The Speed of Mathematics
Javier Barrallo · 2008
Demos are real time computer presentations made within a computer subculture known as Demoscene. Demos shows off the programmer’s ability to squeeze visual effects, graphics and music into very little space, often by generating images and sound data by means of optimized mathematical formulae and algorithms rather than just reading it from a data file. What is Demoscene? Demos are computer animated multimedia presentations made within a computer subculture known as Demoscene. The difference between ordinary animation movies and the demos is that the display of a demo is calculated live at the time it runs on a computer instead of being a playback of previously rendered scenes. The ability of the programmer to create stunning visual effects in real time with the highest possible speed in its rendition is the biggest challenge of Demoscene. Demogroups create demos to demonstrate their abilities in programming, music, drawing, and 3D modeling. Demos are mostly composed of 3D animations mixed with 2D effects and full screen effects with a background of music and sound effects. To push to demo to its limit it is necessary to have a very deep knowledge of Calculus, Algebra and Geometry. Procedural Generation is used for squeezing a lot of impressive audiovisual content like textures, landscapes or lights into very small executable programs. This is simply because a demo has not enough space to store a large amount of pre-made effects, textures, 3D objects, music and artwork. From the first Demos to present day The first demos were created around 1980 to fit in the first block of the floppy disk that was to be loaded into RAM (generally 512 to 4096 bytes). Those demos were a type of electronic graffiti introduced by software crackers prior to the loading of the cracked program. In 1987 IBM introduced the VGA card using an 8-bit depth (256 colors) and a resolution of 640x480 video array. The maximum size of an MS-DOS-based COM executable program was 64 Kilobyte (65536 Bytes). These numbers soon became standards in the Demoscene. Small file sizes have been an integral feature of demos from the very beginning. Nowadays, the practical need for very small demos had diminished, but the willingness to compete in squeezing much into little space had not disappeared.