copy method
Implementation
@override
PerspectiveCamera copy(Object3D source, [bool? recursive]) {
super.copy(source, recursive);
PerspectiveCamera source1 = source as PerspectiveCamera;
fov = source1.fov;
zoom = source1.zoom;
near = source1.near;
far = source1.far;
focus = source1.focus;
aspect = source1.aspect;
view = source1.view == null ? null : json.decode(json.encode(source1.view));
filmGauge = source1.filmGauge;
filmOffset = source1.filmOffset;
return this;
}