Anvil

A Godot 4 (C#) editor plugin that generates strongly-typed, compile-time-safe StringName constants for your files — no more typo-prone magic strings for asset paths, sound names, or resource keys.

Point it at a folder, and Anvil generates a nested static class full of constants, one per file, named after the file itself.

Instead of this:

GD.Print("main_theme"); // typo-prone, no autocomplete, breaks silently

You get this:

GD.Print(Audio.Music.MainTheme); // compile-time checked, autocompletes

Two modes, two different jobs

Anvil can generate constants in one of two shapes, controlled by ForgeMode. Picking the right one for each folder matters — they solve different problems:

If you're not sure which you need: if you're about to call GD.Load, you want FullPath. If you're about to compare, store, or display a name, you want Id.

Installation

1. Copy the addons/Anvil folder into your project's addons/ directory.
2. In Godot, go to Project → Project Settings → Plugins and enable Anvil.

Usage

1. Mark a partial class with [Forge]

using Anvil;

public partial class Audio
{
    // Id mode (default) — short names, for ID-based lookups
    [Forge("res://audio/music")]
    public static partial class Music
    {
    }

    // FullPath mode — full res:// paths, ready to GD.Load directly
    [Forge("res://audio/sfx", mode: ForgeMode.FullPath)]
    public static partial class Sfx
    {
    }
}

• The outer class (Audio) must be partial.
• The inner class (Music, Sfx) must be static partial and carry the [Forge] attribute.
• The path passed to [Forge] is a res:// folder — every valid file inside it becomes a constant.
• mode (optional, default ForgeMode.Id) — see the table above. Can be passed positionally ([Forge("res://audio/sfx", ForgeMode.FullPath)]) or named (mode: ForgeMode.FullPath).
• recursive (optional, default false) — when true, subfolders are scanned too and all files are flattened into the same class. If two files in different subfolders share a name, the first one found wins and the rest are skipped with a console warning naming the conflicting file. Works with either mode, in any argument order: [Forge("res://audio/sfx", recursive: true, mode: ForgeMode.FullPath)].

2. Generate

In the Godot editor, go to Project → Tools → Generate Anvil IDs.

Anvil scans your project for every [Forge] attribute, and for each one writes a generated file at:

res://addons/Anvil/Generated/<OuterClassName>.anvilgen.cs

Re-running generation clears out old generated files first, so it's always safe to run again after adding or removing assets.

3. Using Id mode

public partial class Audio
{
    public static partial class Music
    {
        public static readonly StringName MainTheme = "main_theme";
        public static readonly StringName BossFight = "boss_fight";

        public const string EnumNames = "main_theme,boss_fight";
    }
}

These constants hold a name, not a path — use them wherever your code compares, stores, or looks something up by that name:

if (currentTrackName == Audio.Music.MainTheme) { /* ... */ }
saveData.LastPlayedTrack = Audio.Music.BossFight;

Id mode also generates an EnumNames const: a comma-joined string of every file name in that folder, ready to drop straight into PropertyHint.Enum:

[Export(PropertyHint.Enum, Audio.Music.EnumNames)]
public string SelectedTrack;

This gives you an inspector dropdown of every file in the folder, kept in sync automatically every time you regenerate. A file name containing a comma is excluded from EnumNames (it would corrupt the hint string) but still gets its own constant; a warning is printed naming the file.

4. Using FullPath mode

public partial class Audio
{
    public static partial class Sfx
    {
        public static readonly StringName Digging = "res://audio/sfx/digging.ogg";
        public static readonly StringName Planted = "res://audio/sfx/planted.ogg";
    }
}

These constants hold a complete, loadable path — pass them straight into GD.Load, no string-building required:

audioPlayer.Stream = GD.Load<AudioStream>(Audio.Sfx.Digging);

There's no EnumNames in this mode — a full path isn't a meaningful value for an inspector dropdown, so it's skipped.

Configuring valid file extensions

By default, Anvil picks up these extensions:

.wav .ogg .mp3 .tscn .tres .glb .blend .fbx

You can change this list in Project Settings under:

anvil/generator/valid_extensions

Any file in a [Forge]-marked folder whose extension isn't in this list is ignored. .import files are always ignored.

Notes

• Generated files live under res://addons/Anvil/Generated/ and are marked with a .gdignore, so Godot won't try to import them as resources.
• Generated files are overwritten on every run — don't hand-edit them.
• File names are converted to PascalCase for the generated constant name (e.g. main-theme.ogg → MainTheme).
• With recursive: true, all matched files across every subfolder are flattened into one class. Duplicate names across subfolders are not both included — the first match wins, and later duplicates are skipped with a console warning.
• mode only changes what a constant holds (a name vs. a full path) — it doesn't change how files are discovered, so recursive, extension filtering, and duplicate handling all work the same way regardless of mode.

License

MIT