Hi there,,

 

I am interested in making mods for games including gta. I am amazed that a mod like lcpdfr can exist and actually work well (depending on how you tweak it). I want to start making mods for games but I don't know where to start. I understand that once mods are created, that people make tools so that many people can add stuff to it like skins and models. What I'm asking is how do people begin to reverse engineer a game so that you understand the inner workings of a commercial game. I have a good understanding of java and a basic understanding of other programming languages. I'm sure that I would need to have a lot more knowledge of programming to start making mods, but I just want to know where someone would start the process. I'm hoping there are people with modding experience that could help me here.

 

Thanks in advance

For reverse engineering, you need good assembler and C++ skills. When studying a new game, the first thing I do is checking its protection. If it has one, I try to get rid of it so I can access the real assembler code. This often involves simple memory dumping. Then I load the code into IDA for further analysis. Other useful tools are OllyDbg, Cheat Engine, Scylla etc.  Most modern games make use of RTTI, so parsing that is always a helpful first step. Strings (especially debug leftovers) are also a very good indicator for what the game might be doing. From now on, it largely depends on what I want to do. If I'm interested in game files, I check for APIs accessing files. If I'm interested in D3D stuff, I look for DirectX APIs etc. It's all up to you really what you want to do. You may want to check my blog, where I have some posts about early W_D analysis (http://blog.lms-dev.com/reverse-engineering/watch-dogs-first-re-impressions/ and following posts).

Wish I could understand all this stuff :(

For reverse engineering, you need good assembler and C++ skills. When studying a new game, the first thing I do is checking its protection. If it has one, I try to get rid of it so I can access the real assembler code. This often involves simple memory dumping. Then I load the code into IDA for further analysis. Other useful tools are OllyDbg, Cheat Engine, Scylla etc. Most modern games make use of RTTI, so parsing that is always a helpful first step. Strings (especially debug leftovers) are also a very good indicator for what the game might be doing. From now on, it largely depends on what I want to do. If I'm interested in game files, I check for APIs accessing files. If I'm interested in D3D stuff, I look for DirectX APIs etc. It's all up to you really what you want to do. You may want to check my blog, where I have some posts about early W_D analysis (http://blog.lms-dev.com/reverse-engineering/watch-dogs-first-re-impressions/ and following posts).

That just reminded me of one of my favorite quotes from The Dark Knight film...

Bruce Wayne - "Am I supposed to understand any of that?"

Lucious Fox - "No. I just wanted you to know how hard it was."

Thanks for all you do LMS!

Thanks for the info. It looks like I have a LOT more to learn before can start attempting to mod.

Well, you asked about studying a game and actually developing tools to make mods, so yes, that requires a lot of knowledge. But it's great fun as you can do whatever you like with the game/engine. Writing mods using existing tools not so much :P