Hello!

I have this vellum grain simulation that is pretty high res, so it takes a bit of time to calculate. What I did was simulate the first 50 frames to get a good rest position for the grains. I set that 50th frame as the initial state for the simulation. Here is where I am unsure. I made some changes to one of the colliders and removed a pop drag node then added a pop force node. Is it ok to make all these changes to the sim? Or should everything match what was in the original simulation? I ask this because I am getting some weird behavior from my pop force node. Even if I turn the amplitude on the turbulence to 99999999 it has almost no effect. If I clear the initial state and use the pop force node, I do not notice the same behavior. In summary, when you use an initial state for your simulation, should you have the same data before and after you set the initial state?

Hi

It's depend to what change you want to do after cache, Usually this problem is happening when you add new dynamic Object in the DOP Networks, e.g Colliers or new RBD Object or Particle and … .

But it should be ok if you want to add or edit new dynamic data (Not Object) such as forces or tweaking velocity via wrangles.
So be careful about changing collision objects after cache.


I think that's because these new dynamic objects are not exist in the Initial State, they need to build in the first frame of simulation, But in this case it's not possible because of Initial State.
But some Data such as forces are exist and by using new force nodes you are just changing these forces data, there is no new dynamic object.


However it is not preferable idea to do such a these changes after caching simulation.

Hey, thanks for the reply. I forgot to post my solution here too (I asked in od forums too).

I think the problem is when I saved my initial state, my pop drag was left at 1000. To fix my problem I just re-attached my pop drag node and set the air resistance to 0. I believe the drag just kept damping everything even though I had disconnected the pop drag node after loading the initial state.

Also, I was able to add a new object that wasn't in the initial state. I just changed the creation frame to frame 2. It can't build on frame 1 because its reading a file. Just switch creation frame for the new object to frame two.

Hello Again !

Great,Thanks for letting me know.

Also changing Start Frame was tricky and that's a good solution, in this case we can build our new object in the simulation.

Thanks,
Sadjad