Hierarchical triangular mesh

Hierarchical Triangular Mesh (HTM) is a kind of quad tree based on subdivision of a distorted octahedron, used for mesh generation in 3-D computer graphics and geometric data structures.^[1]

Diagram of Hierarchical Triangular Mesh (HTM). The spherical polygons are the projection of the edges of the octahedron onto the circumscribing sphere.

Functions

• It provides a systematic indexing method for objects localized on a sphere.^[2]
• It is an efficient method for searching different resolutions like arc seconds or hemispheres.^[1]
• It can be used as a method to subdivide the spherical surface into triangles of nearly equal shape and size.^[2]

See also

• HEALPix
• Quadrilateralized spherical cube
• Geodesic grid