HotReload for MelonLoader

HotReload for MelonLoader

A tool for mod authors: rebuild your mod and the running game picks up the new build, without a restart. HotReload is a MelonLoader plugin for any Unity game, Mono or IL2CPP. It cleans up after the old build, so the new one starts as if the game had just launched.

Features

• []Reload on build: copy a new build into Mods while the game runs, and HotReload reloads it a moment later. Mod DLLs are never locked, so your build's copy step just works. Or press F8.[/]

  []Cleans up the old build: Harmony patches (from any Harmony instance), MelonLoader callbacks and event handlers, preference categories, coroutines, timers and other callbacks the game still holds, objects kept across scenes, injected Il2Cpp classes, AssetBundles, and hooks made outside Harmony that the mod keeps in a field.[/]

  []Starts the new build properly: replays the scene callbacks for the scenes already open, calls the start callbacks that already fired, and can hand state over from the old build to the new one.[/]

  []Reloads what belongs together: mods that reference the changed one, and the helper libraries they use. Plugins and UserLibs libraries reload too. UnityExplorer with UniverseLib reloads fully.[/]

  []Tells you what happened: one log line per reload, and a clear message when a new build fails to load.[/]

  Requirements

  • []MelonLoader 0. 6. 0 or newer; 0. 7. 1 or newer recommended (keeps mod DLLs unlocked while the game runs).[/]

    []An IL2CPP game, or a Mono game on Unity 2018. 1 or newer. One DLL for both.[/]

    Installation

    • []Install MelonLoader into the game folder and start the game once.[/]

      []Extract the zip into the game folder, so that HotReload.dll ends up in the Plugins folder (not Mods).[/]

      Steam Deck / Linux (Proton): the same, with MelonLoader's launch option

      WINEDLLOVERRIDES="version=n,b" %command%Bind a back grip to F8 in the game's Steam Input layout to use the reload key.

      Quick start

      • []Start the game. The MelonLoader log shows what HotReload could enable.[/]

        []Build your mod and copy the DLL (and its .pdb) into Mods, as your build probably already does.[/]

        []The mod reloads. F8 reloads every DLL that changed, if automatic reloading is off or a change was missed.[/]

      Plugins and UserLibs libraries are locked while the game runs: add your project's build folder to ExtraWatchPaths in the settings, and HotReload reloads them straight from there.

      Making your mod reload cleanly

      Most mods reload as they are. For the rest, the GitHub page has a guide for mod authors: undo what you changed outside Harmony, set things up for what already exists after a reload, unregister your objects from game lists before destroying them, keep scene callbacks cheap, and a few more rules, with code and a checklist. The included HotReloadCheck tool scans compiled mods and lists what they would need.

      Settings

      UserData/HotReload.toml, created on the first start; edits apply while the game runs. Automatic reload on or off, the reload key (chords such as LeftControl+F8 work), extra folders to watch, and assemblies to ignore.

      Compatibility

      • []MelonLoader 0. 6. 0 to 0. 7. 3, checked against each release on every build.[/]

        []Tested in No Rest for the Wicked (IL2CPP) on Windows and on a Steam Deck, and in PEAK (Mono).[/]

        []A developer tool: it changes nothing in the game itself, and does nothing until a mod DLL changes or you press the reload key.[/]

        Source

        Source code, the guide for mod authors, documentation and issue tracker: https://github.com/Vergir/MelonLoader-HotReload

        License: MIT