QuickLookStep.app

Fast QuickLook & Finder thumbnail support for STEP (.step / .stp) 3d model files on macOS.

Built with Swift + SwiftUI, SceneKit, and Formlabs/foxtrot.

✨ What does it do?

This allows you to quickly preview STEP files from Finder before opening them in your CAD tool. It will not render your STEP files as well as your CAD tool, but it will almost certainly open them faster!

QuickLookStep.mov

🚧 Requirements

• macOS 14.6 (Sonoma) or newer
• M1 or above CPU (Apple Silicon)

💻 Installing

You can either download QuickLookStep.app from the Releases page or via Homebrew:

brew tap johnboiles/homebrew-tap
brew install quicklookstep

After installing, open QuickLookStep.app once to enable the extensions.

If for some reason the extensions aren't enabled automatically:

• Open System Settings > General > Login Items and Extensions
• Click the (i) next to QuickLookStep
• Turn the switch on for both options under QuickLookStep
• Cick Done

🕶️ Usage

Open a Finder window and select a .step or .stp file. You should be able to preview it from Finder with Quick Look (using spacebar) or see the thumbnail in the sidebar in column view. QuickLookStep.app does not need to be open for the extensions to work.

🐞 Known issues

• Some STEP files don't load. The underlying Foxtrot library doesn't like them.
• Some STEP files have holes. Probably this is also a Foxtrot thing, but I could also be making a mistake in how I'm loading geometry to SceneKit. More testing against Foxtrot is needed. For this app, it's always better to be fast than perfect, but ideally it can be both 😀
• The examples in the Foxtrot README.md suggests Foxtrot supports textures. I don't have that hooked up in SceneKit yet.
• Very large assemblies can take a long time to load and the extensions get stuck for a bit. Better timeouts could probably protect against this.

🔫 Troubleshooting

If you used older versions of QuickLookStep.app (especially <v1.5), make sure to delete them and to empty trash (Finder -> Empty Trash...). I've noticed macOS will sometimes try to use old extensions from the Trash! Then you should restart Finder:

killall Finder

If restarting Finder doesn't make it work, I run this to do everything I know to do to clear the macOS cache:

pluginkit -r -u com.johnboiles.QuickLookStep.StepThumbnail
pluginkit -r -u com.johnboiles.QuickLookStep.StepPreview
pluginkit -a /Applications/QuickLookStep.app
qlmanage -r
qlmanage -r cache
pluginkit -e use -i com.johnboiles.QuickLookStep.StepThumbnail
pluginkit -e use -i com.johnboiles.QuickLookStep.StepPreview
killall QuickLookUIService
killall Finder

And of course rebooting is also worth trying!

🤝 Contributing

Let's make this better together. Issues and PRs are welcome.

This project is licensed under the terms of the MIT License. Do what you want with it but I don't guarantee it works. If you do something neat with it, I'd always appreciate a shoutout!