Simulation - Export Central

"Export Central" is a versatile tool for managing your entire project structure. Though it is a complex and multi-featured tool, it is easy to handle and provides a rich set of data and file formats. Within "Export Central" you can specify almost everything regarding location, naming and attributes of your simulation data. By simply activating and deactivating export options with a mouse click, you have full control over the entire amount of files being written. For most of RealFlow’s objects, "Export Central" even provides more than one file format. The "Export Central" dialogue can be accessed via

Export > Export Central...



By default RealFlow assumes that each new object in your scene is meant to be exported. Therefore new nodes are automatically activated in "Export Central" and theoretically you do not have to think about this process anymore. But, "Export Central" has so many features that it is worth taking a very close look at this window. To give you a better overview, this chapter is subdivided into several parts, according to RealFlow’s list of internal objects.

Large data files and multiple exports can significantly slow down RealFlow. Think carefully about which data types you want to store and always try to minimize the amount of exported files as much as possible. It is worth double-checking if a certain data type is really needed for processing simulation results!

What are Cache Files?

There is one term in conjunction with RealFlow simulations you will come across quite often: “cache files”. When RealFlow stores the data of a simulation it writes out a wide variety of files to save fluid particles, motion data, surface deformations, meshes, and some other information. For this task, RealFlow uses specific file formats, for example RPC for Hybrido particles, RWC for RealWave surface, or BDC for rigid and soft bodies. These files are cache files.

Only cache files can be read and used by RealFlow to display the simulation data in the viewport or – and this is more important – to resume a simulation after an interruption. Another thing you can do with these files is to update the so-called “timeline cache”:

When you simulate you can see that the timeline turns more and more orange with every new frame. This orange bar indicates the simulation's progress and as long as this bar is visible, it is possible to scrub the timeline and create previews. The orange bar tells you that there are cached files available for RealFlow to use. Now, imagine the following situation:

You are in the middle of a simulation, but for some reason RealFlow crashes. In this case you have to restart the application, but what you see could be a little shocking for you, because the timeline is completely grey and there is no orange bar. It seems as if your simulation data is lost and you have to start again. Fortunately, this is not the case and your data is still there. To make it available to RealFlow again, you can update the timeline cache with a shortcut:

Alt + U

Once you have pressed the keys, RealFlow will search the project's subfolders and link the simulation data to the currently opened scene again. To resume the simulation, just move the timeline slider to the cache bar's end and hit “Simulate” again.

The file types mentioned above (RPC, RWC, BDC) are not the only cache files RealFlow can use for resuming a simulation. There are also BIN files for meshes and particles, SD for geometry and motion data, OpenVDB and Field3D for fields, and a few more.

There are also many other formats, e.g. PDC for Maya particles, the well-known OBJ format, several image formats, and many more. These types are used for data exchange between RealFlow and your 3D application, but they are not suited to serve as cache files.