This is the place where the simulation preferences are defined.
The "Solver" tab is subdivided into two sections:
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Imagine an animated object falling into a container with calm water.
Here, RealFlow | Cinema 4D uses very large substeps to speed up the simulation.
Due to these large steps the interaction between the object and the fluid is delayed.
With “Use Geometry Velocity” the interaction will happen in time again.
Maximum Deformation Allowed
This is the threshold used to consider if an object with a RFCollider is being deformed or just transformed. A bigger value would recompute less often the colliding geometry, thus providing a better performance. However, if the value is too high there might appear differences between the real object and the geometry "seen" by RealFlow. If the value is too small, some objects that are just animated (or parented) may be considered deformed just because of precision errors, decreasing the simulation performance greatly.
The value represents a percentage of the distance between every vertex and the center of mass of every object. The default value of 0.5% should work for most parented objects.
Auto Params
When enabled, RealFlow | Cinema 4D applies default settings. These default values work for most projects with PDB or SPH fluids, but for other materials (granular, viscous, etc.) it is normally necessary to apply custom settings. This also applies to simulations with collision geometry involved.
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