Overview

I love using OpenSCAD but I really miss the power of a full programming language. (I particularly miss data structures.) So, I’ve written this little TypeScript library that generates OpenSCAD files.

Important

Work in Progress This project is very much a work in progress.

My Workflow

• create a TypeScript file that creates a shape and renders it

Example Script

import { cuboid, cylinder, difference, move, union } from '@rossiam/ts3d'

const randomThing = difference(
	union(
		cuboid(100, 50, 25).round({ edges: 'all', radius: 4 }).move(0, -100, 0),
		cylinder(10, 50).chamfer({ radius: 4, edges: 'bottom' }).move(4, 4, 0),
	),
	cuboid(32, 16, 42).round({ radius: 4, edges: 'sides' }).move(20, 100, -1),
)

const variables = {
	'$fn': 60,
	chamfer_radius: 0.6,
}
randomThing.writeCADAndRender({ filename: 'my-awesome-model.scad', variables })

• run deno in watch mode

$ deno run --allow-write --allow-run --watch my-awesome-model.ts

• --allow-write is needed if rendering to .scad with writeCAD

• --allow-run is needed in addition to --allow-write if automatically rendering to stl with writeCADAndRender

  • make changes;

Prerequisites

• deno.com

• openscad.org; need a development snapshot or nightly build from openscad.org/downloads.html#snapshots to render STL

TODO

• 2d shapes: circle, square, polygon, import, projection

• 3d shapes: sphere, finish cube and cylinder, polyhedron, import, linear_extrude, rotate_extrude, surface

• make examples use published version

• TODOs all over the code

• TESTS TESTS TESTS

• maybe be able to run a temporary script that uses fontmetrics or textmetrics to help calculate font size?

• fantasy: output directly to some other format like stl, 3mf, step, obj, or amf maybe

Translating OpenSCAD to ts3d

TODO: much more to explain here

• cube

  • normally use cuboid (for cuboid with sides of varying links)

  • use cube for actual cube

• cylinder

  • cylinder is reserved for a cylinder with ends of the same diameter

  • use frustum for a frustum with different size circles on each end

  • use cone for a cone

Candy

TODO: describe these more fully

• .chamfer and round

• no fillet but you can use difference to subtract a chamfered or rounded shape to get a fillet

• .move

• text3d

Notes

• null or undefined values in most things that take a list of shapes like union or difference are ignored TODO: describe why this is useful

• some idiosyncrasies of OpenSCAD have been removed; some have not

• some of my own idiosyncrasies have certainly found their way in 😂

Pros and Cons

Pros

• full power of TypeScript

• full power of TypeScript (main reason for doing this; counts as at least two pros 😁)

• some idiosyncrasies of OpenSCAD have been fixed

• can have STL files generated automatically on save

Cons

• need to check for errors in two places (mitigated somewhat by extra error checking in TypeScript)

• potentially slower but not noticeable to me

• in OpenSCAD, you can more easily include logic inside modules; in TypeScript you have to do the logic up front or use an Immediately Invoked Function Expression TODO: add example of this

• some idiosyncrasies of OpenSCAD have been fixed (might be confusing especially since there isn’t great documentation for this library yet)

• has its own set of idiosyncrasies

• when dealing with text, there is no way currently to call fontmetrics or textmetrics

Alternatives I’ve Encountered

• Plain ol' trusty OpenSCAD

• Cascade Studio

• JSCAD

• scad-clj using Calva

• openscad-js

• scad-ts / scad-js