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Some platforms (such as the Commodore 64, [[Amiga]], Sega Master System,<ref>{{Cite web |url=https://www.smspower.org/uploads/Development/richard.txt |title=Archived copy |access-date=2018-09-04 |archive-url=https://web.archive.org/web/20171109095042/http://www.smspower.org/uploads/Development/richard.txt |archive-date=2017-11-09 |url-status=live }}</ref> PC Engine/TurboGrafx-16,<ref>{{cite web |url=http://cgfm2.emuviews.com/txt/pcetech.txt |title=Archived copy |access-date=2014-03-18 |url-status=dead |archive-url=https://web.archive.org/web/20140318183739/http://cgfm2.emuviews.com/txt/pcetech.txt |archive-date=2014-03-18 }}</ref> [[Mega Drive|Sega Mega Drive/Genesis]], [[Super Nintendo Entertainment System|Super NES]], [[Game Boy]], [[Game Boy Advance]] and [[Nintendo DS]]) provide a [[horizontal blank interrupt]] for automatically setting the registers independently of the rest of the program. Others, such as the NES, require the use of cycle-timed code, which is specially written to take exactly as long to execute as the video chip takes to draw one scanline, or [[Interrupt request|timers]] [[Memory management controller|inside game cartridges]] that generate [[Raster interrupt|interrupts]] after a given number of scanlines have been drawn. Many NES games use this technique to draw their status bars, and ''[[Teenage Mutant Ninja Turtles (arcade game)#Ports|Teenage Mutant Ninja Turtles II: The Arcade Game]]'' and ''[[Vice: Project Doom]]'' for NES use it to scroll background layers at different rates.
More advanced raster techniques can produce interesting effects. A system can achieve a very effective depth of field if layers with rasters are combined; ''[[Sonic the Hedgehog (1991 video game)|Sonic the Hedgehog]]'', ''[[Sonic the Hedgehog 2 (16-bit)|Sonic The Hedgehog 2]]'', ''[[ActRaiser]]'', ''[[Lionheart (video game)|Lionheart]]'', [[Kid Chaos (video game)|Kid Chaos]] and ''[[Street Fighter II]]'' used this effect well. If each scanline has its own layer, the ''[[Pole Position (video game)|Pole Position]]'' effect is produced, which creates a pseudo-3D road (or a pseudo-3D ball court as in ''[[NBA Jam (1993 video game)|NBA Jam]]'') on a 2D system.
If the display system supports rotation and scaling in addition to scrolling—an effect popularly known as [[Mode 7]]—changing the rotation and scaling factors can draw a projection of a plane (as in ''[[F-Zero (video game)|F-Zero]]'' and ''[[Super Mario Kart]]'') or can warp the playfield to create an extra challenge factor.
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