@FPAdventuresBot is a Twitter account that regularly posts screenshots from first-person, point-and-click adventure games. Images are randomly selected from a pool, pre-extracted from original game data files. The bot source code is available on GitHub:

https://github.com/greg-kennedy/FPAdventuresBot

It uses Twitter::API to manage file uploads and posting to Twitter. For some games, I have written custom tools to extract images. Source code for these is in the tools/ subdirectory. There are also some audit scripts in the main folder to find duplicate images or solid-color images. These use Image::PNG::Libpng for working with PNG images.

The account currently posts images from the following games:

Secret of Evermore is a game for the Super Nintendo released in 1995. It continues to be a somewhat controversial title in the otherwise spotless Squaresoft SNES library… but I like it, and my wife plays it as a “comfort game” whenever she is feeling sick.

IPS is an antiquated binary patch file format, used to provide a “diff” of raw bytes that should be applied over an existing file. IPS patches for SNES games are widespread, and often do things like enable cheats, alter graphics, translate text, etc. In some cases, people have found bugs or glitches in the original code, and release an IPS patch to fix it. Often these are found from the work of speedrunners, who spot a glitch and exploit it to break the game in some way. The SNES hackers then identify the code problem behind the bug, and patch the raw binary code to close the hole. There’s a whole black art to crafting binary bugfixes – the space for a fix is severely limited, and if the new code is too big you have to find additional unused code area elsewhere to jump into (or optimize a different routine to make some free space!)

For some games, more than one bugfix patch is available. Managing these with the ubiquitous LunarIPS tool is a pain – you have to generate a bunch of intermediate ROMs, and the patches may conflict / overwrite one another without indication of the problem. There are better IPS patchers around, but I didn’t want to go on a research quest to find one. Besides, IPS is a pretty simple format – why not just write my own patcher?

I wanted a way to take a binary file, apply a complete “patch set” to it, and return the resulting bin. I wanted it to check for conflicts in patches, and give a descriptive message of which exact patches were colliding. And then I didn’t want to just serve up a cooked file, for copyright and maintainability reasons. “XYZ (Bugfixed)” hacks are too frequently outdated, as new patches are released. So I put a simple PHP frontend before it and a folder full of patches server-side.

The tool is here: https://greg-kennedy.com/SecretOfEvermore/

Users can upload a file. If the SHA-1 matches, it gets patched and they download the fixed version. This tool is for Secret of Evermore, with all the patches (i.e. “hard work”) done by Assassin17.

I may stand up sites for other games as I run across them, or merge these into a single “bugfixer” tool if it gets too out of control.

The patch.pl script follows.
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Before there was World of Warcraft, there was Everquest. I never played it but I had a buddy in college who did: he talked about how amazing the MMO genre was, with all its social aspects, technical quirks, and just plain cool experiences.

Naturally it inspired me to make my own clone. In Visual Basic. With 2d graphics and piping everything through the Winsock .ocx control. Full of programmer art made with a pirated copy of Bryce 3d.

Ah, the wide-eyed days of a young programmer in a rapidly expanding genre. It’s like I was playing out every cliche of the Gamedev.net newbie at once. The one thing I had going for me, though, was a thorough understanding of the impossibility of such a project – and a sense of humor about it all. For example, I often joked that the only enemies were going to be Gelatinous Cubes, because that would be easy to render. I once wrapped a photo of my roommate’s face on a sphere to use for a hideous player character head. And so on. Eventually I got about as far as a character select screen, with a couple songs, before giving up and moving on to something else.

Unlike SlugFest, this is one that isn’t ever going to get off the ground. If anyone is interested in the art and music resources, you can have them: hereby released into the Public Domain.

This isn’t my only brush with the MMO genre. Later on some friends and I tried another take on it (“Draconis”) as the U of A Game Dev club project – with a result somewhat similar to The Mana World, and it once held up to five players online simultaneously. The real killer for these kind of games is the sheer amount of content required. Though Draconis worked technically, all the content in the world was viewable at first login. Hardly a compelling MMO experience.

Download GregerQuest Resources: .ZIP file, 1.9mb.

Auditing ROM collections has been made much simpler over the years thanks to concerted efforts of many cartridge purchasers, dumpers, cataloguers, and coders.  Using a combination of RomCenter (or ClrMamePro) and a No-Intro .Dat file, one can quickly fix an entire collection in one go: repairing names, verifying regions, checking for problem ROMs, producing have-lists, etc etc.

NES roms throw a particular curveball because they carry a 16-byte header with a little info about the board within the cart.  Emulators need this info, but it isn’t verified by No-Intro since it’s not part of any real dump.  As a result iNES headers remain missing, incorrect, or filled with crap data.  A new repair tool is needed.

ines-fix.py is a Python script which can repair defunct iNES headers using an external cart database.  It does this by extracting the data portion from the file, calculating a crc32, looking for the crc the xml file, and then rebuilding a header based on that info.  If the old and new headers differ, the file is overwritten with a fixed version.

Be careful with this tool: it’s sort of a blunt object, and may trash your rom collection if not used carefully.  Make backups.  In particular it writes only iNES v1 headers, expecting emulators to cope with the shortcomings of this format.

Output samples:
-> No change to existing header

CRC check: 4318A2F8
Found CRC match: Barker Bill's Trick Shooting
*** Header unchanged: not writing replacement file.
----------------------------------------------------

-> Adding a battery

CRC check: 1F6EA423
Found CRC match: Baseball Simulator 1.000
*** HEADER UPDATED ***
oldHeader: 4e45531a081010000000000000000000
newHeader: 4e45531a081012000000000000000000
All done.  Wrote new file roms/Baseball Simulator 1.000 (USA).nes

-> Correcting a mapper, vertical mirroring, and removing “DiskDude!”

CRC check: 9BDE3267
Found CRC match: Adventures of Dino Riki
*** HEADER UPDATED ***
oldHeader: 4e45531a0204004469736b4475646521
newHeader: 4e45531a020431000000000000000000
All done.  Wrote new file roms/Adventures of Dino Riki (USA).nes
----------------------------------------------------

-> Standardizing on “horizontal mirroring”

CRC check: 3ECA3DDA
Found CRC match: Bases Loaded 3, Ryne Sandberg Plays
*** HEADER UPDATED ***
oldHeader: 4e45531a101041000000000000000000
newHeader: 4e45531a101040000000000000000000
All done.  Wrote new file roms/Bases Loaded 3 (USA).nes
----------------------------------------------------

-> Adding a missing header

CRC check: 50CCC8ED
Found CRC match: Battleship
*** HEADER UPDATED ***
oldHeader:
newHeader: 4e45531a020430000000000000000000
All done.  Wrote new file roms/Battleship (USA).nes
----------------------------------------------------

Here’s the script:

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