A level editor for Super Mario Galaxy 1 & 2.
Note
Supernova is in early alpha. Crashes and bugs are likely, and there is a real risk of losing level progress. Relying on the editor for serious work is not recommended yet. Keep backups of anything you care about.
Supernova is a level editor for Super Mario Galaxy 1 and Super Mario Galaxy 2, built for editing objects, cameras, paths, and stage data, with an eye toward eventually previewing levels using reimplemented game and camera behavior.
- Written in C#, using Dear ImGui for the interface and OpenGL for rendering.
- In development since February 2026.
- Built from the ground up. A custom engine for simulating object movement and animation, with rendering written from scratch.
- Inspired by the Super Mario Galaxy 1 decompilation. More decompiled game code means more opportunities to simulate the game's own behavior faithfully.
- Format-accurate. Yaz0, RARC, and BCSV files are written back 1:1 with the originals.
The screenshots and clips below show content that is subject to change; the editor is always evolving.
Click to select an object, then move or rotate it on a specific axis with a custom on-screen gizmo.
Actors play their real waiting animations (and other applicable animations) right in the editor. Object movement along rails and rotation simulates live in the viewport.
Every object type gets its own editor for its parameters, not just raw fields. Booleans
become checkboxes, list values become dropdowns, and Obj_arg descriptions show up as
tooltips so developers can identify what each argument does. The data comes from the Luma's
Workshop Object Database, and the same treatment applies to path_arg and point_arg.
Rotating and moving map parts simulate live in the viewport as you tune their parameters.
Supports RailMoveObj and RotateMoveObj, with more planned before release.
Edit stage cameras and visualize specific camera types...including CAM_TYPE_XZ_PARA, right in
the editor. Place a dummy player to see how the camera would react. Many more camera types are
planned.
Edit a galaxy's intro camera keyframe by keyframe and preview the result live in the viewport.
Edit a galaxy's scenarios: power stars, comets, and per-zone layers without leaving the editor. It also supports adding new stars and layers.
Timeline editing for demo cutscenes.
Make your own edits while never touching the retail filesystem. Each project keeps its own output directory and icon, so retail files stay untouched.
Render and edit LightData, and apply it to the level (including an "auto" mode).
Edit a galaxy's stage BGM.
Edit ProductMapObjDataTable with a helper that lists known objects.
Standalone editor windows loaded from a plugins/ folder for hack extensions that add their
own BCSVs or add fields. Approve them under Settings on the galaxy list; open them from Tools > Plugins.
See docs/PLUGINS.md.
Every button, label, and tooltip goes through a lookup keyed by its English text, so the editor
can be translated by dropping a <code>.json into the lang/ folder. Pick a language under
Settings; untranslated strings fall back to English. See lang/README.md. If you want to contribute a language, ask in the Luma's Workshop Discord!
- User-created themes
Obj_argvisualizers (e.g. range values)- More per-object rendering
- More camera types and Map Parts behaviors
Requires the .NET 8 SDK. The editor currently targets
net8.0-windows.
git clone https://github.com/SMGCommunity/Supernova.git
cd Supernova
dotnet build SMGEditor.sln -c Release
dotnet run --project src/SMGEditor.EditorYou will need your own legally obtained Super Mario Galaxy 1 / 2 files. Point the editor at an extracted game dump and it will automatically determine the game.
Questions, help, and discussion happen in the Luma's Workshop Discord.
- The Luma's Workshop Object Database
- The Super Mario Galaxy decompilation project (Petari)