Release notes – Clone Stars

It’s time for another release dear reader, and after we looked at the Atari Stars Demo by the GPS a few weeks ago, it probably won’t come as much of a surprise that this latest emission is for the Atari 8-bit and called Clone Stars – because we’re nothing if not consistent with our naming policy here at C64CD!

Clone Stars (Atari 8-bit)The overall shape of the original demo has been retained with the bitmapped picture and hardware sprite generated parallax starfield bookended between a line of static text and a scrolling message, but the starfield has been “beefed up” a little with some colour splits and the playfield graphics – which were originally convereted from the Amiga, although your correspondent’s memory refuses to recall any detail on the matter[1] – have been widened to tidy the layout up a little. The scrolling message has been handled in the “traditional” manner in keeping with the original so nothing is actually moving through the Atari’s memory and, since the original relied on a ripped Rob Hubbard tune from Jet Set Willy, Clone Stars uses a cover version of his main theme from the game Commando on the C64 which was arranged by a friend of your correspondent.

Updating of the starfield has been split into two chunks; the faster moving coloured stars are actually refreshed during the loop which displays them – their current position is loaded into the accumulator anyway so the overhead within that loop to add a speed value and write it back to memory isn’t too prohibitive – whilst the slower moving grey stars have a fixed speed of one pixel every second frame and are the last thing processed before the end of the display list interrupt.

The author will no doubt whine inanely as he did previously about relevance to his topic, but the author regularly strays from his own topic in a most hypocritical manner and, as noted on several occasions now, your correspondent can do whatever he pleases and isn’t bound by the author’s topic anyway. As always your correspondent will end on a small disclaimer to point out that, whilst the source code is available from Github as is always the case for C64CD releases, it’s very sensible indeed to keep a decent reference guide handy for the various Atari 8-bit video registers such as either De Re Atari or Atari Roots.

[1] An update as of the 16th of February, your correspondent stumbled across the original picture in 3D Demo II by Anarchy.

 

 

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One Response to Release notes – Clone Stars

  1. Pingback: DRAWING THE LINE – PART 4 | commodore64crap

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