/We apologize for multiple messages/ This is to invite you to participate in the following track of "SHREC'21 - 3D Shape Retrieval Contest 2021" (https://www.shrec.net/) SHREC'21 track: Fitting simple geometric primitives on point clouds from CAD objects The aim of the track is to evaluate the quality of automatic algorithms for fitting geometric primitives on CAD models represented as point clouds. The goal is to identify the number and the type of simple geometric surface primitives that are present on the surface the CAD model. As simple primitives we mean the classical surface primitives derived from constructive solid geometry, i.e., planes, spheres, ellipsoids, tori, cones and cylinders. The files of a preliminary set of models (approx. 70) will be available on January 15h. The point clouds that will be used for the final evaluation (approx. 30) will be available on January 30th. Results are required by February 14h. For further information see: http://shrec.ge.imati.cnr.it/shrec21_fitting/ Contact: chiara.romanengo(a)ge.imati.cnr.it, andrea.raffo(a)ge.imati.cnr.it Best regards, Chiara Romanengo, Andrea Raffo