Katydid is a FreeCAD workbench written in Python. Installing it means putting its folder into FreeCAD’s Mod folder; there is nothing to compile.

Requirements

FreeCAD

1.0 or newer (developed and tested on 1.1)

Qt bindings

PySide6, which FreeCAD 1.1 bundles

Python packages

none beyond what FreeCAD ships; numpy, also bundled, makes Monte Carlo about 50 times faster

Operating system

Windows, Linux or macOS (day-to-day testing is on Windows)
Not sure which FreeCAD you have? Open Help  About FreeCAD. Katydid needs version 1.0 or later.

Find your Mod folder

Every FreeCAD user has a personal Mod folder for workbenches. The quickest way to find it is to ask FreeCAD:

  1. Open View  Panels  Python console.

  2. Type the following and press Enter:

    App.getUserAppDataDir()

  3. Your Mod folder is the Mod sub-folder of the path it prints. Create it if it does not exist.

Typical locations:

Windows, FreeCAD 1.1

%APPDATA%\FreeCAD\v1-1\Mod

Windows, FreeCAD 1.0

%APPDATA%\FreeCAD\Mod

Linux

~/.local/share/FreeCAD/Mod (FreeCAD 1.1 may use a v1-1 sub-folder, as on Windows)

macOS

~/Library/Application Support/FreeCAD/Mod

Option A: clone with Git (recommended)

Cloning makes updates a single command.

cd "<your Mod folder>"
git clone https://github.com/Foadsf/Katydid.git

To update later:

cd "<your Mod folder>/Katydid"
git pull

Option B: download a ZIP

  1. On the GitHub page, choose Code then Download ZIP.

  2. Unzip it into your Mod folder.

  3. Rename the folder from Katydid-main to Katydid.

Option C: FreeCAD’s Addon Manager

The Addon Manager can install from any Git repository you add to its list:

  1. Open Edit  Preferences  Addon Manager.

  2. Under Custom repositories, add https://github.com/Foadsf/Katydid with branch main.

  3. Open Tools  Addon manager, find Katydid and install it.

The Addon Manager then also tells you when updates are available.

Check that it works

  1. Restart FreeCAD.

  2. Pick Katydid in the workbench drop-down (or View  Workbench  Katydid).

  3. The Katydid canvas opens as a floating window, and a Katydid menu and toolbar appear.

  4. Choose Examples  Row of boxes on the canvas toolbar. Four red boxes should appear in the 3D view.

If they do, you are ready for the quick start.

FreeCAD with the Katydid canvas floating over the 3D view

Uninstall

Close FreeCAD and delete the Katydid folder from your Mod folder. Files you saved keep their Katydid definitions; they simply are not used until Katydid is installed again.

If something goes wrong

See Troubleshooting. The most common cause is a folder nested one level too deep (Mod/Katydid/Katydid/InitGui.py): InitGui.py must sit directly in Mod/Katydid.