2016-11-10

Chuckie Egg

Back in the early eighties, when the home computer boom was booming, my parents decided to buy themselves a computer. Following the advice of various computing magazines of the era they ended up with what was supposedly the best of the bunch: the Dragon 32. It featured 32K of RAM, a real keyboard and a Centronics parallel port. It was powered by Bill Gates’ favourite 8-bit CPU, the Motorola 6809. Unfortunately for my parents and their new Dragon, the manufacturer ran into financial troubles and collapsed not long after.

The unusual choice of the 6809 CPU meant very little software was written for or ported to the platform. One of the few games that made it was the BBC and Spectrum classic “Chuckie Egg”. This obscure port (the World of Spectrum doesn’t list it) is by far my favourite version, and it’s the game I spent the most time playing on our Dragon. There has never been a remake of it. Worse, neither the Dreamcast nor the Nintendo DS has a native version of Chuckie Egg. Let’s fix that.

Here’s a beta version of my remake of the Dragon 32 version of Chucky Egg for Nintendo DS and Dreamcast:

A couple of screenshots:

Chuckie Egg Logo Chuckie Egg Game

The game itself is fully playable, but there’s still some polishing to do:

  • Sound on the Dreamcast is misbehaving;
  • The Dreamcast version runs faster than the DS, so some timings are off;
  • Later levels do not have increased numbers of hens or faster moving hens;
  • Hens don’t eat grain;
  • The high score table is not functional (it’s just a bitmap);
  • There’s no “game over” screen;
  • The score/timer/etc display layout and font is all wrong;
  • Remaining lives aren’t displayed;
  • The font in the title screen scroller is wrong.

This is an inexhaustive list of bugs I spotted in the original game while making this:

  • On the first level, climb the largest ladder to the third platform on the right (the start of the staircase). Stand on the ladder just below the top of the floor and jump right. Instead of bouncing off the first step in the staircase, Harry lands inside it. Now press right and Harry will fall through the platform on the right. (The remake fixes this.)

  • On level 7, stand next to the two blocks immediately on the right when the level starts. Face them, hold “right”, and jump. Harry stands in the middle of the upper block. (The remake reproduces this.)

  • Animation frame doesn’t reset when Harry stands on an elevator. (The remake fixes this.)

  • When a new level rolls in the remaining time is set to 999; it immediately jumps to 898 when the level starts. After dying it resets to 899.

  • Harry gets killed if the elevator he is standing on hits the top of the screen, but if he is jumping then he falls through the elevator. (The remake doesn’t kill Harry; he just drops down when the elevator disappears.)

  • There are a bunch of inconsistencies with ladder behavior. Sometimes it is possible to walk from a platform all the way across a ladder; sometimes Harry falls through half-way along the ladder. This looks more like a bug than desired behavior.

  • One of the extra hens on level 3 (at the bottom of the twin ladders) starts one block below where it should do.

Here are some of the differences between the remake and the original:

  • Jump isn’t quite the same.
  • Frame rate is much better.
  • No flickering.
  • Hen patterns aren’t the same (but the Dragon doesn’t match the BBC or ZX, and they don’t match each other, so that’s OK).
  • Duck moves smoothly.
  • Hens move more smoothly.

I think this will be the last remake for a while. This is the list of remakes I’ve managed to complete (more or less) so far:

  • Pong (Blitz Basic/C/C++/Java/Flash; Amiga/Cybiko/GBA/DS)
  • Asteroids (Flash)
  • Mario Bros (Flash)
  • Tetris (Flash)
  • IK+ (Flash)
  • PacMan (Java; Linux)
  • Space War (Java; web applet)
  • Earth Shaker (C++; DS/SDL)
  • Super Foul Egg (C++/Objective-C; DS/SDL/OSX/iOS)
  • BioShock sub game (C++; DS/SDL)
  • Space Invaders (C; DS/SDL/DC)
  • Chuckie Egg (C; DS/SDL/DC)

This is the list of remakes I started but abandoned:

  • World Grand Prix (Flash)
  • Trick or Treat (Java; web applet)
  • Atic Atac (C/C++; Cybiko/DS/SDL)
  • Defender (C/C++; DS)
  • Dan Dare (C; DS/SDL)