In order to create a fluid volume it is always necessary to attach an object to a HyFLIP emitter. You can use any object and tag it as a fluid source. This combination – emitter and object – defines the point of emission.
Working with Multiple Emitters
If you want to render different emitters separately you have to activate each emitter's export resources under:
Export Central > Hybrido Emitters
There, check the emitter nodes you want to export and RealFlow will write the particle data to the according files. These files can then be read by the → RealFlow RenderKit or the → connectivity plugins. If you activate the Alembic format you do not need any plugins:
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This is the parameter reference for the Hybrido emitter.