Conversion Kings: Lemmings
Lemmings was one of the biggest games ever for the Commodore Amiga, so how would an undergraduate university student take on this behemoth and convert it to the ZX Spectrum? Retro Gamer spoke to coder Jonathan Dye to find out
Discover how Jonathan Dye crammed a hit Amiga game into the ZX Spectrum
Converting an ambitious title like Lemmings to the ZX Spectrum would be a massive task for any developer. Jonathan Dye was the coder up to the task, but he had to fit his university studies around the development. Though if Jon had to blame anyone for the mountain of work, he’d have to blame himself. After all, it was Jon that took the idea to the head of DMA at the time (Dave Jones) and attempted to convince him it could work. Jon begins, “I started working for DMA in the summer of 1990 which was at the end of my first year at university. I had proposed to Dave that we did a conversion of Lemmings to the Spectrum. It’s fair to say he was very sceptical based on the fact that the Spectrum was 8-bit and may not have the processing power or memory, plus the limitations around colour and sound. He asked me to develop a working model to prove that it was feasible before he would sign-off on a full-blown conversion.”
So, what are the first steps in getting a working model for a game conversion? This is usually where a coder would look to transfer code and graphics from the original game, but unfortunately for Jon this was not possible with Lemmings; due to the difference in both specs and
screen size, the game had to be rebuilt from the ground up. As Jon explains, “The Spectrum screen is set differently to the Amiga, which means a smaller game space, and that meant that the original levels would need to be junked and a whole new set of levels needed to be designed from scratch.” He continues, “The main challenge was that it wasn’t really a conversion as such, but a complete rewrite of the original game; it was more an exercise in reverse-engineering the original game onto the ZX Spectrum based on its general look and feel. A lot of things had to be rewritten to be faster or done in a different way to the way the coding was approached in the originals.”
After a long time spent redesigning the levels, next Jon had to get the critters onto the screen, but how do you make a 16-bit game run smoothly on an 8-bit counterpart? “In order to make the game as smooth as possible, there is a second copy of the screen held in the memory where the Lemmings are added in the various stages of their animations according to the role they play (digger, climber, etc),” Jon remembers. “After testing, it became apparent that from about 30-plus Lemmings on the screen, the game slowed down to the point where it wasn’t very playable. That amount was a lot less than the original, but enough to work with to keep it a viable conversion.”
Jon’s hard work on the game paid off and eventually saw his efforts produce the goods. As Jon recalls, “I still remember the first time I saw Lemmings march across the screen on a landscape on the Spectrum and I think once Dave saw that, he knew that the game was viable. To be honest I think he and the producers were quite surprised at how smooth and fast it was. It had taken a lot of attempts to try different options to get it to be that fast. This meant it was going to be possible to see Lemmings on the Spectrum, the next thing to look at would be how to make it work on the Spectrum given its limitations.”
Lemmings was certainly very appealing on the Amiga – multicoloured, nicely animated, speech and the very familiar theme music for each level. This would take some replicating and in some areas, inevitably, omissions would have to made. How would this be approached? Jon says, “It was clear from the beginning that the levels would need to be in monochrome as the limitations on colour meant that it would not be possible to do otherwise. That meant the Lemmings would effectively be in silhouette only because they are drawn so finely, even when so small, that it’s clear what they are doing. With regards to sound: at first I thought of just simply having none as it’s a distraction and takes up some processing power. However, the rubbish old songs had become iconic in the original, so I think there was some pressure to include tunes. The tunes actually turned out to be not too bad given the Spectrum’s limited sound capability. Though personally, I think they were fairly annoying!”
Despite the machine’s limitations, the Lemmings have the full range of activities which the original game had, though the other notable difference is the lack of mouse input, which is what the original
game was designed for. Not a lot could be done about that, given that it was not possible on the Spectrum, so the crosshairs were moved with the keyboard or joystick methods that the machine offered. Jon says of this that the movement can be a bit “clunky” when compared to playing with a mouse, but once you get the hang of it it’s “not too bad” – an assessment which sounds about right to us.
Lemmings was a massive achievement for the Speccy and a real love affair for Jon. Not only was he working on such a huge project, but also trying to earn a degree simultaneously: ploughing all of his spare hours into working on the game during term time and working out of DMA studios during the holidays. The whole process took around 18 months, which shows just how big a job this was for the young coder. After all that time and effort, how does
Jon feel about his conversion? “I was very happy and proud of the finished product but I was also mainly relieved. There were times during the coding that I didn’t believe I was going to get it finished or that the quality simply wouldn’t be good enough and it would get pulled. But I also think that the final product definitely can sit firmly alongside the other Lemmings conversions with its head held high – and it also proved to the publishers that 8-bit conversions of Lemmings were possible.”