dopimport y=0 is not y=0

[Follyx]

wired:

working on a big destruction file. And always got another result as I assume. So made this tiny file to check the similiar steps one after another and found following:

After importing the small cube with y and ty = 0 into dops it isnt 0 anymore. Only after 50 frames it level near 0. But not 0. only with a checked "compute mass" and density NOT 0, y=0. As soon as I change the density, the y component change. Why is this?

Looks like the atoms have come to rest... ;-). But seriously, is this wanted, an if so, why?

gluetest_2_objects.hip

Edited June 29, 2020 by Follyx

[anim]

5 hours ago, Follyx said:

only with a checked "compute mass" and density NOT 0, y=0.

it's strange what you are saying, since it should be the opposite and also your file behaves the opposite, only with density 0 or mass 0, y should stay at 0, since there is no forces applied to it 

as soon as it has mass, it will be pulled down by gravity and collide with ground, and please don't expect object settled on the ground to be mathematicaly precisely settled without any error, 1e-5 sounds pretty tolerable

the bigger difference on the first frame, is simply because your geo has Solve On Creation Frame checked, while Ground doesn't, so there is no ground colliding on the first frame and your cube sinks a little bit lower which for the next few frames will recover from

 

[Follyx]

Fantastic Thomas, thank you. The checked Solve On Creation Frame makes sense and is currently enough for my "under the hood" knowledge.

I really missed to check if its active on both. Ground and box.

Edited June 29, 2020 by Follyx

[anim]

31 minutes ago, Follyx said:

I really missed to check if its active on both. Ground and box.

well, Ground doesn't have it promoted so it wouldn't be obvious at first that it behaves that way, but to sync them

you either uncheck the one on your rbd object

or unlock Ground and check it on emptyobject1 node inside