Projective geometry
In mathematics, projective geometry is the study of geometric properties that are invariant under projective transformations. This means that, compared to elementary geometry, projective geometry has ...
Projective geometry - Wikipedia
Projective polyhedron
In geometry, a (globally) projective polyhedron is a tessellation of the real projective plane. These are projective analogs of spherical polyhedra – tessellations of the sphere – and toroidal polyhed...
Projective polyhedron - Wikipedia
Imaginary point
In geometry, in the context of a real geometric space extended to (or embedded in) a complex projective space, an imaginary point is a point not contained in the embedded space.
In terms of homoge...
Direct linear transformation
Direct linear transformation (DLT) is an algorithm which solves a set of variables from a set of similarity relations:where and are known vectors, denotes equality up to an unknown scalar multiplic...
Möbius transformation
In geometry and complex analysis, a Möbius transformation of the plane is a rational function of the formof one complex variable z; here the coefficients a, b, c, d are complex numbers satisfying ad −...
Möbius transformation - Wikipedia
Visual hull
A visual hull is a geometric entity created by shape-from-silhouette 3D reconstruction technique introduced by A. Laurentini. This technique assumes the foreground object in an image can be separated ...
Visual hull - Wikipedia
Projective line
In mathematics, a projective line is, roughly speaking, the extension of a usual line by a point called a point at infinity. The statement and the proof of many theorems of geometry are simplified by ...
Projective line - Wikipedia
Configuration (geometry)
In mathematics, specifically projective geometry, a configuration in the plane consists of a finite set of points, and a finite arrangement of lines, such that each point is incident to the same numbe...
Configuration (geometry) - Wikipedia
3D projection
3D projection is any method of mapping three-dimensional points to a two-dimensional plane. As most current methods for displaying graphical data are based on planar two-dimensional media, the use of ...
Complex projective space
In mathematics, complex projective space is the projective space with respect to the field of complex numbers. By analogy, whereas the points of a real projective space label the lines through the or...
Complex projective space - Wikipedia
Branched covering
In mathematics, branched covering is a term used to describe a map that is almost a covering map, except on a small set.
In topology, a map is a branched covering if it is a covering map everywher...
Projective harmonic conjugate
In projective geometry, the harmonic conjugate point of an ordered triple of points on the real projective line is defined by the following construction:What is remarkable is that the point D does not...
Projective harmonic conjugate - Wikipedia
Lénárt sphere
A Lénárt sphere is a teaching and educational research model for non-Euclidean geometry, especially spherical geometry, spherical trigonometry, and projective geometry. The Lénárt sphere has been call...
Lénárt sphere - Wikipedia
Projective line over a ring
In mathematics, the projective line over a ring is an extension of the concept of projective line over a field. Given a ring A with 1, the projective line P(A) over A consists of points identified by ...
Planar ternary ring
In mathematics, an algebraic structure consisting of a non-empty set and a ternary mapping may be called a ternary system. A planar ternary ring (PTR) or ternary field is special type of ternary...
Translation plane
In mathematics, a translation plane is a particular kind of projective plane, as considered as a combinatorial object. In a projective plane, represents a point, and represents a line. A central col...
Blocking set
In geometry, specifically projective geometry, a blocking set is a set of points in a projective plane which every line intersects and which does not contain an entire line. The concept can be general...
Hessian pair
In mathematics, a Hessian pair or Hessian duad, named for Otto Hesse, is a pair of points of the projective line canonically associated with a set of 3 points of the projective line. More generally, ...
Imaginary curve
In algebraic geometry an imaginary curve is an algebraic curve which does not contain any real points.For example, the set of pairs of complex numbers satisfying the equation forms an imaginary circ...
Real projective line
In projective geometry and real analysis, the real projective line (also called the one-point compactification of the real line, or the projectively extended real numbers), is the set , also denoted b...
Real projective line - Wikipedia
Five points determine a conic
In Euclidean, non-projective geometry, just as two (distinct) points determine a line (a degree-1 plane curve), five points determine a conic (a degree-2 plane curve). There are additional subtleties ...
Five points determine a conic - Wikipedia
Quasifield
In mathematics, a quasifield is an algebraic structure where + and are binary operations on Q, much like a division ring, but with some weaker conditions.
A quasifield is a structure, where + a...
Projectivization
In mathematics, projectivization is a procedure which associates with a non-zero vector space V a projective space , whose elements are one-dimensional subspaces of V. More generally, any subset S of ...
Hall plane
In mathematics, a Hall plane is a non-Desarguesian projective plane constructed by Marshall Hall Jr. (1943). There are examples of order p for every prime p and every positive integer n provided p...
Veblen–Young theorem
In mathematics, the Veblen–Young theorem, proved by Oswald Veblen and John Wesley Young (1908, 1910, 1917), states that a projective space of dimension at least 3 can be constructed a...
Riemann sphere
In mathematics, the Riemann sphere, named after the 19th century mathematician Bernhard Riemann, is a model of the extended complex plane, the complex plane plus a point at infinity. This extended pla...
Riemann sphere - Wikipedia
Hurwitz surface
In Riemann surface theory and hyperbolic geometry, a Hurwitz surface, named after Adolf Hurwitz, is a compact Riemann surface with precisely automorphisms, where g is the genus of the surface. This nu...
Hurwitz surface - Wikipedia
Incidence (geometry)
In geometry, the relations of incidence are those such as "lies on" between points and lines (as in "point P lies on line l"), and "intersects" (as in "line l1 intersects line l2"). That is, they are...
Incidence (geometry) - Wikipedia