Files in the folder
What the files and folders inside the MeshOptimiser folder are for, which ones you use, and which ones to leave alone.
You only ever need to double-click one file: the launcher for your system. The rest is the app itself, and almost all of it is inside the folder app, so the top of the folder stays short.
At the top of the folder
start.bat- The launcher for Windows. Double-click it to start the app.
start.command- The launcher for macOS.
start_hidden.vbs- Windows: starts the app like
start.bat, without showing the launcher window. start.ico- The icon for a shortcut. See Add a shortcut or an icon.
Install MeshOptimiser.bat- The installer for Windows. See Install on Windows.
README.txt,README.md,LICENSE- A short quick start in plain text, the project’s description, and the licence.
app- Everything else: the program and what it creates. The launchers at the top start the ones inside it.
Inside app: the ones you can use
step2glb.bat,step2glb.command- Convert a STEP file that you drag onto them, without opening the viewer.
Folders the app creates (inside app)
.venv- The app’s own Python environment, created on the first run. It can take up to about 2 GB. It is safe to delete: the launcher builds it again, which takes a few minutes. On macOS the folder is hidden in Finder, because its name starts with a dot.
inbox- Where STEP files are converted. The finished GLB files stay here for a day. Inside it, the folder
cachekeeps converted models, so opening the same STEP file with the same settings again is quick. It never holds more than 3 GB. exports- Where the files that Claude’s tools make for you are saved: exports, saved scenes, pictures and videos.
The app itself (inside app)
serve.py- The small local server. It hands the app’s pages to your browser and starts the converter when you drop a STEP file.
step2glb.py- The converter from STEP to GLB.
gridmesh.py- A part of the converter: the even strips on curved faces.
index.html- The viewer’s page.
js- The viewer’s scripts.
app.jsis the program; the others are parts of it, such asholefill.js(the hole filler behind Remove holes),mesh-worker.js(a background worker so the window stays usable while Remove holes and Decimate run) andcloner.js(linear, grid and radial arrays of a part). vendor- The libraries the viewer needs, bundled so that it starts without the internet.
assets- The app’s icons, pictures and help clips.
knowledge- The help articles and playbooks that Claude reads when it connects.
manifest.webmanifest- What lets Chrome and Edge install the page as an app.
requirements.txt- The list of Python add-ons the launcher installs: cadquery-ocp, trimesh and numpy.
version.json,updater.py- The version you have, and the program that applies updates.
ui.ps1- Draws the launcher window on Windows.
The download does not hold the project’s tests, tools, docs or changelog. They are in the repository, and the changelog is on this site.