/vr/ - Retro Games

>>2469079
>>2486847
5) Adding code as complicated as a enemy requires insight into the part of the engine that controls entity behavior, and now you're getting into complicated stuff. All I'm going to say is you can insert code like I told you, but if you can do the hack, that won't be news to you.

6) SM map. Read up on SNES video registers (romhacking.net snes dev docs). Map out the NMI code (The 16-bit NMI vector at $00:FFEA points to it in bank $00). Find where video registers get updated (trace NMI, cross reference with snes dev docs). Find the associated RAM that stores the video register settings (from trace). Examining the video register settings, trace and determine which data updates the automap on BG3. Next set breakpoints for writes to the RAM address that forms the buffer for data to be sent to VRAM during the NMI. Disassembling the code that writes this data will give you a way to understand where it is stored and how it is interpreted. Even if you don't disassemble this code, you can find out where it reads data from (ie the in game representation of the automap), and you can use corruption techniques from there.

Caveat about PSX: It may be that data on disc is compressed/encrypted, which greatly complicates editing a ROM image. If so, you'd have to write an uncompress/compress routine just to even get started. Not trivial stuff for an amateur. Also PSX has a disc system, whereas SNES has full access to the entire ROM all at once. SNES is conceptually easier to understand.

>>2433461