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.
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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