10. A computer based system for 3D shape retrieval comprising: one or more processors; and a similarity engine, implemented on the one or more processors, configured to: determine a similarity between a query 3D model and one or more 3D models using a composite distance function based on a plurality of features of the query 3D model and corresponding features of the one or more 3D models and to retrieve one or more similar 3D models based on the similarity, wherein a feature distance is computed between the query 3D model and the one or more 3D models for each feature, and the composite distance function is computed as an average of each feature distance or an aggregate of each feature distance according to a pre-determined weighting; compute a second feature distance between the query 3D model and the one or more 3D models for each feature, from a second set of features, associated with the query 3D model and the one or more 3D models; evaluate a second composite distance function using each second feature distance; and re-rank the one or more query 3D models based on results of the evaluated second composite distance function.
10. A computer based system for 3D shape retrieval comprising: one or more processors; and a similarity engine, implemented on the one or more processors, configured to: determine a similarity between a query 3D model and one or more 3D models using a composite distance function based on a plurality of features of the query 3D model and corresponding features of the one or more 3D models and to retrieve one or more similar 3D models based on the similarity, wherein a feature distance is computed between the query 3D model and the one or more 3D models for each feature, and the composite distance function is computed as an average of each feature distance or an aggregate of each feature distance according to a pre-determined weighting; compute a second feature distance between the query 3D model and the one or more 3D models for each feature, from a second set of features, associated with the query 3D model and the one or more 3D models; evaluate a second composite distance function using each second feature distance; and re-rank the one or more query 3D models based on results of the evaluated second composite distance function. 17. The system of claim 10 , wherein the composite distance function is computed using a plurality of feature types, wherein a feature type is either shape-based, appearance-based or location-based.