// 2024-02-08 // by Elder0010
Commodore 64 one file demo by Onslaught
Release date: 28/04/2012
Credits:
This demo marks the start of my collaboration with Psycho8580 and introduced me to some music syncing techniques as well as some raster tricks. It was made for the Gubbdata Party (1st edition) demo competition. It reached position #02. The music by Psycho8580 is one of my favourite C64 tunes and I am still proud of this demo to this day. Freshness coded the checkerboard effect and the lower border scroller.
The chessboard is a fpp sprite routine realised using 7 sprites on standard text mode. Each sprite is up one pixel than the preceeding one. The whole block can be moved vertically by 7 or 14 pixels.
This allows to use all but the last byte of every sprite definition involved.
The tech tech has been done using 10 different charsets. The charsets have been generated with a custom C tool built for the demo. They share the same screen table, but they are shifted 8px each other.
The lower border scroller is based on a $3fff trick and sprites.
The music sync has is done by reading the memory location used by the player routine.
Also, check out the tune used in the note. It’s very atmospheric and a personal favourite of mine.