Quick Look plugin for previewing .3mf, .stl, and .gcode 3D printing files on macOS.
Press Space in Finder to see interactive 3D previews — no need to open a slicer.
- Instant preview — shows the embedded thumbnail immediately for
.3mffiles, with a "Show 3D" button to load the full interactive view on demand - G-code toolpath preview with layer scrubber, animation playback, and 4 color modes (layer rainbow / travel-vs-extrusion / feedrate heatmap / uniform)
- Interactive 3D preview with mouse rotation, pan, and zoom
- Progress bar while loading large models (2M+ triangles)
- Supports
.3mf(Bambu Lab, PrusaSlicer, etc.),.stl(binary and ASCII), and.gcode - Fast byte-level 3MF parser — 5–10x faster than XML-based parsing for large files
- Signed and notarized for easy distribution
brew install --cask guanchzhou/tap/threemf
- Download
threemf.zipfrom Releases - Unzip and move
threemf.appto/Applications/ - Open the app once to register the Quick Look extensions
threemf ships an optional headless CLI for thumbnail generation and file inspection — useful for CI pipelines, automation, or print-farm dashboards.
xcodegen generate
xcodebuild -scheme threemf-cli -configuration Release build
swift build -c release
.build/release/threemf-cli info path/to/file.3mf
threemf-cli info <file> # prints JSON: format, counts, bounding box, materials
threemf-cli thumbnail <input> <output.png> [--size N] # renders 3D thumbnail (default 512×512)
macOS 14 (Sonoma) or later. Apple Silicon by default; release builds ship a universal binary (arm64 + x86_64).
Requires XcodeGen:
brew install xcodegen
xcodegen generate
xcodebuild -scheme ThreeMFQuickLook -configuration Release build
To build a universal (arm64 + x86_64) binary locally:
xcodebuild -scheme ThreeMFQuickLook -configuration Release \
ARCHS="arm64 x86_64" ONLY_ACTIVE_ARCH=NO build
MIT