The Ur-Quan Masters Discussion Forum

Hello again, everyone!

I know there are a couple of saved game editors around, but I haven't found a way to edit the melnorme credits. Does anyone know how this can be done?

Also, does anyone have any info about what offsets contain which settings when using a hex editor? I checked the save.c file, but I couldn't figure out how to translate this into the offset of a particular value.

Thanks!

The saved games are compressed to save disk space, making it very hard to hex edit most of the game state. The easiest solution is probably to modify the save or load code.

Annoyingly, the Melnorme credits are also stored in uncompressed form (used to display the summary of the game state in the load menu), but this is not the version used by the game.

If you are that interested in cheating the game, you can try memory editors, like scanmem for Linux or ArtMoney for Windows.
I know it works, cause I did it myself :)
No weird searches like multiples or the -1 stuff, just the exact number on display in the cargo menu.

Thanks.

I tried a couple of memory editors while talking to a Melnorme ship. When I search for the number of credits in my inventory, it comes up with hundreds of hits on every integer/float type. I did have a little bit of fun manipulating the dialogue in real time, though :) Searching for strings seems to be a lot easier than numbers. I did find a string value for MCredit, but not MCreditHi or MCreditLo. Unfortunately, I don't know how to edit a variable directly from memory.

Not credits - bioforms are the way to go.

I made an editor you can modify the credits with here:
http://forum.uqm.stack.nl/index.php?topic=4890.0

I also did a save game editor (http://forum.uqm.stack.nl/index.php?topic=4672.0) previously, I can take a look at what offsets it uses and post them. Stand by.

The credits aren't stored in a straight forward fashion in the memory. They way my memory editor reads them is to first read 4 bytes at a specific offset. Then it uses that data, plus an offset, as the next memory location to read to find the actual credits.

It basically finds the location using a pointer. A program called "Cheat Engine" has good support for this.

So it reads 4 bytes from this new location. Then it right shifts the data by 3 (eliminating the last 3 bits). Finally it zeros the two leftmost bytes. And the resulting data is the credits.

Writing the credits is also tricky because you have to change only specific bits in the 4 bytes of credit data.

Ok, these are the save game offsets you can write to and have the game accept the changes (changes to credits and lander stats etc. are ignored):

If you want to know the details, look at save.c (http://sc2.svn.sourceforge.net/viewvc/sc2/trunk/sc2/src/uqm/save.c?revision=3551&view=markup) or load.c (http://sc2.svn.sourceforge.net/viewvc/sc2/trunk/sc2/src/uqm/load.c?revision=3551&view=markup). The description of the 'GameState' can be found in globdata.h (http://sc2.svn.sourceforge.net/viewvc/sc2/trunk/sc2/src/uqm/globdata.h?revision=3551&view=markup).
This is relatively easy code to understand.
But note that parts of the saved games are compressed (the stuff written with 'cwrite()' and variants), and that part you shouldn't try to understand. The compression/decompression routines for this are in src/libs/decomp/src/libs/decomp (http://sc2.svn.sourceforge.net/viewvc/sc2/trunk/sc2/src/libs/decomp/), for the sadistic.

Jucce: The credits are actually part of the compressed part of the saved games; your method of finding it may fail when the data around it changes. I'm actually surprised that you managed to get it like this at all.

Sadistic? Does that mean... fiddling with it will give you power? Hm... yeah, that sounds about right. Never mind. :P

I just want to clarify that I got it from reading the UQM.exe process memory and not from the save game. And in the memory it seems to be stored in a consistent way at the same (relative) location.

You're right. That should have been "masochistic".

Ah. Yes, it would be. I should have read better.