DYCP
DYCP (Different Y character position) is a term for a programming technique in the demo scene , mainly for 8-bit and 16-bit - home computer .
DYCP refers to a horizontal scroller (ticker) in which the individual letters also move up and down, usually in the form of a sine curve . Both movements (in the X and Y directions) take place as "soft scrolling", ie pixel by pixel , not character by character.
On the C64 , this effect was seen as a spectacular innovation, as the VIC II graphics chip actually provides a fixed 8x8 pixel field for each letter in text mode . A “normal” scroller is mostly purely horizontal; possibly the entire character string moves up and down at the same time in a sine wave. Alternatively, a purely vertical scroller is also possible, in which all characters swing horizontally at the same time.
Until the early 1990s it seemed impossible to move the individual characters vertically against each other with a horizontal scroller. The realization of this effect called "DYCP" is based on the fact that in reality each optically visible character (about 5 pixels high) is composed of two hardware characters (16 pixels high). With multiple offshoots of the same 5-pixel character in the 16-pixel high "double character", flexible shifting of individual characters in the Y direction can be simulated.