Data Layout & JSON Structure

This document outlines the standard project structure for data-driven features using JSON.

1. Directory Structure

Data files are NO LONGER centralized. They live within their owning plugin.

Standard Path: Plugins/<Category>/<PluginName>/Data/

Examples:

• Objects: Plugins/Resources/ProjectObject/Data/Objects/Sword.json
• Boot: Plugins/Boot/Orchestrator/Data/dev_manifest.json

Note: We prioritize plugin modularity. Data/ (plugin root) contains the Source of Truth (JSON/Schemas). Files are generated/staged from here into Content/ or packaged builds.

2. Relative Paths in JSON

When referencing other assets or files within JSON, use standard UE soft paths or relative paths resolved by helper functions.

Asset References

Use the standard /Game/... or /PluginName/... soft object path.

{
  "icon": "/ProjectObject/Textures/Icons/Sword_Icon.Sword_Icon",
  "staticMesh": "/ProjectWorld/Meshes/Weapons/SM_Sword.SM_Sword"
}

JSON-to-JSON References

When a JSON file (like a layout) references another JSON file (like a child fragment), the path is relative to the plugin's Content/Data folder.

Example: ui_definitions.json:

{
  "id": "HUD_Main",
  "layout_json": "Layouts/HUD_Layout.json" 
}

Resolves to: Plugins/.../Content/Data/Layouts/HUD_Layout.json

3. C++ Path Resolution

Do NOT hardcode paths. Use FProjectPaths from ProjectCore.

#include "ProjectPaths.h"

// Get the base Data directory for a plugin
FString DataDir = FProjectPaths::GetPluginDataDir(TEXT("ProjectUI"));
// Result: ".../Plugins/UI/ProjectUI/Content/Data"

// Check for a file
bool bExists = FProjectPaths::PluginDataFileExists(TEXT("ProjectUI"), TEXT("config.json"));

4. Packaging

All files in Content/Data are automatically staged into the PAK/IoStore in cooked builds (Game, Client, Server) via Build.cs RuntimeDependencies.

• Editor: Reads directly from source Content/Data.
• Shipped: Reads from staged Content/Data (UFS).