In a context of full cooperative data exchanges, frequent transfers between specialized software and remote design and manufacturing, fluidity is the key. It is thus important to reduce the size of data encoding files in order to ease their manipulation. In particular, in the case of 3D-geometry-based processes, triangulated meshes are often used. In such files, the 3D points are localized in space thanks to three coordinates. In order to reduce the size of geometry files, this paper investigates the use of an indexing mechanism to encode these floating-point coordinates.