The 3D ACIS Modeler (ACIS) is a geometric modeling kernel developed by Spatial Corporation (formerly Spatial Technology), part of Dassault Systèmes. ACIS is used by software developers in industries such as computer-aided design, computer-aided manufacturing, computer-aided engineering, architecture, engineering and construction, coordinate-measuring machine, 3D animation, and shipbuilding. ACIS provides software developers and manufacturers the underlying 3D modeling functionality.
ACIS features an object-oriented C++ architecture with 3D modelling capabilities. ACIS is used to construct applications with hybrid modeling features, since it integrates wireframe model, surface, and solid modeling functionality with both manifold and non-manifold topology, and a set of geometric operations.