Simulation issue with objects further from scene origin

 
 
 
Posted by:adamwalkerfilm
Data created:9 July 2018

Hi all,

Working on a large lucid scene and I noticed strange behaviour the further away from the world origin an object was when you have high sub-steps/iterations.

I have attached a test scene and previews illustrating this peculiarity.

The test scene contains three identical splines each with a lucid modifier applied but positioned out from the world origin. If I set sub-steps to 30, Iterations to 10 all 3 yield similiar simulation results, but if I increase to say 100/50 the objects further out become erratic.

If someone can shed some light as to why this is, as my more complex scene requires the higher steps/iterations. My only other thought is to sim each object at the world origin then move them to their respective positions post record simulation.

I am using 3ds max 2017 with Lucid Build 1.4.4.14731

 


Attached Files:

>04_24m_steps30-10.avi (7238144 bytes), >05_24m_steps100-50.avi (7216128 bytes), >Lucid Step Size Problem.max (684032 bytes),

The below post suggests that large sub-steps can become problematic causing precision problems, but does not explain why I'm only seeing this erratic behavior with lucid objects far from the scene world origin.

https://ephere.com/plugins/autodesk/max/lucid/forums/general/thread_4638.html

Hi Adam,

Sorry for the delay. I'm unable to reproduce your video. For some reason my video player is crashing when I load your videos. Can you please upload them to Youtube?

Jeordanis Figuereo (Social Media Manager, Product Designer. EPHERE Inc.)

Hi Jeordanis,

See if this video will play.


Attached Files:

>spline erratic test.avi (11936256 bytes),

Hi Adam,

Just to let you know that we are looking into this. I will get back to you soon.

Jeordanis Figuereo (Social Media Manager, Product Designer. EPHERE Inc.)

Hi Adam,

The team has determined that this is a limitation with nVidia Flex which Lucid is based on. The team suggest using less sub-steps since you have 5000 iterations per frame on your scene, they conside it to be too much.

Also, make sure to place the splines so their bounding box is centered at the (0, 0, 0).

Jeordanis Figuereo (Social Media Manager, Product Designer. EPHERE Inc.)