We chat to one of the team at Emerald Software, responsible for the US Gold conversions of Vigilante

Had you heard of Vigilante?

Only when we started to look at it. We spent a lot of time in the arcades playing games to see what was coming out. It is actually a great arcade game, although the story is funny. It is quick, has multiple levels and impressive graphics – large sprites too, so it looks great.

How did Emerald come to work on Vigilante and which versions did you work on?

We worked for US Gold at the time, so they licensed the development to us. We did other games such as Moonwalker and The Running Man, so we did a few movie licences, too. I was Mr Z80, so any machine that had that chip I worked on. I had a development environment that enabled me to work on the Spectrum and Amstrad at the same time. Mark Cushen was the graphic artist that worked with me on nearly all my Z80 games.

How challenging was the Spectrum port in particular? Really tough. Vigilante has huge graphics so we had to come up with some pretty smart ways of compressing the graphics. So, for example, if you look at the bad guys, they all share the same trousers, whereas in the arcade version they had different trousers. Doing this we save the top and bottom halves of each character separately which saves 50 per cent of graphic space. I also rewrote my sprite engine for Vigilante as it had a lot of moving characters. It could handle up to 48 moving objects on the screen at any one time without slowing down and was pretty impressive at the time. Did you need to make any level sacrifices?

We actually managed to get all the levels in by reducing some of the backgrounds and animations so it wasn’t as complex, but kept the general gameplay the same. It wasn’t as smooth as I would have liked, but it was fast – I was always a believer that if a game played quickly then you had the playability.

The colour/black-and-white option was a neat addition Getting colour in wasn’t easy, so we offered both. This worked well and you could even turn it on or off ingame. On some machines it looked really great and I kept it for future games as it was a great idea to add for players.

How do you think you did in retrospect?

I think it was one of my better games. It’s fast and playable and went down well. It wasn’t perfect – I would have liked the animation to have been smoother – but it was quick. It reached the top ten charts at number three, so I was delighted, and then it re-entered the charts again when it was re-released on a budget label a few years later.