Character scrolling method and apparatus

摘要

A method for scrolling, at a desired rate and in a given direction, a graphic character on a display having a predetermined number of actual scan lines and a vertical blanking interval occurring between successive display of all the actual horizontal scan lines of the display, involves the creation of fractional scan lines between successive vertical blanking intervals, the identification of leading and trailing edges of the character and the selective changing of the color or shading of pixels of the leading and trailing edges to effect scolling of the character.