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RealFlow | Cinema 4D's simulation files can become very large, and this is often seen as something negative. But, the information for 1 or 2 millions of particles have to be saved somewhere. That's a simple fact. Unfortunately, we're not able to magic away all the position, speed, or density data 
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- Go to Scene > Cache and specify a folder where the files will be stored.
- Click on "Create Cache Simulation"; a progress bar appears.
- Once the simulation is finished, the "Use Cache" checkbox will be enabled and you can scrub the timeline to see the results.
- The simulation can be interrupted at any time with "Cancel". With heavy simulations it might take a few moments until the simulation will be aborted.
- Press "Remove Cache" to delete the cache folder's content. You have to confirm this action.
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