Resurrection, Lemmings Style

Posted October 22nd, 2011 in Lemmings, Projects by David

I’m not dead, and neither is the project!

After a month off to deal with life in Meat-Space, I finally found a “round toit” and resumed work on Lemmings.

A brief update of where things are currently at:

  • I’ve ripped out everything, and started fresh
  • Lots of focus on structures and proper organisation of data
  • Some important decisions have been made

I’ve established some definitive sizes for various bits of data (e.g. the raw and compressed terrain data) and cracked some other structures of the original game (such as ODDTABLE.DAT)

Some important decisions include:

  • There’s no possible way to include everything on a single disk, so I’ve given up trying
  • I hope to fit the entire ‘fun’ level series onto the first disk, but…
  • … I’m not going to do so before moving on!

Basically, I’m going to pick some levels and use those both for coding and for demonstration purposes.

Levels are being chosen based upon their contents, rather than their ‘fun-factor’ – it’s more important that I get to test all of the terrain sets, all of the objects / traps and all of the lemmings abilities – eventually. For now, I’m narrowing the focus to getting some core code working, such as object rendering, basic lemmings, and functional entrances/exits.

I’ve chosen the following to start with, based around the “Dirt” terrain set

1. Just Dig (Fun, Level 1)

  • It’s traditional, in that every person who’s ever played Lemmings has completed this level
  • It’s simple – an entrance object, an exit object, and a single animated non-interactive object
  • Only one skill is needed to complete it, which reduces my coding time
2. Here’s One I Prepared Earlier (Tricky, Level 4)
  • It’ll let me test the one-way arrows
  • Lots of water will help test the speed of non-interactive animated object rendering
  • Has non-interactive animated objects being rendered both in front and behind terrain
  • Good for testing ‘steel areas’, which protect terrain from being bashed, mined, bombed or dug
So, multi-level support, here we come!

Original Lemmings level file format specs

Posted October 4th, 2011 in Lemmings, Random Stuff by David

Just a quick note to say I’ve posted the documentation for the Lemmings original DOS level file format, which is also used by the Windows 95 version.

You can read it here

Note that the DOS version of Lemmings compresses it’s level data, and you’ll need to uncompress the data using something like Lemmix or LemEdit first!

Real life strikes

Posted September 28th, 2011 in Random Stuff by David

Just a brief note – I’ve been stuck with Real-Life mode for the last week or so, which has made finding time for Lemmings difficult.

In what little spare time I’ve found, I’ve been working away at some refactoring and documentation.

I’m hoping to get something new and impressive up soon!

How to compile GCC for the 6809 processor (gcc6809)

Posted September 22nd, 2011 in Random Stuff by David

William Astle has been hard at work bringing gcc6809 in line with recent gcc releases, namely 4.6.1

In this quick walk-through, I’ll show you step-by-step how to patch and compile gcc-4.6.1 with gcc6809lw on Linux, enabling you to cross-compile binaries for the 6809 processor.
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Lemmings: CoCo 3 vs. Amiga, an early comparison

Posted September 21st, 2011 in Lemmings, Projects by David

They say, “An image is worth a thousand words”, so here’s an essay in picture form.

I’ve been slightly modifying the palette for the ‘Hell’ set since I last posted, eliminating the jarring ‘bright white’ and going with a more subtle salmon colour as a substitute for light-grey – I think it works a lot better.
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This project has gone to Hell

Posted September 20th, 2011 in Lemmings by David

.. but in a good way!

Here are some screen-shots from the new ‘Hell’ terrain set, which I’ve just extracted from the “Original DOS Release” source files.

Below is also a comparison screen-shot from the Amiga release, so you can see what the CoCo3 is up against!
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Major, Major Revelation

Posted September 18th, 2011 in Lemmings by David

A few major discoveries regarding the internal data structures used by the DOS Lemmings release – specifically the graphics storage – has provided some much-needed encouragement!

Update: Some things weren’t quite as they first appeared – read on to find out what’s changed!
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Decoding Lemmings: The Hunt For Data

Posted September 18th, 2011 in Lemmings by David

During the early stages of planning this project, I hunted all over the web for any and all information I could find. I needed to know everything, including:

  • What were the original sprites? How can I get them?
  • How were the original levels constructed? What graphics were used?
  • How did the game keep track of what was happening to each lemming?

There was a distinct lack of information available, so I decided to cheat a little, and look for source code instead.
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DRPack – Why my compression sucks

Posted September 18th, 2011 in DRPack, Projects by David

After bashing my skull against PHP and forcing it to play nice with 8-bit values, and implementing a fancy-schmancy “state machine”, and even getting all ‘posty’ and writing about it in my blog, there’s been a dramatic development:

My compression sucks.

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Tangential Developments / Compression

Posted September 17th, 2011 in DRPack, Lemmings, Projects by David

One of the more frustrating things I’ve found about building such a large project is the sheer volume of ground-work needed to get anywhere.

In getting to where development currently sits, I’ve had to investigate and learn a bunch of “side topics”, which…

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