Inca

A free, open-source 3D modeling, animation and rendering application for the desktop

Website and downloads: https://incacad.com

Contributing

Write an issue on the gh issues page

See FEATURES.md for the full feature list.

Download and run

Go to the Releases page and open the newest release. Under Assets, download the file for your computer.

Windows

1. Download Inca-<version>-win-x64-portable.exe.
2. Double-click it. You don't need to install anything.
3. If Windows shows "Windows protected your PC", click More info, then Run anyway. Windows shows this for apps from small developers. It doesn't mean anything is wrong.

You can also download the .zip instead. Unzip it, then double-click Inca.exe inside the folder.

Linux

1. Download Inca-<version>-linux-x86_64.AppImage.
2. Right-click the file, open Properties → Permissions, and tick Allow executing file as program. In a terminal you can do the same with chmod +x Inca-*.AppImage.
3. Double-click it to start Inca.

If it doesn't open, start it from a terminal so you can see the error:

./Inca-*.AppImage --no-sandbox

On Ubuntu 22.04 or newer, if you get an error about FUSE, run sudo apt install libfuse2 once. On Ubuntu 24.04 the package is called libfuse2t64.

macOS

1. Download Inca-<version>-mac-arm64.dmg for Apple Silicon Macs (M1 and newer), or Inca-<version>-mac-x64.dmg for older Intel Macs. To check which you have, open the Apple menu → About This Mac: "Chip: Apple M…" means Apple Silicon.
2. Open the .dmg and drag Inca into Applications.
3. The first time, macOS says it can't check Inca for malware, because Inca isn't registered with Apple (that costs $99 a year). Click Done, then open System Settings → Privacy & Security, scroll down and click Open Anyway next to the message about Inca. On macOS 14 or older you can instead right-click Inca in Applications and choose Open. You only need to do this once.

Run from source

1. Install Node.js (version 18 or newer)

Ubuntu / Linux Mint: sudo apt install nodejs npm is enough. (If apt update complains about one broken third-party repository, such as an old apt.kitware.com entry, that only affects that repository; you can disable it in Software Sources.)

Inca runs on Electron, which is installed through npm, so you need a recent Node.js. Check with node -v.

• Linux Mint / Ubuntu / Debian: the distro's nodejs package is often too old. Use NodeSource or nvm:

  curl -fsSL https://deb.nodesource.com/setup_22.x | sudo -E bash -
  sudo apt-get install -y nodejs
  

  or curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.1/install.sh | bash, open a new terminal, then nvm install 22.
• Windows / macOS: install the LTS version from https://nodejs.org.

2. Install the dependencies (this also installs Electron)

In a terminal, inside the inca folder (the one containing package.json):

npm install

This downloads Electron, three.js and the other libraries into node_modules/, then copies the three.js add-ons into vendor/three-addons/ (the app also recreates that folder on start-up if it is missing).

If Electron did not get installed (for example npm start says electron: not found), install it explicitly:

npm install --save-dev electron@38.8.6

If its download was blocked or interrupted, delete node_modules/electron and run the command again.

3. Start Inca

npm start

Linux: if Electron exits with an error about chrome-sandbox / "SUID sandbox helper", either fix the helper's permissions once:

sudo chown root node_modules/electron/dist/chrome-sandbox && sudo chmod 4755 node_modules/electron/dist/chrome-sandbox

or start without the sandbox: npm start -- --no-sandbox.

Blank window?

If the window opens but stays empty or shows "Inca could not start", the libraries are incomplete. Run npm install again in the inca folder, then npm start. Ctrl+Shift+F12 opens the developer tools, where the Console tab shows the exact file that failed to load.

Build installers

Works with Node.js 18 or newer (including Ubuntu / Linux Mint's own nodejs 18.19 package). If you get ERR_REQUIRE_ESM ... @noble/hashes/blake2.js, your node_modules still has a newer electron-builder from an older copy of Inca: run rm -rf node_modules package-lock.json && npm install.

npm run dist:linux          # dist/Inca-<ver>-linux-x86_64.AppImage
npm run dist:win            # dist/Inca-<ver>-win-x64.zip (unzip on Windows, run Inca.exe)
npm run dist:win-portable   # dist/Inca-<ver>-win-x64-portable.exe (single file, just double-click)
npm run dist:win-installer  # NSIS setup .exe - build this on Windows, or on Linux with Wine installed
npm run dist:mac            # run on macOS

Each build runs on its own, so npm run dist:linux && npm run dist:win builds both.

Tests

npm test                                   # geometry kernel + editor maths
INCA_TEST=script.js INCA_SHOTS=out npx electron .   # drive the real app with a script and capture screenshots

Layout

• main.js, preload.js — Electron main process & native bridge (files, dialogs, prefs)
• src/js/core — engine: scene graph & construction history (scene.js), polygon kernel (polymesh.js, ops.js), primitives, curves, materials, animation, undo, MEL interpreter, file I/O, rigging, deformers, constraints, dynamics, booleans
• src/js/ui — interface: viewports, menus, shelves, panels, editors and tools
• docs/ui-contract.md — how UI modules plug into the app

MIT licensed. Built with three.js, three-mesh-bvh, three-gpu-pathtracer, three-bvh-csg and Electron.