A little more information about a few of the dozens of ZX Spectrum games I've developed over the years. More will follow as each game hits its tenth anniversary.
Written in November 1989, this fairly clunky game took approximately four weeks to write, from start to finish. The sprites were designed with my own custom sprite designer program (later released as PD) and were all plain white to cut down on attribute clash. This was the first time I had incorporated 128K music and sound effects into a game, having taught myself the basics of the AY-3-8912 sound chip the preceding summer, and the tune itself had simply been lifted from an old BASIC magazine listing and converted with a Hz table. Note the reference to an absence of music in the scrolling text - it was written before I decided to attempt the music. Designing the 40 levels seemed to take the longest amount of time, and was a part of the development of any game that I absolutely detested. Nonetheless Richard Eddy loved it, and it was published on the Crash covertape for February 1990.
Egghead to the Rescue (1990)
For the sequel, written early the following year, I decided on a new look. Egghead had a very early 80's look about it, and I wanted something altogether slicker. For the first time all the graphics were designed using an art package (The Artist II) then POKEd into memory using a simple BASIC program, a technique I employed many times after. I discovered a better method of animating the main character, there being 8 frames of animation rather than the 4 of the original, and wrote a new sprite driver. The sprites now also passed behind the scenery with the help of a dummy mask screen, a technique devised to eliminate colour clash. Unfortunately, the sprite routine wasn't quite up to the job and on one or two screens the music would slow down and speed up as the sprites were rotated into position before being applied to the screen, although the effect was almost imperceptible. The irritating music was originally going to be a simple composition of my own, consisting of 128 musical notes. At the last minute I decided my musical ability really wasn't up to much and replaced it with a version of the French Can-Can. Alas, this really required 144 notes but by then my buffer had been set in stone, which meant a slightly abridged version had to be used. One other point worth mentioning is the sheer number of letters I received once the game had appeared on the December 1990 Crash Powertape. People loved it, and put pen to paper in large numbers to tell me so. A third game - Egghead In Space - was initially considered but subsequently dropped in favour of other projects. It would take another twelve years for the series to be continued.
Shove Off! (1990)
In 1989 I had purchased an Amiga, and one of the games I most enjoyed playing was a version of the Japanese warehouse game, Soko-Ban. This was my Spectrum version, and it took 5 months to produce, mostly because I had to design and test 100 different levels. My third sprite driver was much faster than itsancestors, but still not quite fast enough as the main sprite flickers slightly at the top of the screen. Nice high score name entry routine, mind you. GTi software, a tiny Devon software house, paid me 100 pounds for the game - plus the return train ticket to Newton Abbot to sign the contract, a 4 hour journey. Shove Off! was originally going to be called "Push Over" until Ocean released a game of their own with that title. Cheat mode: get a high score, then enter your name as "EGGHEAD." - don't forget the full stop.
I have to be honest and confess to not really liking this program, although it seemed like a good idea at the time. Published by YS in 1993, Pipework was a 26 screen puzzle game loosely based on Pipemania with one or two of my own ideas thrown in for good measure. It was written in Z80 assembler, with a simple screen editor bolted on as an afterthought. Curiously, The screen editor was written in BASIC to save time, then compiled to machine code using version 1.0 of my simple BASIC compiler, Turbo. The only other feature of note was the spinning logo; this was achieved with a pre-calculated sine table, a subroutine later to be adapted and used on Megablast. Cheat mode: type TYPHOO TEA or PG TIPS on the menu screen, then press ENTER. One of these will activate the cheat mode, the other deactivates it although I can't remember which one is which!
Haunted House (1991)
There was plenty of attention to detail in my next platform game. The torches burn, the fountain in the garden works, and just watch the eyes of the portraits follow you across the room. The main character Izzy even tapped his foot while the game was paused. Some of the sprites from the Egghead games were re-used, along with a few new ones, and the liquid dripping from the ceiling was a pleasing effect. Don't ask me what it was supposed to be, I never really worked it out myself, but somehow you just knew it wasn't water... uurgh! Although there were 40 rooms - 8 more than Egghead 2 - the screens were slightly smaller to accommodate the time and energy bars. The enlarged font meant I could have the letters dripping, and the routine was re-used in a later game (Megablast) with another font. Originally the game was accepted for publication by Beyond Belief software, although after several months of hearing nothing, no contracts had been signed and I wasn't getting any answers over the telephone. I eventually gave up and sent the game to Your Sinclair. Exactly why they decided to refer to the main character as Derek Cracklybrownpaper is beyond me, but then YS always were a bit hatstand. Many years later I read that Beyond Belief did have plans for this game, to change the sprite for the central character and release it as 'The Adventures of W. Scribo'. This was certainly news to me. Besides, I prefer its existing title.
Super Fruit Machine (1991)
A weekend of wandering around the amusement arcades of Ingoldmells provided the inspiration for this simulation, oddly enough the only one of my games to be rejected by Your Sinclair. Little did I realise that just over a decade later I would be programming fruit machines for real. Sinclair User eventually published this in November 1992, the same month Haunted House appeared on the YS tape, although this was definitely the weaker effort of the two. The display routines used on the scrolling reels were quite flexible, and were subsequently adapted to form the basic scrolling window on Megablast - my next project. Attribute clash was avoided by placing the symbols 8 pixels apart, an old trick but one that worked.
Another game which was initially accepted by Beyond Belief, Megablast started life with a working title of Voidrunner, until someone pointed out that Jeff Minter had already written a game with that title. There were 16 levels, all of which were compressed, only my own boredom prevented there being any more.Some likened the game to Uridium, although its true ancestor was the Amiga game Goldrunner II, albeit with a number of changes. The real reason for writing a vertically scrolling game was speed: there was no need to laboriously shift four thousand-odd bytes left or right, in fact the dummy background screen was designed in a wrap-around fashion, all that was required to scroll it up or down was to change the 2 bytes that pointed to the address of the top of this buffer. Once the sprites were applied the whole thing was dumped to the window on the screen using twenty or so LDI instructions in a loop. The music was really only an afterthought which was bolted on before it was submitted to Your Sinclair, and was a composition of my own produced using AY Tracker - a decent attempt at a music program at my fifth or sixth attempt and later released as PD. Megablast was designed to be as much of a challenge to the hacker as the player; rather than use the standard DEC (HL) instruction to reduce the number of lives I opted instead for XOR A: CPL: ADD A,(HL); a bizarre combination of mnemonics designed to throw hackers off the scent, a ruse that ultimately failed as an infinite lives POKE can be found on the web. Cheat mode:press P to pause the game, hold down symbol shift then press B.
Having written a vertically scrolling shoot-em-up in Megablast, the next avenue to explore was a horizontal affair, and for this I selected the arcade classic Scramble as my model. Like Megablast, the idea of the game was to rescue hostages, although this time the stranded astronauts waved their arms to attract attention, a feature which was easy to implement as all the sprites were pre-shifted to save processor time, a must when implementing a horizontal scroll. So precious was CPU time that the scrolling routine consisted of hundreds of consecutive pairs of instructions; RL (HL): DEC L. Every 256 iterations DEC L was replaced by DEC HL, decrementing an 8 bit register instead of a 16 bit register pair saves a few clock cycles. By now we were in to the spring of 1993, and no software houses were accepting Spectrum games. The game was duly despatched to Your Sinclair, and when I received a telephone call from the magazine assumed quite naturally that it was merely to confirm the game was to be accepted. Sadly this was not the case, the publication was closing and the final issue was due to be "put to bed" in a couple of days time. With no time to lose I put together a compilation of ten games, including Squamble,and sent it in for review without having designed an inlay or even consider its title. I need not have worried. Before the final edition had even reached my local newsagent cheques were arriving on my doormat for a compilation entitled "The Bumper Boogie Pack". Oh dear, YS strikes again. The title stuck, but allow me to place on record the fact that it wasn't of my own making!
If anyone were ever to invent a time machine there might be a multitude ofapplications. Just imagine being able to discover the cause of the extinction of the dinosaurs, or witness the birth of the universe. Personally, I'd take a copy of Gloopback to 1982, sell it to a big software house and retire on the royalties! Certainly one of my favourites, very few copies of this game were ever sold and it looked destined for obscurity until Simon Ullyatt of Cronosoft arrived on the scene in 2003. A cross between Monster Business and Bubble Bobble, it featured Izzy, the main character from Haunted House. The objective was to leap around the platforms blowing bubbles at an assortment of mutants in order to inflate them. After a few hits each would become so bloated that it floated up to the ceiling where it could do no harm. Started in March 1994, I didn't get time to finish it until September, although this was hardly surprising as the graphics and presentation were quite polished, even down to the "mug of tea" energy indicator, an idea inspired by the roast chicken in Ultimate's Atic Atac. Sixteen frames of animation were used for Izzy, who again passed behind on-screen objects, although this time a second dummy mask screen was required for the attributes because the sprites were individually coloured. A third game in the series, Izzy Wizzy, was written in 2006.
Dead or Alive (1995)
Being a big fan of the coin-op Gunsmoke I had always been bitterly disappointed with the official Spectrum version and this my answer. Biased I may be, but I think my version plays better even if it does suffer from a lack of levels. Dead or Alive was the first of my games where the bulk of the development was done using a Z80 cross assembler for the PC and an emulator, although the graphics were still designed on the original hardware. Unfortunately I had no easy way of porting the code to the Spectrum itself so once development was complete I printed out the few thousand lines of the assembler listing and laboriously typed the whole thing into a Spectrum assembler, a painful process but still faster than developing the whole thing on the target machine. Since then, all my Spectrum games have been developed on a PC.
Egghead in Space (2002)
While I continued to develop Spectrum software after 1995, it took a while - and the emergence of the internet - to encourage me to develop a new game from scratch and publish it. Egghead in Space was the result, the third in the series and an unintentional step in the direction of the Monty Mole games. At the time of release in December 2002, very few Spectrum games were being released, save for the occasional Jetset Willy remake. This was something new. I was a little out of practice with my Spectrum programming and my library of routines was on cassette tape, meaning I'd have to write everything from scratch on the PC I used to develop the game. Worth maybe six and a half out of ten, and still fun to play. Egghead 3's major claim to fame is as Cronosoft's first game, early in 2003. The splendid loading screen was drawn by Tommy Pereira.
Rough Justice (2003)
Work for this variation on Cybernoid started out in 1995. Sadly, the magazines had closed and nobody seemed interested in buying new Spectrum games so the project was shelved although I returned to it here and then over the coming years. The levels were initially randomly generated by the Spectrum itself and then manually edited to remove unfairly placed enemies etc and make the game a little more forgiving. Tommy Pereira again provided the loading screen and I think I'm correct in saying that this was the first of my games for which somebody else provided the music. A round of applause goes to Yerzmyey who provided the first of many fantastic songs for this game.
Amusement Park 4000 (2003)
If memory serves, there were 63 entries to the 2003 minigame competition. The rules were relatively simple: to write a game for an old platform in just 1K or 4K of memory. Rather than produce a Pac-Man or Space Invaders variant I set about this somewhat more ambitious project for the 4K category: a Theme Park clone. The basics were all there - guests would come into the park, wander around, queue up for rides (which would flash when in operation) and then get off and go and do something else. Spending money on research would make new rides or features available although memory restricted the number somewhat; if I were writing this game today I might be able to squeeze more in. Nevertheless, it proved to be very popular and people were playing it for hours on end, some well into the night, by all accounts. Amusement Park 4000 eventually took the silver joystick, finishing just behind Robin Harbron's C64 Minima. The following year it was extended with more rides and attractions and published by Cronosoft under the title Fun Park. If you haven't played it before, it's worth downloading from World of Spectrum. You'll be surprised how much fun you can have in 4K of code.