SubmitConstraints Timestep is Sometimes Zero

[AntonSynytsia]

I've been working on implementing custom joints into my wrapper and I figured that timestep parameter in SubmitConstraints callback doesn't always yields the update timestep. In many cases, occasionally, the timestep parameter is zero. In my implementation, there are cases when I have to divide by timestep and when timestep is zero, dividing by zero may lead to a crash. Is there a reason why the timestep parameter of a custom joint SubmitConstraints function yields zero in some cases? Is that a bug?

[Julio Jerez]

are you using continues collision?
this will happen in continues collision mode.
basically the island move to a by a fraction of time until the moment of collision.
and the movement of collision the impulse forces dominate the all other forces,
this is why you see the a call with a zero time step.
you soul simple return zero no emitting any row or Colum.

what hammed is that at that moment only contact have partial derivat9ibe because ether derivation is a step function, all other joint the derivate is zero.
I a way yes it is a bug because, the solve should skip the call to the joint when this happens.

Please tell me if CCDD that is what you are doing and I will fix it tonight.

[AntonSynytsia]

Yup, zero timestep is when continuous collision is enabled. So, I basically should return without processing when timestep is zero.

[Julio Jerez]

that's the idea, but since that are so many joint that are not obeying the rule, it is better if I control, that form the low level.
I will try to doing tonight and commit, are you using the late version?

if not I can tell you what to make the change

[AntonSynytsia]

I'm using latest version from github along with some customization. You don't have to tell me what to change. Github will show all the changes you commit.

[Julio Jerez]

ok done

[Sweenie]

ok done

Uhm, did you commit the change or am I using github wrong?
The last commit is three months ago.

[Julio Jerez]

I think I did, try again, if no I will check again,
the change tonight, the place I am has very retorted internet access, I can not get GitHub.

[AntonSynytsia]

Nope, the commit is still not showing up at github.

[AntonSynytsia]

If you're using a github app and in case you're not familiar with it and in case it's not the internet issue, there is a sync button on the upper right corner. After you commit the changes, you have to sync them.

[Julio Jerez]

After you commit the changes, you have to sync them

ups I forget the sync options, I do it tonight, sorry.

[AntonSynytsia]

Thanks, its synced now.