ANTHONY BALL

We quiz the Atari ST and Amiga coder about converting Mercs to the 16-bit home computers

Had you converted any other arcade games prior to Mercs, and were you familiar it?

Yes, Cabal for the NES, at Zippo Games. I then moved across to Tiertex as they wanted me to work on new protection and mastering schemes, and said I could also take my pick of arcade conversions. I really liked Mercs. It was set up for three players and a really fun multiplayer game.

which version came first and did you work from an arcade machine?

The Amiga was first, but while programming that, I knew I had to also make the ST version, so we used the same graphics. We had the arcade machine and it was kept near the artists so they could make sure it looked as close as possible. We didn’t have source code or original artwork, so the whole thing had to be coded and drawn from fresh. I videotaped myself playing the game so I could play it back on my desk over and over. I also made a map editor specifically for the game that would attach to a digitiser – we grabbed the screens from the game in RGB format and converted them to a much smaller colour palette for use on the Amiga and ST.

what sacrifices or changes did you have to make, if any?

We split one of the later levels into two huge levels, because the graphic style changed too much in the arcade game within one level, and the graphics would not have fit into the ST’S memory if I was to make the ST scroll fairly smoothly like the Amiga. On the ST, scores were on a side panel and on the Amiga I tried to reproduce the tall narrow screen layout with the scores overlaid on the screen.

How well do you think you did?

I think it was fairly close, considering the time constraints we had. The Amiga version was better than the ST version, as that was coded in just a couple of weeks at the end of the project. If I’d had more time I could have done things slightly differently, such as using a barrel scroll and introducing more colours. Funnily enough, we weren’t allowed to put our names in the game, but if you press the * key on the keypad then you should see ‘Code:anthony Ball Gfx:david Bland’ on the title screen. We also had a secret ‘clown’s nose’ mega weapon hidden at the very bottom right of the first level, in the sea. When US Gold spotted it we added a ‘secret garden’ full of power-ups and every weapon in the game – including the clown’s nose. It was on level five, I think, and once you have that nose you could kill anything instantly!