Volume
Tip:Note also the Polygon Field Layer. You can drag Volumes directly into a Field list where it will be placed as a Point Object Layer and will offer even more possibilities than the Volume Effector.
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This Effector defines its range of influence based on spatial polygonal objects (Primitives not made editable can also be used). All Clones that lie within a given object’s volume will be influenced by this Effector. Make sure the volume used is a closed volume. Otherwise unexpected or unwanted results may occur.