Summary

Title:Particles Explode BUG
Category:Crash/Critical
Status:Open
Posted By:coilbook ( )
Date Created:7 January 2016

Problem

Description:

I think I finally figured out why particles explode. 

Image 1 is when simulation works properly and image 2 is when particles jsut start exploding 

If you change resolution to around 80  and then max particles to 1900000  after that particles will be very slow and will beging exploding. Even if you reduce resolution back to 40.  The only solution is to restart 3ds max. 

Steps to Reproduce:

If you change resolution to around 80  and then max particles to 1900000  after that particles will be very slow and will beging exploding. Even if you reduce resolution back to 40.  The only solution is to restart 3ds max. 

 

Attached Files:
Image 1Image 2

max file 


Attached Files:

>2015+water+glass.max (16961536 bytes),

Also animating solid objects is about 10 times slower than liquid or inflatables 

When rigid is animated it shows particles around 300000 when inflated it shows only 1692 particles 

Thank you for the scene, I will investigate it. Regarding rigid vs inflatable, inflatable creates one particle per each vertex of the mesh. Simulating a rigid fills the mesh with particles which are then connected in a lattice, see here for more info:

https://www.ephere.com/plugins/autodesk/max/lucid/docs/1/Lucid_Modifier.html

You can control rigid parameters to make the lattice more sparse and reduce particle count.

Marsel Khadiyev (Software Developer, EPHERE Inc.)

Sorry, I am not quite able to reproduce the problem described. For me particles explode with both tested resolutions (40 and 80). The only fix for me is to change substep count to 4. With this fix scene simulates correctly for both setups (resolution 40 and 80). I think the problem is in Flex itself. Reverting to simple cube lattice does not eliminate explosion. Here is attached scene with some other fixes (lowered adhesion, switch to convex collision objects).


Attached Files:

>1066_2015_water_glass.7z (53611 bytes),

Marsel Khadiyev (Software Developer, EPHERE Inc.)

Thank you

Could you please explain about Sub-steps and iterations Which one should be bigger. is there like a ration 2:1  etc

 

Seems like increasing it sometimes makes it worse than better even though it says bigger values more accurate 

is there like the best number 

Thank you 

In my experience, this happens when you have used setting that produces too many particles for flex so it fails, then lowers the number to an acceptable value > things explode.

If you reduce the settings to very low values and then progressively rise the number of particles again (but not too much), it should go back to normal.

Is the exploding a general problem? I've experienced this a number of times. Usually after changing values while testing out simulations, the exploding will just start ocurring. Sometimes resetting max helps, sometimes not. This seems to be a graphic card/flex issue and often hampers the "Fluid" workflow of Lucid enormously as all simulation attempts afterward fail (explode). Maybe there's a possibility to reset FLEX back into normal functioning without having to restart 3dsmax?

i think it is FLEX limitation/bug. II hope Ephere can email nVidia about it so they can fix flex bugs