Save Scene and Save Scene As: save a project as .mru or glTF

A scene is everything in the Scene tree: the objects, their groups and their positions. Save it as a MeshInspector scene (.mru) to continue your work later exactly where you stopped. To give an object to other software, export it instead (see Exporting Objects).

Where the save commands are

The save commands are on the Home tab. Save Scene and Export are also at the top left of the window.

Command	Shortcut	What it does
Save Scene	Ctrl+S (Cmd+S on macOS)	Saves the scene to its .mru file.
Save Scene As	Ctrl+Shift+S (Cmd+Shift+S)	Saves the scene to a new file: .mru, .gltf or .glb.
Save Selected	—	Saves only the selected objects, with the groups they are in, as a scene.
Export	—	Saves the selected objects to separate files, for example STL.

The window title shows the name of the scene file and a * when the scene has unsaved changes.

Save vs Export

	Save Scene (.mru)	Export
What is saved	All objects of the scene in one file	The selected objects, one file each
Object types	All, including G-code, measurements and primitives	Meshes, point clouds, polylines, volumes and distance maps
Scene tree	Kept, with groups and names	Not kept: only the file names
Position of objects	Kept as the transform of each object	Applied to the coordinates of meshes, point clouds and polylines; not applied to volumes and distance maps
Colors and textures	Kept	Kept by some formats (see Exporting Objects)
Display and selection	Kept: visibility, display settings, selected triangles	Not saved
Units	Model Units are stored	Stored only by 3MF
Who opens the file	MeshInspector	Other software: slicers, CAD, CT viewers

For 3D printing, export the mesh as STL or 3MF: a printer or slicer cannot read a .mru file. Keep the .mru file as your working copy.

Save Scene (Ctrl+S)

Save Scene (Ctrl+S, Cmd+S on macOS) writes the scene to the file it belongs to:

• A scene that you opened from a .mru file is saved back to this file.
• If you opened another file into an empty scene, for example part.stl, Save Scene writes part.mru into the same folder. If such a file already exists, the new file gets a number, for example part (1).mru.
• A new scene that has no file yet opens the Save Scene As dialog.

An empty scene cannot be saved: the button is greyed out, and its tooltip says "Scene is empty - nothing to save".

Save Scene As

1. Click Home › Save Scene As or press Ctrl+Shift+S (Cmd+Shift+S on macOS).
2. Choose the folder, enter the file name and choose the format:
   • .mru, the MeshInspector scene, keeps everything (see What a .mru file keeps).
   • .gltf or .glb keeps the meshes with their tree, positions, colors and textures, for other 3D software. Point clouds, polylines, volumes and G-code are not written to glTF. A .glb file is one binary file.
3. Click Save.

After you save as .mru, Save Scene saves to this new file. After you save as .gltf or .glb, Save Scene writes a .mru file with the same name next to it. Use Save Scene As to keep versions of your work, for example before a large edit.

Save Selected

Home › Save Selected saves only part of the scene: the branches of the Scene tree that hold the selected objects.

1. In the Scene tree, select the objects to save.
2. Click Home › Save Selected.
3. Enter the file name, choose the format and click Save.

What the file gets:

• The selected objects and the groups they are in, so the tree keeps its structure. Objects that you did not select are left out, even when they are in the same group.
• With .mru, .gltf or .glb, the result is a scene file, as with Save Scene As.
• With .obj, all selected meshes are written into one OBJ file, each in its place in the scene. This format is offered only when all selected objects are meshes.

Save Selected does not change the file of the current scene: the next Save Scene still saves the whole scene to its own file. Use it to send part of a scene to a colleague or to split a large scene into smaller ones.

What a .mru file keeps

A .mru file stores:

• the Scene tree with its groups and object names;
• the geometry of every object: meshes, point clouds, polylines, volumes, distance maps, G-code, measurements and primitives;
• the position of every object, and whether it is visible, selected or locked;
• the selected triangles and edges;
• vertex and triangle colors, textures and texture coordinates;
• the display settings of every object, such as faces, edges, points and shading;
• the Model Units of Settings › Units.

Settings › Application › MRU Inner Formats sets how the geometry is stored inside a .mru file:

Setting	Options	Default
Mesh Format	CTM (smallest file, slowest), PLY (fast and still small), MRMESH (largest, fastest, without losses)	PLY
Points Format	CTM, PLY	PLY
Voxels Format	VDB (efficient for sparse data), RAW (simplest, largest)	VDB

Unsaved changes

MeshInspector asks before it removes unsaved work:

• Home › New opens the New Scene window (see Start a new scene).
• Closing the app opens the Application Close window.

Both ask Save your changes?: Save saves the scene first, Don't Save goes on without saving, and Cancel returns to the scene.

In the web app, Save Scene and Save Selected are not available: export the objects you need.

Good habits

• Save early and often with Ctrl+S (Cmd+S).
• Before a large edit, save a copy with Save Scene As.
• Keep the .mru file as your working copy and export STL or 3MF only for the printer or another program.
• Home › New clears the undo history, so save the scene before you start a new one.