Vector graphics
From Webcomic Wiki
Vector graphics or geometric modeling is the use of geometrical primitives such as points, lines, curves, and polygons to represent images in computer graphics. It is used by contrast to the term raster graphics, which is the representation of images as a collection of pixels (dots).
The human eye works as a bitmap picture: it catches the image in a mosaic raster of photon recipient nerves, a pixel image. But the brain - according to recent studies - handles it as a vector image. Perhaps because - like in our computers - this is easier to store. It explains why we can recognise simple drawings like cartoons with just outlines because this is so close to what our brain makes of the visual world anyway. It also serves as an explanation for the fact that logos and signs with easy and geometric shapes are easier remembered and recognised.
[edit] Overview
Virtually all modern current computer video displays translate vector representations of an image to a raster format. The raster image, containing a value for every pixel on the screen, is stored in memory and the entire screen is repainted 30 or more times per second.
Starting in the earliest days of computing in the 1950s and into the 1980s, a different type of display, the vector graphics system, was used. In these systems the electron beam of the CRT display monitor was steered directly to trace out the shapes required, line segment by line segment, with the rest of the screen remaining black. This process was repeated many times a second to achieve a flicker-free or near flicker-free picture. These systems allowed very high-resolution line art and moving images to be displayed without the (for that time) unthinkably huge amounts of memory that an equivalent-resolution raster system would have needed.
One of the first uses of vector graphic displays was the US SAGE air defense system. Vector graphics systems were only retired from U.S. en route air traffic control in 1999 and are likely still in use in military and specialized systems. Subsequent vector graphics systems include Digital's GT40 [1]. There was a home gaming system that used vector graphics called Vectrex [2] as well as various arcade games like Asteroids and Space Wars [3] The Tektronix-4014 [4] also deserves a mention even though the display was static.
The term vector graphics is mainly used today in the context of two-dimensional computer graphics. It is one of several modes a programmer can use to create an image on a raster display. Other modes include text, multimedia and 3-d rendering. Virtually all modern 3-d rendering is done using extensions of 2-d vector graphics techniques. Plotters used in technical drawing still draw vectors directly to paper.
