A macOS Quick Look extension for .3mf files (3D Manufacturing Format). Press Space on any .3mf file in Finder to see a 3D preview of the model — no slicer needed.
- Quick Look integration — press Space in Finder to preview
.3mffiles - 3D rendering with SceneKit — proper lighting, shading, and materials
- Auto-rotating model — spins around the vertical axis so you can see all sides
- Interactive controls — orbit and zoom with your mouse/trackpad in the preview
- Multi-object support — handles files with multiple mesh objects (Bambu Studio, PrusaSlicer, etc.)
- Drag-and-drop — drop
.3mffiles into the host app for inline preview
- Download the latest release (or build from source)
- Move
Preview3MF.appto/Applications - Launch it once — this registers the Quick Look extension
- Go to System Settings → Privacy & Security → Extensions → Quick Look and make sure PreviewExtension is enabled
- That's it — press Space on any
.3mffile in Finder
Tip: If Quick Look doesn't pick it up immediately, run
qlmanage -rin Terminal to reset the Quick Look cache.
Requires Xcode 15+ and macOS 13+.
git clone https://github.com/cavoco/Preview3MF.git
cd Preview3MF
xcodebuild -scheme Preview3MF -configuration Release buildOr open Preview3MF.xcodeproj in Xcode and hit Cmd+R.
.3mf files are ZIP archives containing XML model data. The extension:
- Extracts all
.modelfiles from the archive (using ZIPFoundation) - Parses
<vertex>and<triangle>elements from the XML - Builds SceneKit geometry with per-face normals for flat shading
- Renders with a 3-point lighting setup and auto-framed camera
├── Preview3MF/ # Host app (SwiftUI)
│ ├── Preview3MFApp.swift
│ └── ContentView.swift # Drag-and-drop preview UI
├── PreviewExtension/ # Quick Look extension
│ ├── PreviewViewController.swift
│ └── Info.plist # UTI + QL config
└── Shared/ # Used by both targets
├── ThreeMFParser.swift # ZIP extraction + XML parsing
└── SceneBuilder.swift # Mesh → SCNScene with lighting
MIT