halfExtent
A location marking the end of the field’s area of effect.
Declaration
var halfExtent: SCNVector3 { get set }Discussion
To define a field’s area of effect, use the position property of the node that contains the field and the field’s halfExtent property. The center of the area of effect is the node’s position. The half-extent, a position vector in the local coordinate space of the node containing the field, marks one corner of a box, and the negative of the half-extent vector marks the opposite corner of the box. For example, if a node’s position is the vector {2.0, 2.0, 2.0} and it contains a physics field whose half-extent is the vector {0.5, 0.5, 0.5}, the field’s area of effect is the box extending from 1.5 to 2.5 along each axis of the scene’s coordinate system.
By default, a field’s area of effect is the interior of this box shape. Use the usesEllipsoidalExtent property to instead make the area of effect an ellipsoid bounded by this box. Use the scope property to choose whether the area of effect is the interior or exterior of the box (or ellipsoid).
The default half-extent is the vector {INFINITY, INFINITY, INFINITY}, specifying that the field affects bodies located anywhere in the scene.