The estimated width and length of the detected plane.
- iOS 11.0+
When ARKit first detects a plane, the resulting
ARPlane object has a
center value of
(0,0,0), indicating that the translation portion of the anchor's
transform value locates the plane's center point.
As scene analysis and plane detection continues, ARKit may determine that a previously detected plane anchor is part of a larger real-world surface, increasing the
extent width and length values. The plane's new boundaries may not be symmetric around its initial position, so the
center point changes relative to the anchor's (unchanged)
Although the type of this property is
vector, a plane anchor is always two-dimensional, and is always positioned and sized in only the x and z directions relative to its
transform position. (That is, the y-component of this vector is always zero.)