Surfel is an abbreviation of "surface element". In 3D computer graphics

3D computer graphics

3D computer graphics are graphics that use a three-dimensional representation of geometric data that is stored in the computer for the purposes of performing calculations and rendering 2D images...

, the use of surfels is an alternative to polygonal modeling

Polygonal modeling

In 3D computer graphics, polygonal modeling is an approach for modeling objects by representing or approximating their surfaces using polygons. Polygonal modeling is well suited to scanline rendering and is therefore the method of choice for real-time computer graphics...

. An object is represented by a dense set of points or viewer-facing discs holding lighting information. Surfels are well suited to modeling dynamic geometry, because there is no need to compute topology information such as adjacency lists. Common applications are medical scanner data representation, real time rendering of particle systems, and more generally, rendering surfaces of volumetric data by first extracting the isosurface.