Polygons are used in

computer graphics Computer graphics deals with generating images with the aid of computers. Today, computer graphics is a core technology in digital photography, film, video games, cell phone and computer displays, and many specialized applications. A great de ...

to compose images that are

three-dimensional Three-dimensional space (also: 3D space, 3-space or, rarely, tri-dimensional space) is a geometric setting in which three values (called ''parameters'') are required to determine the position of an element (i.e., point). This is the informa ...

in appearance. Usually (but not always) triangular,

polygon In geometry, a polygon () is a plane figure that is described by a finite number of straight line segments connected to form a closed ''polygonal chain'' (or ''polygonal circuit''). The bounded plane region, the bounding circuit, or the two to ...

s arise when an object's surface is modeled, vertices are selected, and the object is rendered in a

wire frame model A wire-frame model, also wireframe model, is a visual representation of a three-dimensional (3D) physical object used in 3D computer graphics. It is created by specifying each edge of the physical object where two mathematically continuous ...

. This is quicker to display than a shaded model; thus the polygons are a stage in computer animation. The ''polygon count'' refers to the number of polygons being rendered per

frame A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (con ...

. Beginning with the

fifth generation of video game consoles The fifth-generation era (also known as the 32-bit era, the 64-bit era, or the 3D era) refers to computer and video games, video game consoles, and handheld gaming consoles dating from approximately October 4, 1993 to March 23, 2006. For home c ...

, the use of polygons became more common, and with each succeeding generation, polygonal models became increasingly complex.

Competing methods for rendering polygons that avoid seams

* Point **

Floating Point In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can b ...

** Fixed-Point **

Polygon In geometry, a polygon () is a plane figure that is described by a finite number of straight line segments connected to form a closed ''polygonal chain'' (or ''polygonal circuit''). The bounded plane region, the bounding circuit, or the two to ...

**because of

rounding Rounding means replacing a number with an approximate value that has a shorter, simpler, or more explicit representation. For example, replacing $ with $, the fraction 312/937 with 1/3, or the expression with . Rounding is often done to ob ...

, every

scanline A scan line (also scanline) is one line, or row, in a raster scanning pattern, such as a line of video on a cathode ray tube (CRT) display of a television set or computer monitor. On CRT screens the horizontal scan lines are visually discernible, ...

has its own direction in space and may show its front or back side to the viewer. *

Fraction (mathematics) A fraction (from la, fractus, "broken") represents a part of a whole or, more generally, any number of equal parts. When spoken in everyday English, a fraction describes how many parts of a certain size there are, for example, one-half, eight ...

Bresenham's line algorithm Bresenham's line algorithm is a line drawing algorithm that determines the points of an ''n''-dimensional raster that should be selected in order to form a close approximation to a straight line between two points. It is commonly used to draw li ...

**Polygons have to be split into

triangle A triangle is a polygon with three edges and three 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, any three points, when non- colline ...

s **The whole triangle shows the same side to the viewer **The point numbers from the

Transform and lighting Transform, clipping, and lighting (T&L or TCL) is a term used in computer graphics. Overview Transformation is the task of producing a two-dimensional view of a three-dimensional scene. Clipping means only drawing the parts of the scene that w ...

stage have to converted to

Barycentric coordinates (mathematics) In geometry, a barycentric coordinate system is a coordinate system in which the location of a point is specified by reference to a simplex (a triangle for points in a plane, a tetrahedron for points in three-dimensional space, etc.). The bar ...

**Used in raytracing

References

{{DEFAULTSORT:Polygon (Computer Graphics) 3D computer graphics

Competing methods for rendering polygons that avoid seams

See also

References