Method and apparatus for encoding geometry patterns, and method and apparatus for decoding geometry patterns
3D models often have a large number of small to medium sized connected components, with small numbers of large triangles, often with arbitrary connectivity. The efficiency of compact representation of large multi-component 3D models can be improved by detecting and representing similarities between components thereof, even if the components are not exactly equal. The invention uses displacement maps for encoding two or more different but similar geometry patterns differentially, based on clustering and a cluster representative surface (CRS). A method for encoding a plurality of geometry patterns comprises detecting and encoding identical copies of geometrical patterns (100), detecting and clustering similar geometry patterns (200), and detecting partial similarity (300). The detecting partial similarity (300) comprises generating a cluster representative surface, generating for at least one clustered geometry pattern a displacement map, and encoding the common surface and the displacement maps.