Watching Onedimensional (Atari 8-bit)

Running over last weekend was the latest edition of the Atari-centric Silly Venture party which has spent nearly two decades bringing fans of all things Atari together to party, chat and do demo-ish things; there were some great releases over the various Atari platforms as always, but I found myself drawn to one particularly old school demo which took part in the 16K Atari 8-bit competition. It’s called Onedimensional, was coded by Shadow of Noice and is basically a 1980s-style raster intro which features a four colour logo parked at the top of the screen, a double font scrolling message trundling past at the bottom and industrial quantities of raster bars dancing like nobody is watching between them.

This really couldn’t be described as pushing the Atari 8-bit’s boundaries and Shadow himself commented that it’s a “compo filler” in the scroller, but regular readers will know I love me some raster bars so a new production that does lots of variations on that particular theme is always going to catch my eye. The graphics are reasonable and do what they’re there for – Rocky’s logo is well drawn but part of me wants a teensy bit more colour – whilst the music was composed by Tobikomi (who appears to be a newcomer to the POKEY by the look of it) and is quirky but fun, suiting the on-screen action well especially since all of the effect and logo colour changes have been synchronised to it.

To be honest, I resisted the urge to do something along similar lines to this for about a decade – even when I finally gave in there were excuses like using 256 colours in MD201701 to hide behind rather than just going hell for leather with a no-nonsense, WSYNC-powered colour splitter – because the potential backlash from hardened Atarians to something like that is, quite frankly, terrifying! But Shadow made of sterner stuff than me and ran with it, doing every solid job overall especially when considering the small memory footprint he was working within.

Watching Five To Five (Atari 8-bit)

I’m not actually sure when Five To Five was released; there’s a YouTube video which says 1989 in the description and one visitor to Pouet commented about watching it in 1990, but there’s no date on any of the archives I usually grab Atari 8-bit files from. It’s a single-parter produced by Polish game developers Mirage Software – again according to the aforementioned YouTube description, it was put out as a preview for a game that wasn’t actually released – and features solid graphics, a brilliant piece of music by Jakub Husak and some clever use of the Atari 8-bit’s video hardware.

There’s a couple of effects of note, specifically the oscillating snake picture in the middle of the screen and a moving chessboard at the bottom; the latter is simple enough and works in the “traditional” manner which games like Trailblazer employ, having a series of triangles defining the shape and changing two colour registers for each row of squares, making the gaps wider between those colour changes near the bottom of the effect and narrower at the top.

The main effect is also relatively simple in technical terms but the implementation is what sells it; the shape of the Atari 8-bit’s screen is handled by a series of instructions called a display list and these commands can specify which mode is being used for each line of the screen, if horizontal or vertical fine scrolling is enabled and, most importantly in this case, where in memory to start fetching graphics data. There’s one of these memory selection commands for every scanline of the effect and the addresses following them are rewritten based on a sine curve. This technique wasn’t new and had already been used in the past to manipulate the display in programs like Jeff Minter’s Colourspace but the trapezoid frame around the picture adds to the overall effect, making appear to be moving in 3D.

This second screenshot is a glimpse behind the curtain for both effects that appears during the fraction of a second long pause between the display list being enabled and Five To Five‘s main code kicking in. The top of the snake picture is there without any distortion applied – the rest of the image is of course in memory after that part finishes, but the display list doesn’t have instructions to display it – so the shape of the frame more obvious and those triangles I mentioned that are used for the chessboard are visible as well.

Playing Sea Dragon (Atari 8-bit)

A life on the ocean wave… or at least below it with Sea Dragon where the player takes control of the titular submarine. This game started life on the Tandy TRS-80 and was ported fairly far and wide – there are versions for the Apple II, C64 and IBM PC – but we’re looking at the Atari 8-bit version here because that’s the one I’ve enjoyed playing the most personally – although the Spectrum conversion from 2010 gets a close second – and that’s as good a reason as any.

The first and most common enemies are sea mines which lie in wait at the bottom of the ocean, slipping their moorings when the player is in range to drift slowly upwards towards them and not leaving much time to react. These can be torpedoed at any point as long as the submarine has a clear line of sight so the threat they pose is limited, but it doesn’t take long before they’re joined by other hazards including automated gun emplacements in the underwater caverns and ships which sit on the surface and drop depth charges into the water; the charges themselves can at least be shot to give the sub a little more wiggle room, but a close eye on the other enemies has to be kept whilst doing so.

Along with these direct threats to the submarine, there’s also an air gauge to worry about which is constantly dropping whilst submerged. This can be replenished by going up to the surface and waiting for the tanks to refill – one nice little detail is that this process isn’t immediate – although that can’t be done when traversing the underwater caves so spending some time at the surface to stock up before each of these sections is a must. Staying in one place for too long really does put the craft in harm’s way as the game progresses as well, so refuelling will become quite perilous.

Sea Dragon obviously takes a few cues from Scramble – the sea mines work in a very similar way to Konami’s ground-to-air rockets for example – but some thought has gone into reworking that design for the underwater setting and I particularly like how the fuel gauge has been updated. To my mind at least, the Atari 8-bit implementation stands out from the rest for it’s simple, chunky but still effective graphics and having fairly minimal sound effects overlaid onto the constant sonar pings, adding far more to the slower, tense atmosphere Sea Dragon has than in-game music would have done.