Re:Writing a game from first principles in 65c02 – Part One
by duskwuff on Saturday May 29, 2021 @05:07PM
(#27328226)
The 2600 was a whole wacky world of its own. The system didn't actually have any native support for sprites or bitmapped graphics! The graphics chip was designed to implement games similar to Pong, and only natively supported drawing a few blocks of color; games which wanted to display more complex graphics (which is to say, almost all of them) had to abuse this hardware by modifying its registers on a per-scanline (or even an intra-scanline) basis.
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Re:Writing a game from first principles in 65c02 – Part One
by bitwize on Saturday May 29, 2021 @05:41PM
(#27328449)
The Atari 2600 supported sprites: two "players", two "missiles", and one "ball", that could be moved freely over the low resolution playfield. However, their bitmaps were only one pixel high; you had to change them on each scanline in order to get taller images.
Rectangular bitmap sprites may have debuted in consumer hardware with the TI-99/4 in 1979; the term "sprite" comes from the technical documentation for that computer.
Re:Writing a game from first principles in 65c02 – Part One
by nicetryguy on Saturday May 29, 2021 @05:31PM
(#27328380)
Right, all you could do with the "player" objects was point them at a different byte every scanline, write the X value into the register, and it would paint the "1's" as "pixels" in that byte on that particular scanline with that X value. It was up to the programmer to multiplex them on a per scanline basis. No framebuffer whatsoever. Fun stuff!