on a 32 core dual xeon machine with 191GB of RAM (yeah, I know, odd number, but thats all this system will recognize).

Here's the rub....This is the low rez version. The working version will have over 2M instances. What is the difference between using maya's particle instancer with maya proxies and using the 'instance' copy command? Why is one working sooooo much better than the other?

TIA,

-ctj

[Morbid Angel]

Hey, I'm not sure why the other is faster. But I can suggest try using vray scatter. Its a bit crude but it gets the job done and works well for speed.

[ALFRED_ST_MEDIA]

VRay scatter eh? haven't used it before. I'll give it a shot. Thanks Dmitry.

The reason copy-instance is fast is because vray postpones loading the instances as geo, since they are instances of vray proxies, and I'm sure I'll be corrected on this, but the only thing written to the vrscene file for render time is the transform info. The geo is already a vrmesh (or alembic, wrapped snuggly in a vray proxy node), and doesn't get loaded into the scene until actual render time. It would appear the other method, particle instances, are being treated as actual geo, and getting converted while building the vrscene file...which takes a while.

[vlado]

Here's the rub....This is the low rez version. The working version will have over 2M instances. What is the difference between using maya's particle instancer with maya proxies and using the 'instance' copy command? Why is one working sooooo much better than the other?

There shouldn't be such a big difference. Can you give us a scene or some more detailed reproduction steps?

Best regards,
Vlado

[ALFRED_ST_MEDIA]

attached are two files, and the vrmeshes they point to. One has copy instances, and the other uses the particle instancer.

Looking forward to seeing what you think.

Thank you,

-ctj

[Morbid Angel]

vray scatter though not free, gets the job done well enough. Its also tied with vray better. Soup has some issues with velocity, I had cases where velocity was totally borked from soup particle. Its last thing you want to deal with mid project where everything is already setup.

If your objects don't have to move and just be static, it should do the job well.

[ALFRED_ST_MEDIA]

vray scatter though not free, gets the job done well enough. Its also tied with vray better. Soup has some issues with velocity, I had cases where velocity was totally borked from soup particle. Its last thing you want to deal with mid project where everything is already setup.

If your objects don't have to move and just be static, it should do the job well.

VrayScatter is wonderful! And they are super helpful as well. I remember now we looked at vrayscatter a while ago but didn't like their licensing (node locked, and pay for render nodes). They have floating licenses now and renders just fine.

Thanks for the recommend.

[yolov]

It translates and compiles geometry on a i7 for about 20-25 seconds here. I'll give it a go on a multi-core xeon next week.
I've only tried the grid scene, the other one relies on references maya files that contain the geometry - can you include them, so we can test the other scene too?

[ALFRED_ST_MEDIA]

It translates and compiles geometry on a i7 for about 20-25 seconds here. I'll give it a go on a multi-core xeon next week.
I've only tried the grid scene, the other one relies on references maya files that contain the geometry - can you include them, so we can test the other scene too?

ah, sorry. I'll get to that today. Yes, the one using maya.cmds.instance() to populate the scene renders quickly. The one relying on the particle 'instance' node takes a much, much, much longer time. I'll correct the example and re-upload later today.