Vertical Raster Bars
A similar effect can be generated vertically, although it often does not extend into the border area. To generate vertical bars, the same line of video memory is repeatedly output every scanline. At the top of the frame, the video memory is typically blank, and every horizontal blanking interval it is updated with a new "bar" in a slightly different position, creating a "stepped" effect.
Vertical raster bars are often called Kefrens bars, after the Amiga demo group that popularized them. However, the effect was implemented earlier by the Alcatraz demo group.
Read more about this topic: Raster Bar
Famous quotes containing the words vertical and/or bars:
“I tell you, hopeless grief is passionless;
That only men incredulous of despair,
Half-taught in anguish, through the midnight air
Beat upward to God’s throne in loud access
Of shrieking and reproach. Full desertness,
In souls as countries, lieth silent-bare
Under the blanching, vertical eye-glare
Of the absolute Heavens.”
—Elizabeth Barrett Browning (1806–1861)
“The last public hanging in the State took place in 1835 on Prince Hill.... On the fatal day, the victim, a man named Watkins, peering through the iron bars of his cell, and seeing the townfolk scurrying to the place of execution, is said to have remarked, ‘Why is everyone running? Nothing can happen until I get there.’”
—Administration for the State of Con, U.S. public relief program (1935-1943)