Saturday 17 November 2012

Favourite Simple Game

Back in the days when a chap ('Bill R') and I ran the DTI Computer Club, Bill brought in a game that was simply a signalling exercise based on a seven-hour shift at Kings Cross railway station in London.

On the BBC Micro this involved a track display screen, switchable to/from a loco yard screen, and operated in four basic colours (Mode 1 on the Beeb) of black, white, yellow and red.

It was very effective, and not all that frenetic – though it does have its moments at certain times during the shift. Being judged Excellent, let alone Outstanding, wasn't exactly easy to achieve, despite the deceptively straightforward nature of the game and its sometimes seemingly leisurely pace.

It was really all about locomotives: getting the right type attached to outgoing trains, getting the locos that brought the trains in subsequently out of the platforms and (in most instances) to the station's loco yard for refuelling. The judgment on one's performance was based around timekeeping – essentially, getting trains out on time, and not keeping them waiting to come in from elsewhere on either of the 'up' lines (Up Fast and Up Slow). Although the slow line arrivals always keep to time, there are random early and late arrivals of various time-shifts on the Up Fast (UF) track.

Come forward several years and Acorn's Archimedes computer and its successors supplanted the old BBC Micros for most purposes (there are still some Beebs running factory machinery and doing other jobs even today). I was delighted when The Data Store in Bromley released an updated version of the KingsX game to run in the newer computers' desktop, fully multi-tasking, and all in one display...


The loco yard now appears at the bottom-right of the display area, rather than in a separate screen as it had to in the old Beeb version. From this we can see a few of the complications.

For example, the West Bay (WB) where the Motorail from time to time asks for a shunting locomotive (Class 31) to take some coaches to the Ferme Park depot near Finsbury Park. The loco Hold point (H) causes a blockage of the Up Slow (US) line every single time a loco moves to or from that point. It takes three minutes (the game advances in half-minute 'jumps' at ten times real life speed, i.e. every three seconds) for a loco to get to the Hold point from a platform or the yard, so it's quite an impediment.

On top of this, the occasional parcels train needs to go into platform 1, so that has to be clear of stock and locos in time for their arrivals – and those trains can (and often do) run early or late, sometimes by quite a few minutes.

The two suburban services – half-hourly to Royston and the hourly semi-fast – have to go on platforms 9 and 10 (and nothing else can go on either of those platforms). Sometimes an incoming train doesn't form an outgoing service, but after a while asks for a (shunting) loco to take it to the depot.

Thus we end up with a surprisingly complex scenario; and at certain times during the simulated work-shift it becomes just about impossible to keep to timetable, even when everything arrives on time thus creating no deviations from a nominal pattern. For example, at just after 9 am, a situation arises whereby there just isn't any platform available for an incoming train until after it has been held up at a red signal outside the station.

There is no way around this; and even solving that with a minimal delay then, of necessity, holds up the outgoing semi-fast suburban service at 0908 hrs, which ends up departing a minute late. There are a couple of other sticky moments in a similar vein; and several periods when, because of other movements, it is very difficult to get all the needed locomotives out of the yard and attached to trains in time for their scheduled departures.

Overall, this relatively simple simulation is actually quite a challenge. A hugely bigger such game, called simply Signal Box, is vast by comparison, and unless one has a display some 4,000 pixels wide will always involve sideways scrolling so one never gets an all-at-once view of what is going on. I can't really do that one, I have found.

Perhaps if someone were to produce something in between that will fit on a modern HD (1,920 pixels wide) display, that might be manageable. In the meantime, I still have an occasional go at KingsX, at which I am now usually rated as Outstanding!

No comments:

Post a Comment

Comments welcome, with 'clean' language, though not anonymous attacks. Note that comment moderation is enabled, and anonymous comments have again been disallowed as the facility has been abused.