This is an area emitter. An arrow indicates the node’s emission direction and helps you to point the emitter to a certain target. You can position (W key), rotate (E), and scale (R) this emitter.
Emitter Type
If you want to Toggle the emitter's type with this drop-down menu. The following parameters and the viewport representation will be updated according to your selection. Bear in mind that type changes will change the emitter's shape choose an appropriate entry from the menuand fluid's behaviour completely.
Volume
This feature creates a defined volume of particles. The size of this volume is defined by the emitter’s horizontal → “Scale” settings and the vertical value entered here. All dimensions are given in metres. By activating this option, the emitter’s speed value will be set to 0.0 automatically.
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