BoulderDash for BBC Electron

by Andrew Bennett

I first came across BoulderDash on the ZX-Spectrum and was totally awestruck by the game. A year or two later, I owned a computer called an "Acorn Electron" (a poor man's BBC); it was a 32K 6502 machine.

Once I decided that I wanted to start writing in assembler, (took about a week to learn) I decided to start work on writing an "improved" version of the game. I already had hundreds of new ideas for additional features, and after about 3 months I had a pretty fast smooth version to play around with. Some of my new features were:

There were a few more things I tried but, I've forgotten half of them.

Anyway, at the time when I had a perfectly good game engine,I heard that a software company called TyneSoft were in the process of doing conversions of First Star games for the BBC/Electron. So I headed down to the Olympia Computer Show and showed them a videotape of my game.

They seemed quite impressed, and said they would be in touch....

After a few days, I got a phone call saying that they wanted to publish a version of the original BoulderDash (I hadn't bothered showing off my own ideas). The process of actually turning my game into a simple copy of the original should have been fairly straight-forward.

In fact it took over 3 months, meaning that I missed a Christmas release date. The reason was simple: I simply couldn't figure out what pseudo-random method Peter Liepa had used to generate much of the background patterns in each cave (ie random sprinklings of boulders/spaces etc.) TyneSoft said they would try to get the information for me but never did. Eventually I had to painstakingly go through every cave on the game (using a copy of the original game on the MSX), copy down the map for each level, then find some way of squeezing the 100+ levels into the memory available. On a BBC there was only 32K total memory, 10K of which was needed for the screen.

Anyway, eventually I finished this exhausting task (January 87) and took the disk up to Newcastle. We signed a contract which gave me an advance of £400 and a royalty of 65p per game sold (at £10.00 a copy!) The game got pretty good reviews in the mags and It was a nice feeling walking into a WHSmiths newsagent and seeing copies of my game on the shelves. :)

Despite this, I don't believe it sold that well. The old 8 bit computers were going out of fashion with the arrival of the ST and Amiga. Plus the BBC/Electron share of the market was pretty tiny in the first place. I don't have any real idea of how many copies sold though, the software company never bothered sending any royalties or even information, and after a few phone-calls I gave up trying to get them to pay up.

This experience put me off the idea of writing games for a long time; I had hoped that the royalties would help me with the costs of going back to university to study physics.

I kept my Electron up until the time I could afford an Amiga (A600), after graduating. And finally, I'm starting to get back into coding again. Probably too late, mind. :-/ I just hope the Amiga doesn't fade away just as I'm ready for my second shot at fame. ;-)

A few more thoughts

I believe that the appeal of Boulderdash lies in it's "physics". It's fascinating to see how fairly simple local rules can give rise to surprisingly complex global behavior; essentially it's a universe of fairly simple cellular automata, albeit that one of the objects takes it's actions from the player.

This is what I believe is crucial to a good game, the so called "playability" of a game is related to the simplicity of it's rules, and the complexity of the consequences of those rules.

Even after I'd been writing and testing the game for 6 months, I still found that I could waste hours at a time just setting up weird scenarios and seeing what happened. I only got tired of the game during the tedious business of entering/compressing/testing every cave.

Some more facts

My version ran on the Acorn Electron, BBC model B, BBC master series. It was sold on cassette and also on floppy disk.

The main code took up about 6K! (incredibly optimised; I'm a bit of a perfectionist, hehe), and the data (caves etc) took up about 13K.

Oh, if anyone still has a copy, try pressing "B" on the title screen for a secret credits list!

P.S. To anyone who pirated my game, no sweat. it's not as If I got any royalties anyway. :)

Closing remark

Peter Liepa is an utter genius; I hope he made a fortune!

I just wish I'd had the chance to chat with him.


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