Extracting information from Creatures 1 PhotoAlbum files (And uncovering a 20 years old 2 pixel bug :)

In the last article, we've seen how to manually use the "dde: pict" CAOS command to take picture of our Norns the way the Owner's kit does it.

When doing it the usual way through the Owner's kit, all pictures are saved in individual photo album files for each Norn.
In this article I will show you all you need to know to extract all information from those file : timestamps, comments, and obviously, the picture data.

Repairing and understanding the lost "dde: pict" command (Taking photos of C1 Norns)

One promising nugget in the Creatures 1 CAOS reference, is the "dde: pict" command.

According to the documentation,

 Unfortunately, as many other things this command not only lacks critical bits of explanation but is also inherently broken (at least considering the above definition) and when used produces less than stellar results:

It's a shame we can't use this functionality in our own tools to take pictures as the Owner's kit does.
Or can't we ?

One of the main motives behind the site being uncovering such lost knowledge and abilities of the ancient Shee, come with me and find out how to understand and ultimately take advantage of this lost command.

Reversing the C1 .exp file format part 1 (General layout and extracting the genome)

It's been all those years, and despite a lot of talented persons having contributed to making Creatures tools or documenting the game various features, there still isn't any available description of the .exp file formant anywhere as we're nearing 2015.

The .exp files are the format in which creatures are exported or imported from and to the game.

Obviously, they contain about anything one could need to know about a given Norn, and exploiting them for writing custom tools might allow for a lot of interesting options such as exporting a critically ill norn, performing offline surgery on the file, and reimporting it into the game.

This would allow curing a couple otherwise fatal issues since the ingame mechanics don't provide any means of removing a given chemical from a creature bloodstream or reinvigorating degraded C2 organs.
(See the case of C2 grendels being oversensitive to cyanide poisoning because they lack the chemical reaction genes that would allow them to lower their cyanide levels)

In this series of articles, I will describe the process of reverse engineering the C1 (and later C2) .exp file format so any programmer out there can use the information to implement .exp file manipulating programs.

The first articles of the series will show the process followed so more people can learn "how it's done" and maybe later take on reversing other undocumented game file formats.
Hopefully, if enough information can be gathered about the format, a final article will sum everything up into the cleanest and most complete description possible.

For this first article, we will analyse the general file layout, and learn how to extract a working genome file from an .exp file.

Let's dive into binary DNA !

Parsing Creatures 1 .spr files (Extracting/Manipulating any of the game's graphics)

In a previous article I showed how to read Creatures 2 .s16 files to extract any of the game image data.
In this obvious follow up I will show you how to read out Creatures 1.spr files for the same result.

The Creatures 1 .spr file format is only marginally harder to parse than the .s16 format.
This is because the .spr files do not directly contain color information for each pixel, but rather an index number, to be used as a lookup index inside an external palette file to get the actual color data.
 
Thankfully, Python magic can once again save us most of the hard work and makes extracting an manipulating C1 images files a breeze.

Connecting to the Creatures DDE interface from python

We've recently seen how easy it is to connect to the C1 and C2 DDE interfaces using VB.

This time we will show how easy it is to connect to those interfaces using python, which will prove useful in upcoming articles.

Connecting to a DDE server from inside python is can be a quick and easy process.
The hardest part is in acquiring the correct modules to do so, (which can be a real pain if you take it from the wrong side), there are also a couple specifics that make debugging the first DDE connections unreliable.
Fortunately I've sorted those perks out for you,and will show you the single quickest and easy way to connect to the Creatures 1 and 2 DDE interface from python.

Parsing Creatures 2 .S16 files (Extracting/Manipulating any of the game's graphics).

"Back then" few easy image manipulation libraries were available, making the extraction of game image data an intricate process (that most creature fans/developers tackled in an easy but not very user friendly way as we will expose).Nowadays things got easier.

In this post I will explain the creatures 2 .s16 file format, and show you how you can now very easily extract any picture from the game using python.
Not only that but we can also harness the power of modern image manipulation libraries to convert the game sprites to any file format we like contrary to most legacy tools only proposing to export images as BMP's and letting us do the conversion work manually.

Connecting to the Game: accessing the DDE interface with 3 lines of code. (Tutorial)

We've been studying a lot of stuff lately, most of it involving running CAOS commands against C1 and C2 games.
C3 has a convenient built-in CAOS console, and various third party tools also propose that feature for C1 and C2.

But how would you go about implementing this kind of connectivity inside your own programs?
The simplest way to connect to a running C1 or C2 game is through the DDE interface (Dynamic Data Exchange). Also it REALLY is simple even if you barely know anything about programming, so this might be worth checking out.If you never programmed anything and don't have any development tools handy, you could initiate a DDE connection even from inside an Excel macro using VBA.Also the C1 and C2 DDE interfaces being strictly identical, you'll be writing code only once, and be able to use it in both games right now, without any change.

By sending the game some basic CAOS commands and reading their results you can reproduce all of the game functionalities and then some more: reading a Norn's needs and chemicals levels in realtime, selecting Norns and Grendels, carrying them, monitoring their brains,etc...

This time I show you a very quick overview to get you started in pumping CAOS in and out the C1 and C2 games.More advanced use cases or details will come in futher posts.