1. A navigation system, comprising: an image sensor operable to obtain range data for a first scene; and a processing unit coupled to the image sensor and operable to identify one or more plane features, based on the range data, using each of a plurality of scales; wherein the processing unit is further operable to combine each of the one or more plane features with a corresponding plane feature from each of the plurality of scales and to project the one or more combined plane features to a reference orientation.