Commodore 64 demos
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The Commodore 64 demos for the Commodore 64 (C64) were the first products of the demoscene produced on any home computer, which lead to a similar culture on other platforms.[citation needed]
Simple demo-like music collections were put together on the C64 in 1985 by Charles Deenen, inspired by crack intros, using music taken from games and adding some homemade color graphics. In the following year the movement we now know as the demoscene was born. The Dutch groups 1001 Crew and The Judges, both Commodore 64-based, are often mentioned as the earliest demo groups, both producing pure demos with original graphics and music involving more than just casual work and extensive hardware trickery whilst competing with each other in 1986. At the same time demos from different individuals such as Antony Crowther ("Ratt") had started circulating on Compunet in the United Kingdom.
The first demos on the C64 were not called demos but rather letter, message, supermessage, et cetera. They were initially produced by the same people who cracked software protection, e.g. The 1001 Crew. The label "demo" appeared later.
Among the earliest demos are:
- Game Music 1-9 by The Mercenary Cracker (Charles Deenen, 1985)
- Borderletter from The 1001 Crew (1986)
- Think Twice I-V by The Judges
- Rock This by C64CG (1987)
- Hardcore by The Changeling (1988)
These demos would later evolve into a subculture of their own, resulting in massive parties where demo coders would compete. For the C64, the peak point in time for this culture was the year 1989 in northern Europe. Here, hundreds of Dutch, French, Belgian, German, Danish, Swedish, Finnish and Norwegian groups would meet, for example at Venlo in The Netherlands.
Perhaps the best way of defining what a C64 demo is, would be to say that it exploited a talent. Demos sought to show off the talents of their authors. These talents may have been audio, visual or through programming. It was not unusual to find demos that displayed a single picture, only music tracks or a programming skill.
As the demo scene evolved, programmers would seek to push the limit of the C64. Groups were formed that consisted of members who were skilled in composing music, drawing graphics and programming. Together these members would produce demos that pushed the limits.
Effects thought impossible were achieved in demos, mostly due to undocumented side-effects pertaining to the MOS Technology VIC-II chip. Some examples for VIC-trickery:
- Sprite scrollers were placed in the border. This was probably due to an undocumented leftover from the MOS Technology VIC. By tricking the hardware not to draw the border around the screen, sprites could be moved into this area and displayed.
- Sprites were multiplexed across vertical raster lines (over 8 sprites, sometimes up to 120 sprites). Until the Group Crest released Krestage 3 in May 2007 there was the common perception that no more than 8 sprites could appear at one raster line, but assigning new Y coordinates made it reappear further down the screen.
- FLD (flexible line distance) moved bitmap or character rows an arbitrary number of vertical raster lines apart, making it possible to arbitrarily move any 8 pixel high graphic block smoothly up and down across the screen. Adding sine curves to this positioning gave it nice wavy looks.
- The number of colours displayable in a single 8x8 pixel block in a bitmap were expanded beyond the advertised 4 to all 16 through use of the Flexible Line Interpreter (FLI) mode. As always on c64, FLI works in Hires and Multicolor, with the former allowing twice the x-resolution, but less colors than the latter. FLI causes a 24-pixel wide gray area on the left side of the screen, which is usually hidden
- FPP (Flexible Pixel Positioning), basically a variation of the FLI mode, allows the placement of any line of a character-based graphic at any one y-position, allowing for effects like x-rotating logos, barrel-like effects or smooth stretching and waving over the whole screen.
- Tec-Tec (also Tech-Tech or Tic Tac) assigns a new x-position to any line of a graphic. By using animated sine waves you could for example wave a logo horizontally over the screen, with coders outdoing each other in what kind of graphicmode they did a Tec-Tec on or how big their sinus amplitude was.
- A "Wanker" allows arbitrary x-placement of a bitmap, with the bitmap wrapping around at the border. The unfortunate name was probably mis-translated from the German word "wanken", meaning "to waver", which is what the graphic usually did.
- a Linecruncher allows to scroll a bitmap larger than one screen vertically without having to move all the bitmap data manually.
- AGSP (Any Given Screen Position) is the combination of Wanker and Linecruncher, f.ex. making possible games with colorful bitmap graphics that were scrolling, such as Hannes Sommer's "Fred's Back" series. It is a prime example of how demo effects can influence and advance game development.
Followers of the C64 would see the growth of the demo scene. Gone were the single file demos with one scrolling text and no music. Full disk demos were produced, some of which would play music as the next file loaded, without any delay in the sound.
Hidden parts were included as was the occasional game implemented into a demo.
When the Commodore Amiga appeared, many former C64 demo programmers switched platforms and continued to make demos, but for the Amiga (see Amiga demos). The Atari demos were also heavily influenced by C64 demos. In the United Kingdom, the main alternative demo scene was the one of ZX Spectrum demos.
The C64 was in a time when local BBSes were popular and used to communicate with other people. Software trading via mail was also common. Some C64 enthusiasts lament the loss of the social interaction that locally centered computer activities provided.
[edit] External links
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- C64.CH - The C64 Demo Portal, A site for C64 demos with screenshots
- The Digital Dungeon (TDD), FTP site for C64 demos
- Commodore Scene Database, A scene database where you can get in touch with the sceners themselves or get info about one scener or release or event. Structured, including information (hidden parts), downloads, screenshots, forum.
- C64 Portal C64 demo scene related news, about new releases, parties and other scene related news
- Intros.C64.Org Large online archive of crack intros, the first demoscene productions.
- Driven Online Driven Online - Covering the North American demo scene
- digitalmemoriesdvd.de, Digital Memories: C64 Demos - showcases C64 demos on DVD
- 8Bit Mayhem C64 Scene Music Podcast, Obvious, not so obvious, forgotten and classic Commodore 64 scene music.
- Commodore 64 and PET Demos, Early demos, most written before the demoscene
- Colourful raster bars code
