Chicken Run Source Code

Edit on Github | Updated: 19th December 2024

Developed by Blitz Games (formerly known as Interactive Studios Limited) in 2000 as a cross platform action adventure game based on the movie with the same name.

Throughout the engine you will find referenced to the acronym isl (Interactive Studios Limited) e.g islfile, islfont etc.

Act (Level) Data

On Dreamcast each act has its own folder each with its own .BFF and .SPT and some containing region specific .SBB/.SBH files. On PC each act also has its own folder plus the addition of .WAB files accompaning the .BFF and .SPT files. On PS1 the layout is completely different, presumably the data is compressed in CRTEST.DAT. it also contains a file called DUMMY which just contains padding 00 bytes.

BFF files (Big file format?)

There is a very helpful comment at the top of the bff_load.c file which explains what BFF files are:

Quickie guide to BFF files:-

 A BFF is, simply, a collection of data segments, prefixed by a TYPE, a SIZE, and an ID (the CRC of a name)
Data of many different types can just be shoved together into one file.
After loading, the program scans through the list, checks the type of each segment, and calls a "link" routine
for that type, which basically fills in any required pointers.

 Then there's a little routine saying "find a bff segment of "such&such type, with this name-CRC"

In the header file it also mentions:

 // All the types of object that you stick into a BFF need to start with a standard header
// which allows the BFF routines to seek out specific objects on request.

// "id" is long something like "PSA0" or "COL1" for PSA and collision data,
// for identifying the TYPE of the block it is.

// "len" is the length of the block, including the header.

// "crc" is the CRC of the name of this specific entry, to distinguish it from any
// other blocks of the same type.

typedef struct BFF_HeaderTag
{
	unsigned long id;
	unsigned long len;
	unsigned long crc;
}BFF_Header;

SPT Files

Used for File streaming, seems to be used for both texture and sound streaming.

CRTEST.DAT (Playstation 1)

This is where the Chicken Run game data is stored on the PS1 version instead of the folder based layout of the PC and Dreamcast. It has a magic number of FLA2, not sure why, did they ever have a FLA1, what does FLA even stand for?

static char FILEIO_CDINDEX[64] = "\\CRTEST.DAT;1"; //	"\\MYGAME.DAT;1"
#define FLA_MAGIC			0x32414c46			// Magic number 'FLA2' INTEL

Games Referenced in the Source code

Developers tend to reuse the same engine or parts of the same engine for multiple games across a wide range of platforms (one of the beenfits of writing in cross-patform C), which means there are other games that will share many of the same source files used in chicken run. Here is a list of games that have been referenced in the source code:

• Glover
• Action Man 2
• Frogger 2

Dreamcast Engine

Most of the dreamcast specific code has a DCK_ prefix, presumable short for Dreamcast Katana (Katana was the code name for the dreamcast). Some example:

• DCK_System
• DCK_Texture

Presumably there were versions of this code with N64 and PS1 prefix used at ISL but they weren’t released with this source code unfortunetly. As most of the game code is cross platform but these files contain the very platform specific code for the Dreamcast.

Compiling for Playstation 1 with PSYQ

So although it was originally compiled for PS1, all the sourcecode has been modified for the dreamcast version so it will need some modifications in order to compile for the playstation.

The following files won’t compile to PS1 without modification:

• types.c

However the root/cr/source folder contails a makefile.mak which is for psyq and build the PS1 version.

There are a 2 linker files crtest.lnk and crdemo.lnk which are for the PS1 development tool PSYLINK.EXE you can find out more about there files here: http://www.retroreversing.com/ps1-psylink

These files are vital for piecing together the PS1 source code as it contains the exact specifications for the object files and libraries that were linked in to get the final and demo executables for the playstation.

Missing Files

As with most leaked source code there are some missing files these are:

• shinobi.h (Dreamcast SDK)
• sg_syhw.h (Dreamcast SDK)
• km*.h (Dreamcast SDK)

C Game Source Code

Some of the source code for the game Chicken Run has been available to the internet as part of a “Dreamcast source code” bundle. After extracting the archive we are presented with two folders, “simple model shell” and “cr”.

Presumably cr stands for chicken run and the simple model shell is a tool to display some of the 3D models as they would appear in the game engine.

Simple Model Shell

This tool would have been very useful for artists when exporting their models from their modelling software such as 3ds max or maya, as it will show what optimizations need to be made to the model.

CR (Chicken run source)

We actually have multiple versions of the chicken run source code:

• the main cr folder
• source folder under cr (ps1 makefile so guessing ps1)
• “Copy of Source” folder under cr (?)

This was very common before good version control software such as git came along, so developers would work in seperate folders and merge changes, or keep different console ports in different folders.

The main files in cr are:

Data Structures

Playstation 1

PS1 Gameshark cheats

Game Credits

• Fred Williams (Lead Programmer) - https://twitter.com/RFredW

  • // I'll do these things for platforms, with a view to copying 'em into the main collision code
    // when it's free. Luv, Fred.
    

• Tom Drummond (Programmer)
• David Harries (Programmer) - https://www.linkedin.com/in/david-harries-92a56213/
• Barry Peterson (Programmer)
• Chris Wilson (Programmer)
• James Steele (Tools Programming) - https://www.linkedin.com/in/james-steele-0a62791/
  • c // Since Fred insits on being such a clever bugger and using in-line assembler, this file contains a load of macros so that the custom.c, custom2.c and map_draw.c compile and work on the PC as well as the PSX without me having to write a whole load of PC draw routines. // James Steele
• Chris Wilson (Tools Programming)
  • ` /* Curtains.c - by Chris Wilson It’s curtains for you, my lad!*/ `
• Ian Bird (Additional Programming) - https://www.linkedin.com/in/ian-bird-19358780/
• Steve Bond (Additional Programming) - https://www.linkedin.com/in/steve-bond-b21ba9/
• Scott Lamb (Additional Programming) - https://www.linkedin.com/in/scottjameslamb/ (SL: in comments)
• Andy Sidwell (Additional Programming)
• John Whigham (Additional Programming) - https://www.linkedin.com/in/john-whigham-b8524834/
• Richard Hackett (Compression Technology) - https://www.linkedin.com/in/richard-hackett-4324531

Also thanks to Phillip and Andrew Oliver who founded Blitz Games - http://www.olivertwins.com

Sources