LuaCAD is a scripting library which uses OpenSCAD as engine to create 2D and 3D objects.

Simple Model

The LuaCAD library creates OpenSCAD code which is then used to create DXF, SVG, or STL files.

• Install OpenSCAD ( macOS, Linux, Windows )
• Install LuaJIT
  • macOS: brew install luajit
  • Ubuntu: sudo apt-get install luajit
  • Linux
  • Windows
• Download the project
• Unzip the project
• Change into the new directory: cd ./LuaCAD-main
• Create your <name>.lua model file (including a ...:export("out.scad") line)
• Execute code with:

  bin/luacad <name>.lua

• Open the generated out.scad file with OpenSCAD

OpenSCAD:

module my_cube() {
 cube(size=[1,2,3]);
}
module my_sphere(radius) {
 translate([5,0,0]) sphere(r = radius);
}
union() {
 my_cube();
 my_sphere(2);
}

LuaCAD:

require("luacad")
my_cube = cube { size = { 1, 2, 3 } }
function my_sphere(radius)
 return sphere({ r = radius }):translate(5, 0, 0)
end
model = my_cube + my_sphere(2)
model:export("simple.scad")

FennelCAD:

(require :luacad)
(local my_cube (cube {:size [1 2 3]}))
(print "cube type:" (type my_cube)) ;print info
(print "cube scad_content:\n" my_cube.scad_content)
(fn my_sphere [radius]
 (: (sphere {:r radius}) :translate [5 0 0]))
(local model (+ my_cube (my_sphere 4)))
(export "/tmp/simple.scad" model)

In comparison to OpenSCAD, LuaCAD provides several additional functions that make it easier to create complex models:

• 2D Objects
  • ellipse()
  • regular_polygon()
• 3D Objects
  • cone() (can use cylinder with different radii)
  • prism()
  • wedge()
  • torus()
  • surface()
• Extrusions
  • rotate_extrude() with angle parameter
• Mathematical/Programming
  • Most math functions (cross(), norm(), trigonometric functions)
  • List operations (len(), each, range())
• Special
  • import_3mf(), rands(), search()
  • scad(string) - Insert verbatim OpenSCAD code

The OpenSCAD language is limited and has several issues:

• Confusing functions vs modules
• Weird variable scoping
• Not a well establised programming language
  • Bad editor support
  • Limited documentation
  • Limited libraries
  • Bad error messages
  • Bad performance

Therefore, a real programming language should be used and it should ideally be interpreted and have good operator overloading support

• Julia - Too complex
• Python - Too slow and while easy to get started, hard to master

... and the winner is Lua 🏆

• Powerful
• Consistent
• Fast
• Well established
• Easily embeddable and could therefore be directly integrated into OpenSCAD or a new CAD software
• Similar syntax to OpenSCAD language
• Already used in other CAD software like LibreCAD and Autodesk Netfabb

• SCAD
• 3MF
• STL
• DXF
• OBJ
• SVG
• WRL

• Full support or Belfry OpenSCAD Library v2
• Support for exporting .png files
• Implement "LuaCAD Studio" GUI desktop app

Other CAD software that support programmatic creation of 3D models:

• BlocksCAD - Blockly-based CAD software
• Flowscad - Rust interface to OpenSCAD in the spirit of SolidPython
• FreeCAD - Python scripting
• HelloTriangle - 3D modeling with Python scripting.
• ImplicitCAD - Haskell-based CAD software
• LibreCAD - Lua scripting
• Liquid CAD - 2D constraint-solving CAD for rapid prototyping
• ManifoldCAD - Online CAD software using JavaScript
• OpenSCAD Rust - Rust implementation of the OpenSCAD virtual machine
• OpenSCAD - OpenSCAD language
• Rust Scad - Library for generating OpenSCAD code using Rust
• scad_tree - Rust solid modeling library that generates OpenSCAD code
• ScalaCad - Constructive Solid Geometry in Scala
• SolidRS - Rust library to generate OpenSCAD models
• https://willpatrick.xyz/technology/2025/04/23/teaching-llms-how-to-solid-model.html

The initial work was done by Michael Lutz at thechillcode/Lua_CAD.

• AD4SM
• cadCAD
• ConstructiveGeometry
• [Descartes]
• FinEtoolsVoxelMesher
• MeshIO
• Modia3D
• OpticSim CSG
• [OpticSim]

Antyos/vscode-openscad: An OpenSCAD extension for VS Code https://github.com/Antyos/vscode-openscad