Prismelon

A Lua-based user-friendly framework along with tools designed specifically for modding the classic game Plants vs. Zombies through memory manipulation, which is significantly easier and more versatile than manually finding and editing addresses, creating Cheat Engine scripts, or editing decompiled/remake versions of the game.

Traditionally, Plants vs. Zombies modding is tedious and error-prone:

❌ Manually editing the executable with HxD (requires backups, is slow and not advanced)
❌ ...Which leads to restarting the game for every little change
❌ Creating brittle Cheat Engine .CT scripts (difficult to create and debug)
❌ Managing multiple game executables for different mods, merging mods is often difficult
❌ Swapping asset folders manually for visual changes
❌ Advanced C++ knowledge to implement advanced features to the game through the decomp

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❓ Why it's a good alternative

Prismelon overcomes most of the issues with clever alternatives, specifically, this project is divided in a three-part architecture:

1. Lua Framework _(mods/core/)

   A carefully designed framework that abstracts away low-level memory manipulation.
   What would normally require manual ASM injection and manual address lookups becomes more straightforward:
   print(game.sun()), game.placePlant(0, 0, Plants.melon_pult.id), both syntaxes go through memory lookups and ASM injection on the second one, but it remains simple to understand even for newcomers to programming, allowing a bigger majority of people to try modding!

2. CLI for Developers _{(Prismelon-Dev.exe)}

   Prismelon, or, better, Prismelon-Dev.exe, is a standalone tool I've developed to be just as simple as the framework to use, it's utility is to easily test and debug your mods and scripts, with a simple CLI interface.
   The game is attached and scripts can be easily run, e.g. through the command run example.lua; the command lua lets you create in-lined wrapped mods that are executed right away: lua game.placePlant(4, 3, Plants.sunflower.id), which is a good way of testing if your mod is working correctly, "prints" are shown in the CLI in real time, allowing you to watch out variables... lua print(memory.readInt(0x123456)).

3. End-User Launcher _{(Prismelon.exe)} (in development)

   A visual interface for anyone to manage and launch multiple mods simultaneously without any development knowledge required. If all you want is to try out mods and scripts, this is all you need (along with the framework).

Pre-Requisites

• Your game version MUST be exactly 1.0.0.1051 (EN), as it's the most documented and known. Different versions means different memory addresses! (You can look up the version by right clicking your PlantsVsZombies.exe -> Properties -> Details -> Product Version)
• Your game should be patched for mods that modify game assets to work. A ready copy of the game can be found in the modding docs.

Structure

mods is necessary, must be in the same path your game is. The mods/core folder contains the framework:

• mem.dll is a C++ library which contains all what's needed for attaching to the process and allow memory manipulation
• memory.lua is a wrapper of mem.dll, contains well-documented functions and more features
• definitions.lua, offsets.lua... are huge files containing hexadecimal addresses of pretty much anything that can be modified in the game
• utils.lua is a simple utilities file that implements common features such as math.clamp(), table.copy(), table.substract, ...

Tipologies of Mods

A mod can either be "simple/quick" and work by itself inside mods/quickmods, or, more commonly, be a separate folder inside mods, inside will be a lua script named after the folder (e.g: mods/example/example.lua) or universally main.lua. A mod/quickmod can run Synchronously, Asynchronously or in Background:

• Synchronously means it will be executed inside prismelon-dev.exe itself, you won't be able to run commands until the script has ended (usually instantaneous)
• Asynchronously means it will be executed in another window through a batch file, you will be able to run commands in the main CLI
• In Background means it will be executed asynchronously and hidden; if an error occurs, a window will pop up

Getting Started

(to create a mod):

1. Create a folder inside "mods"
2. Create a .lua file inside the folder, make sure its name is the same as the mod (e.g: mods/test/test.lua) or main.lua
3. Write the script (look up the examples) and execute it through Prismelon-Dev.exe via "run", (e.g: run test)

(to create a quickmod, a mod that doesn't modify game assets) 2. Create a .lua file inside mods/quickmods/ 3. Write the script (look up the examples) and execute it through Prismelon-Dev.exe via "run", (e.g: run test.lua), note the ".lua"

Documentation

_{This idea was inspired by the project "PvZ Toolkit" A big thank you to the developers! Along with whoever made the game fandom, which helped alot with understanding how this game is traditionally modded, and how I could make it easier and possible for everyone!}