---
title: "Liquid Resimulation"
canonical: "https://documentation.chaos.com/space/PHX4MAX/124662754/Liquid%20Resimulation"
format: markdown
---
This page provides information on the Resimulation rollout for a LiquidSim object.

## **Overview**

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Liquid Resimulation uses an already simulated cache sequence and allows you to add, delete or modify the Splash, Mist, Foam or Wetmap particle systems. It will preserve the Liquid and the particle systems you are happy with.

The particle resimulation will affect only the particle systems which are checked in this rollout. If a particle system is not checked, it will remain unchanged. The Liquid always remains unchanged. While the [Fire/Smoke Resimulation](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/125312243) by default creates new cache files during the simulation process, the Liquid Resimulation overwrites the existing cache files.

Using Resimulation to just modify a particle system is practical only in case you have a large number of secondary particles such as Foam, Splash, etc. in relation to the number of Liquid particles. Otherwise, if you have mostly Liquid particles and very few other particles, it will be faster to just simulate over again.

Additionally, the scene must be intact between running the base simulation and the resimulation. Please do not remove any Sources and their emitters, obstacles or forces that interact with the simulation.

Select **Resimulation → Particle Resimulation → Enable** and select the respective particle system below (i.e. Splash and Mist, Foam or Wetting).

![image]()

Modify the particle system's settings - e.g. for Foam, go to the [Foam](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/124531048) rollout and tweak the parameters there.

![image](media://7a94695c-8fe8-47fe-97f2-8dbc00775fcc)

Hit **Start** to run the simulation again - repeat this process until you are happy with the result.

![image](media://f06809d3-7ad0-44ca-b74c-231fd8b47a26)

Select **Resimulation → Particle Resimulation → Enable** and select the respective particle system below (i.e. Splash and Mist, Foam or Wetting).

![image]()

Make sure the particle system's simulation is *Enabled*, e.g. for Foam open the [Foam](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/124531048) rollout → select the **Enable **option.

![image](media://3e9bb34e-b2b0-43dd-8cf5-41a657199e2b)

Hit **Start** to run the simulation again - the particle system will be added to the cache sequence.

![image](media://f06809d3-7ad0-44ca-b74c-231fd8b47a26)

Select **Resimulation → Particle Resimulation → Enable** and select the respective particle system below (i.e. Splash and Mist, Foam or Wetting).

![image]()

Make sure the particle system's simulation is *Disabled*, e.g. for Foam open the [Foam](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/124531048) rollout → deselect the **Enable **option.

![image](media://a6892c41-038c-4558-984f-f9f3a69d38a7)

Hit **Start** to run the simulation again - the particle system will be removed from the cache sequence.

![image](media://f06809d3-7ad0-44ca-b74c-231fd8b47a26)

> Macro (ui-text-box)
> 
> UI Path: ||Select [Liquid Simulator](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/125052235) object|| **> Modify panel > Resimulation rollout**

##   
**Parameters**

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### **Particle Resimulation**

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### **Resimulation Cache**

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> Macro (ui-text-box)
> 
> During resimulation, Phoenix reads cache files from the Base Cache Files Path, performs resimulation operations, and then saves a new cache sequence in the Output and Render Path.
> 
> For more information on how to set up resimulation paths, see the [Tips and Tricks page](https://docs-chaos.atlassian.net/wiki/spaces/PHX4MAX/pages/125311346/Tips+and+Tricks#ResimPaths).

> Macro (ui-text-box)
> 
> You can use the same Output and Render Path as the Base Cache Files Path, and this way Phoenix will not create a separate cache sequence for resimulation, but will overwrite the base simulation caches instead. It's valid to do so if you need a more complicated setup or when not enough disk space is available.

> Macro (ui-text-box)
> 
> The following error message may appear when you start a re-simulation:
> 
> "Cannot start the Re-Simulation! Please make sure the simulation was run with the 'Velocity' channel checked under the 'Output' rollout, and that the cache files in the Simulation Input path exist."
> 
> The reason may be that either the files in the Input Simulation Path do not exist at all, or they do not have Grid Velocity Channel exported when you have simulated them beforehand. Of course, you may use more complicated setups where you resimulate over an already resimulated cache file, or you may Load an existing base cache file as the initial state of the re-simulation. These are all possible; you just need to have velocity in the base cache and an existing path to it.