meta: id: stl endian: le application: 3D Systems Stereolithography file-extension: stl xref: wikidata: Q1238229 license: CC0-1.0 doc: | STL files are used to represent simple 3D models, defined using triangular 3D faces. Initially it was introduced as native format for 3D Systems Stereolithography CAD system, but due to its extreme simplicity, it was adopted by a wide range of 3D modelling, CAD, rapid prototyping and 3D printing applications as the simplest 3D model exchange format. STL is extremely bare-bones format: there are no complex headers, no texture / color support, no units specifications, no distinct vertex arrays. Whole model is specified as a collection of triangular faces. There are two versions of the format (text and binary), this spec describes binary version. seq: - id: header size: 80 - id: num_triangles type: u4 - id: triangles type: triangle repeat: expr repeat-expr: num_triangles types: triangle: doc: | Each STL triangle is defined by its 3 points in 3D space and a normal vector, which is generally used to determine where is "inside" and "outside" of the model. seq: - id: normal type: vec3d - id: vertices type: vec3d repeat: expr repeat-expr: 3 vec3d: seq: - id: x type: f4 - id: y type: f4 - id: z type: f4