It is also a good technic to display very coloured layers.
==Raster==
Here I will refer to the traditional raster, where the colour for one pen is changed once each line. The final result is usually a horizontal bar of colour that covers the whole width of the screen.
==Split Rasters==
Split rasters are made by changing the colour for one pen more than once on each line. The final result is usually more than one horizontal bar of colour side by side covering the whole width of the screen.
==Raster scroll==
This is a form of split raster, but where the position of the first raster is offset each frame. The effect is that the entire split raster moves in the horizontal. If you then move the bars accross the screen then you can make the bars scroll. Ultimately, this can be used to form letters and a horizontal scrolling message.
==Diagonal rasters==
This is a form of traditional raster, but instead of timing to ensure that colours are always changed at the same time on each successive line, the timing is altered so that the colours occur at successively earlier positions on succeeding lines. The effect can be done by ensuring each line does not take 64 cycles, but instead 63 or less cycles depending on the effect wanted.
==Exemples of Raster effect in Games==