DNCity

NeoForge (Minecraft 1.21.1) mod written in Kotlin. Voice chat (close-range Opus + PTT radio on codec2), TACZ weapon sounds through a bundled FMOD Studio bank, server-pushed /music playback, and an experimental native window/JCEF browser overlay. See AGENTS.md for the full architecture writeup — this file only covers getting a dev environment running.

Requirements

• JDK 21 (exactly this major version — see AGENTS.md's "Toolchain" section for why the repo used to require JDK 25 and no longer does). Point JAVA_HOME at a JDK 21 install, or let the Gradle toolchain resolver (org.gradle.toolchains.foojay-resolver-convention) download one.
• Git LFS — *.bank files (FMOD Studio banks) are tracked via LFS (.gitattributes). Install it and run git lfs install once per machine before cloning/pulling, or the bank files will be checked out as tiny pointer text files instead of real audio data.
• A C/C++ toolchain, only if you intend to rebuild the native modules under engine/ (most day-to-day Kotlin/Java work on the mod itself does not touch these — the built .dlls are checked into each module's generated resources dir until you actually change native code):
  • engine/audio (miniaudio + codec2) needs clang targeting x86_64-w64-mingw32 (MinGW-w64) — codec2's C99 _Complex code doesn't build against the MSVC ABI. Needs cmake and a MinGW-w64 sysroot on PATH.
  • engine/fmod and engine/window build with plain MSVC (Visual Studio Build Tools) via cmake — no special toolchain needed.
  • See each module's AGENTS.md section / CMakeLists.txt comments for exact flags if a build fails.
• Windows is the only platform the native modules currently support (engine/window is Win32-only; engine/fmod/engine/audio are Windows-focused too). Linux/macOS are not set up.

Cloning

This repo uses several git submodules (vendored mod forks + codec2) wired in as Gradle composite builds (settings.gradle.kts). Clone with submodules, or init them after the fact:

git clone --recurse-submodules <repo-url>
# or, if already cloned:
git submodule update --init --recursive

Submodules in use (see .gitmodules): mods/TACZ-1.21.1, mods/First-Aid-New, mods/Automobility, mods/SuperbWarfare, mods/ModernUI-MC, mods/sodium, mods/Iris, engine/audio/vendor/codec2.

Building & running

Use the Gradle wrapper — ./gradlew (bash) or gradlew.bat (cmd/PowerShell; PowerShell can also call ./gradlew). First invocation will pull in NeoForge's toolchain and every submodule's own dependency graph, so expect a slow first sync.

• ./gradlew build — compile and build the mod jar.
• ./gradlew runClient — launch a dev client (game directory run/).
• ./gradlew runClient2 — a second dev client with a distinct username/UUID and its own game directory (run-client2/), for testing multiplayer-only features (radio, proximity voice) by connecting two clients to the same world/LAN game at once.
• ./gradlew runServer — launch a dev dedicated server (--nogui).
• ./gradlew runGameTestServer — runs all registered gametests (namespace dncity) then exits.
• ./gradlew runData — data generation, outputs to src/generated/resources/.

There's no separate lint/test task beyond runGameTestServer — this is a Minecraft mod, so most verification is done by actually running a dev client.

Each native module under engine/ (audio, fmod, window) is also a standalone Gradle project and can be built on its own: ./gradlew -p engine/<audio|fmod|window> build (they reuse the root project's Gradle wrapper distribution — no separate gradlew in those directories).

IDE setup (IntelliJ IDEA)

1. Open the repo root as a Gradle project (build.gradle.kts) — don't open a submodule directory directly.
2. Let the initial Gradle sync finish; it resolves every includeBuild(...) composite build declared in settings.gradle.kts (TACZ, First Aid, Automobility, SuperbWarfare, ModernUI-MC, Sodium, Iris, and the three engine/* native modules).
3. generateModMetadata runs automatically on sync and expands ${...} placeholders in src/main/templates/META-INF/neoforge.mods.toml (from gradle.properties) into build/generated/sources/modMetadata — edit the template/properties, not the generated copy.
4. If IntelliJ shows stale "unresolved reference" errors after adding/changing a composite build module (most often after pulling changes that touch settings.gradle.kts or add a new engine/* module), a plain incremental sync sometimes isn't enough:
   • First try the Gradle tool window's "Reload All Gradle Projects" button.
   • If that doesn't clear it, File → Invalidate Caches / Restart → Invalidate and Restart.
   • If Gradle itself throws something like Unable to find method 'DefaultGroovyMethods.collect(...)', that's a corrupted/stale Gradle daemon, not a real build error — run ./gradlew --stop to kill it, then re-sync (a fresh daemon starts automatically on the next Gradle invocation).

Configuration cache

org.gradle.configuration-cache=false is set repo-wide in gradle.properties and must stay off: mods/ModernUI-MC's Architectury Loom build silently fails to apply its access transformer under the configuration cache (confirmed by hand — see gradle.properties's comment), and configuration cache is an invocation-wide setting shared by every included build, so it can't be scoped to just that one submodule.

Editing mod metadata

mod_authors, mod_description, and the Minecraft/NeoForge version ranges live in gradle.properties, not in src/main/templates/META-INF/neoforge.mods.toml directly — the template only has ${...} placeholders the generateModMetadata task expands.