resume sumultaion

[MENOZ]

hi.

I'm simulating a falling wall in dops, I tried to write the .sim sequence to disk using ROP_DOP.

I would like to resume the simulation in another moment.

I used a file dop to read the simultaion back, plugged in the rop dop, adjusted the frame range and hit render. but it doesn't work...

how could I resume the simulation? where should I attach the file read to feed the solver and continue the simulation?

[hopbin9]

The file node goes at the bottom, and should be set to automatic.

Houdini is kind of strange with the order of it's nodes. For sims the file node can push data into the sim from the bottom of the tree, but doesn't work right if it's at the top. See the attached image (file-node.jpg)

In most cases, just using an automatic file node at the bottom will work for most cases. It will continue the sim past any frames where the cached files are missing.

Now, if you want to have an exclusive node that only reads from the sim files. Then you can create an independent file node which is set to read (you can have a DOP network with just one read node, and it'll be a valid network). The read nodes output the geometry and object data so they are not dependent upon the source objects. You should set the "Take Ownership of Loaded Objects" flag to true if the read node is loading sim files created from a different DOP network. If you only have one DOP network then this isn't a problem, but when you scene has multiple DOP networks then there can be duplicate names.

[MENOZ]

oh thank you, I will try this way.

So i cannot use the rop dop to esport and resume my sim files?

I thought that using rop dop instead of file dop would be a little faster because It hasn't to show the geometry in wiewport

another problem is that the files are pretty slow when i read them back, i suppose because there is all the sim data and not only the geometry. is there a way to load only the geo just for a preview?

[hopbin9]

The ROP Output driver is used to bake the simulations when using a farm. It allows you to run the sim on hQueue or hBatch, and save the sim files in a folder.

You can then load those sims using the DOP file node in a different Houdini HIP file.

A ROP node will not allow you to resume a simulation, since it's only writing the output.

I've never used the ROP Output driver yet, but it looks like something I would use for batch processing a bunch of sims.

[RontheDon]

Hi Menoz,

I think what you are looking for is the "Explicit Cache", which you can find on your DOP Network-SOP under the simulation Tab.

With this enabled you can continue your simulation where left off even after a complete crash / movie break .

These files are comparitively huge though, so I'd suggest to limit the frames to cache/keep to i.e. 5-10.

hope this helps

cheers

ron

[MENOZ]

Hi Menoz,

I think what you are looking for is the "Explicit Cache", which you can find on your DOP Network-SOP under the simulation Tab.

With this enabled you can continue your simulation where left off even after a complete crash / movie break .

These files are comparitively huge though, so I'd suggest to limit the frames to cache/keep to i.e. 5-10.

hope this helps

cheers

ron

from help:

The explicit cache is similar to using a File DOP in Automatic Mode. However, when you try to jump to frame 50 with a File Dop it must load the first 50 frames. With the explicit cache it can skip this step.

great! but why file Dop must load the previous frames?