copy method
Implementation
@override
copy(Object3D source, [bool? recursive]) {
super.copy(source);
// if ( source.background !== null ) this.background = source.background.clone();
// if ( source.environment !== null ) this.environment = source.environment.clone();
// if ( source.fog !== null ) this.fog = source.fog.clone();
// if ( source.overrideMaterial !== null ) this.overrideMaterial = source.overrideMaterial.clone();
// this.autoUpdate = source.autoUpdate;
// this.matrixAutoUpdate = source.matrixAutoUpdate;
return this;
}