frame, Set of connected triangles described by vertices A through F.
A triangle fan is a
primitive in
3D computer graphics
3D computer graphics, or “3D graphics,” sometimes called CGI, 3D-CGI or three-dimensional computer graphics are graphics that use a three-dimensional representation of geometric data (often Cartesian) that is stored in the computer for th ...
that saves on storage and processing time. It describes a set of connected
triangle
A triangle is a polygon with three Edge (geometry), edges and three Vertex (geometry), vertices. It is one of the basic shapes in geometry. A triangle with vertices ''A'', ''B'', and ''C'' is denoted \triangle ABC.
In Euclidean geometry, an ...
s that share one central
vertex
Vertex, vertices or vertexes may refer to:
Science and technology Mathematics and computer science
*Vertex (geometry), a point where two or more curves, lines, or edges meet
*Vertex (computer graphics), a data structure that describes the position ...
(unlike the
triangle strip
In computer graphics, a triangle strip is a subset of triangles in a triangle mesh with shared vertices, and is a more memory-efficient method of storing information about the mesh. They are more efficient than un-indexed lists of triangles, bu ...
that connects the next vertex point to the last two used vertices to form a triangle), possibly within a
triangle mesh
In computer graphics, a triangle mesh is a type of polygon mesh. It comprises a set of triangles (typically in three dimensions) that are connected by their common edges or vertices.
Many graphics software packages and hardware devices can ...
. If is the number of triangles in the fan, the number of vertices describing it is . This is a considerable improvement over the vertices that are necessary to describe the triangles separately. The
graphics pipeline
In computer graphics, a computer graphics pipeline, rendering pipeline or simply graphics pipeline, is a conceptual model that describes what steps a graphics system needs to perform to Rendering (computer graphics), render a ...
can take advantage by only performing the viewing transformations and lighting calculations once per vertex. Triangle fans are deprecated in
Direct3D10 and later.
Any
convex polygon
In geometry, a convex polygon is a polygon that is the boundary of a convex set. This means that the line segment between two points of the polygon is contained in the union of the interior and the boundary of the polygon. In particular, it is a ...
may be triangulated as a single fan, by arbitrarily selecting any point inside it as the center.
See also
*
Triangle strip
In computer graphics, a triangle strip is a subset of triangles in a triangle mesh with shared vertices, and is a more memory-efficient method of storing information about the mesh. They are more efficient than un-indexed lists of triangles, bu ...
*
Fan triangulation
In computational geometry, a fan triangulation is a simple way to triangulate a polygon by choosing a vertex and drawing edges to all of the other vertices of the polygon. Not every polygon can be triangulated this way, so this method is usua ...
References
Computer graphics
{{Compu-graphics-stub
