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Persona 3 Dual

Game Dev Setup

Note: This setup only works for persona-3-dual and aegis-engine. p3d-amicitia dev setup is NOT covered.

The team uses melonDS for testing, VS Code as the development IDE, & Docker as the development environment.

Prerequisites

Section titled “Prerequisites”

You need to have melonDS, VS Code, & Docker already installed on your system.

melonDS

Section titled “melonDS”
  • Go to Config → Emu settings → Devtools
  • Ensure Enable GDB stub is checked
  • Ensure the ARM9 port is 2345 & Break on startup is checkedWhen debugging, ensure that melonDS is already launched

VS Code

Section titled “VS Code”
  • Ensure that the Dev Containers extension is installed

Docker

Section titled “Docker”
  • Ensure that Docker is launched & runningDocker needs to be running whenever you want to code

1. Clone the Repo

Section titled “1. Clone the Repo”

persona-3-dual

Section titled “persona-3-dual”
git clone --recurse-submodules https://github.com/p3d-project/persona-3-dual.git
cd persona-3-dual

aegis-engine

Section titled “aegis-engine”
git clone --recurse-submodules https://github.com/p3d-project/aegis-engine.git
cd aegis-engine

2. Set Up Code Formatting

Section titled “2. Set Up Code Formatting”

This project uses pre-commit to auto-format all source files before every commit. It handles C/C++ (clang-format), Python (black + ruff), and web files (prettier).

Install pre-commit:

# macOS

brew install pre-commit# Windows / Linuxpip install pre-commit

Register the hooks:

pre-commit install

That's it. Hooks run automatically every time you run git commit.

What happens during a commit:

The hooks reformat your staged files in-place. If any file is changed, the commit is aborted so you can review the diff. Just re-stage and commit again.

Run hooks manually (e.g. before opening a PR):

pre-commit run --all-files

Windows note: prettier requires Node.js. pre-commit downloads a local copy automatically the first time you run pre-commit install or pre-commit run.

3. Open the repo in VS Code

Section titled “3. Open the repo in VS Code”

Open the persona-3-dual repo in VS Code. Then, click the bottom left >< icon & select Reopen in Container

You may also see a notification on the bottom right to Reopen in Container. This method also works! If this is your first time launching the container, it may take a few minutes for Docker to install the image. Otherwise, VS Code should re-launch within a few seconds.

You are now ready to code!

Building

Section titled “Building”

To build, simply use make. If you do not need to update the SD card image, use make SKIPSD=1

If this error appears

[in#0 @ 000001fea6e491c0] Format mov,mp4,m4a,3gp,3g2,mj2 detected only with low score of 1, misdetection possible!

[in#0 @ 000001fea6e491c0] moov atom not found

[in#0 @ 000001fea6e48f80] Error opening input: Invalid data found when processing input

Error opening input file C:/p3d/persona-3-dual/assets/video/base.mp4.

Error opening input files: Invalid data found when processing input

Its most likely due to non pulled LFS media. Pull it with

git lfs pull

Debugging

Section titled “Debugging”

Ensure melonDS is already launched & awaiting the debugger

  • Build in debug mode (you can use the make debug task or just open a terminal inside the container and run make DEBUG=1)
  • In VS Code, go to the Run and Debug tab on the left panel, and select [Docker] (gdb) Connect to melonDS

You are now ready to debug!

If you are unable to connect the debugger to melonDS, ensure that melonDS is launched WITH THE GAME & has the below settings configured

debug