Computer graphics.

Computer graphics (also computer graphics) — an area of activity in which computers are used for image synthesis and processing of visual information obtained from the real world. Also computer graphics is called and the result of this activity.
The first computers did not have separate tools for working with graphics, however, already been used to obtain and image processing. Programming the memory of the first electronic machines built on the basis of a matrix of lamps, it was possible to obtain patterns.
In 1961, programmer S. Russell headed the project to create the first computer game with graphics. The creation of the game "Spacewar" ("Space war") took about 200 man-hours. The game was created on the machine PDP-1.
In 1963, American scientist Ivan Sutherland has created a software-hardware complex of Sketchpad, which allows you to draw points, lines, and circles on the handset digital pen. Supported basic operations with primitives: move, copy, etc. In fact, it was the first vector editor, implemented on the computer. Also the program can be called the first graphic interface, and it was such even before the emergence of the term.
In the mid-1960s, were the development in industrial applications of computer graphics. So, under the leadership of T. Mofetta and N. Taylor's firm Itek has developed a digital electronic drafting machine. In 1964, General Motors introduced the computer-aided design DAC-1, developed jointly with IBM.
In 1968 a group led by N. N. Konstantinov was created by computer mathematical model of the motion of the cat. BESM-4, performing a program written for solving differential equations, sketch cartoon "Kitty", which for its time was a breakthrough. For visualization was used alphanumeric printer.
Substantial progress computer graphics have experienced with the ability to memorize images and display them on a computer display, cathode-ray tube.


Frame cartoon "Kitty"

On how to specify images graphics can be divided into three categories:

Two-dimensional graphics
Two-dimensional computer graphics categorized according to the type of representation of the graphic information and the image processing algorithms. Typically, computer graphics are divided into vector and raster, although segregated into even and fractal type image representation.

Vector graphics
Acterna graphics represents an image as a set of geometric primitives. Usually, as they are usually points, lines, circles, rectangles, as well as the General case, splines of some order. Objects are assigned to some attributes, e.g. line thickness, fill color. The picture is stored as a set of coordinates, vectors and other numbers characterizing the set of primitives. When playing overlapping objects has the value of their order.

The image in vector format gives scope for editing. The image can be losslessly scaled, rotated, deformed, and as an imitation of three-dimensionality in vector graphics easier than in a raster. The fact that each such conversion actually is: the old image (or fragment) is erased, and instead build a new. The mathematical description of a vector figure remains the same, only change the values of some variables, for example ratios. When you convert bitmap source data is only a description of the set of pixels, therefore there is the problem of replacement of a smaller number of pixels on a larger (zoomed in) or larger to smaller (decreasing). The easiest way is to replace single pixel by multiple of the same color (the copy method of the nearest pixel: Nearest Neighbour). More sophisticated methods use interpolation algorithms in which the new pixels receive some color code which is calculated on the basis of codes of the colors of neighboring pixels. In this way you zoom in Adobe Photoshop (bilinear and bicubic interpolation).
However, not every image can be represented as a set of primitives. This way of representation is good for diagrams used for scalable fonts, business graphics, is widely used for creating cartoons and commercials just different content.

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Vector-based drawing sample

Raster graphics
Raster graphics always operates on a two-dimensional array (matrix) of pixels. Each pixel is mapped to a value — brightness of color, transparency or a combination of these values. The raster image has some number of rows and columns.
Without loss of raster images can only be reduced, although some details of the image then disappears forever, or in vector representation. The increase of the raster image turns into a beautiful view of the enlarged squares of a particular color, which used to be pixels.
In raster form representable by any image, however, this storage method has its drawbacks: more memory needed to work with images, loss when editing.


Example bitmap

Fractal graphics
A fractal object, the individual elements of which inherit properties of the parent structures. Since a more detailed description of the elements on a smaller scale happens on a simple algorithm to describe such an object only by several mathematical equations.
Fractals allow us to describe whole classes of images, for a detailed description of which requires relatively little memory. On the other hand, to images outside of these classes, fractals applicable weak.


Fractal tree

Three-dimensional graphics (3D)
Operates with three-dimensional graphics objects in three-dimensional space. Usually results represent a flat picture projection. Three-dimensional computer graphics are widely used in film, computer games.
In computer graphics, all objects are usually represented as a set of surfaces or particles. Minimal surface is called a polygon. As the ground is usually chosen triangles.

All the visual transformations in 3D control matrix (see also: affine transformation in linear algebra). In computer graphics, used three kinds of matrices:
the rotation matrix
the translation matrix
matrix scaling

Any polygon can be represented as a set of coordinates of its vertices. So, the triangle is 3 vertices. The coordinates of each vertex represent the vector (x, y, z). Multiplying the vector by a corresponding matrix, we obtain a new vector. Making this transformation to all the vertices of the polygon, we get a new ground and transforming all polygons, get the new object is rotated/shifted/scaled relative to the source.
Held annually, the contests of three-dimensional graphics, such as Magick next-gen or the Dominance War.

CGI graphics
CGI — Computer Generated Images (Computer Generated Objects)

A representation of the colors in the computer
For the transmission and storage of colors in computer graphics are different forms of submission. In the General case, color is a set of numbers, coordinates in some color system.
Standard methods of storing and processing the colors in the computer due to the properties of human vision. The most common system for RGB displays and CMYK for work in typography.
Sometimes system is used with more than three, the number of components. Coded reflection spectrum or emission source that allows you to more accurately describe the physical properties of color. Such schemes are used in photorealistic three-dimensional rendering.


System color of RGB

The real side graphics
Any image on the monitor, because of its plane, it becomes a raster, as the monitor is a matrix, it consists of columns and rows of three-Dimensional graphics exists only in our imagination, since what we see on the monitor is the projection of the three-dimensional shape, and create the space ourselves. Thus, the rendering of graphics is only raster and vector, and the visualization is only raster (pixels) and the number of these pixels depends on the method of setting an image.