cascade-core

Reusable CAD modeling engine built on OpenCascade WASM. Evaluate CAD code in a Web Worker and get triangle mesh data back — no GUI dependencies.

This is the headless engine that powers Cascade Studio. Use it to embed parametric CAD modeling in any web application.

Install

npm install cascade-core

Quick Start

import { CascadeEngine } from 'cascade-core';

const engine = new CascadeEngine({ workerUrl: './cascade-worker.js' });
await engine.init();

const result = await engine.evaluate(`
  let box = Box(20, 20, 20);
  FilletEdges(box, 3, Edges(box).max([0,0,1]).indices());
`, { guiState: { 'Cache?': true } });

// result.meshData = { faces: [...], edges: [...] }
// Render with Three.js, Babylon.js, or any WebGL framework

Copy cascade-worker.js, cascadestudio.wasm, and fonts/ from node_modules/cascade-core/dist/ to your static assets directory.

Examples

These are all built with the cascade-core standard library — try them live:

API

new CascadeEngine({ workerUrl })

Create an engine instance. workerUrl is the path to the bundled worker file.

engine.init() → Promise

Load the worker and OpenCascade WASM. Resolves when ready.

engine.evaluate(code, options?) → Promise<{ meshData, sceneOptions }>

Evaluate CAD code and return triangulated mesh data.

• code — JavaScript string using the standard library (Box, Sphere, Sketch, etc.)
• options.guiState — slider/checkbox state object
• options.maxDeviation — mesh resolution (default 0.1)
• Returns { meshData: { faces, edges }, sceneOptions }

engine.meshHistoryStep(index, maxDeviation?) → Promise

Triangulate a specific modeling history step.

engine.exportSTEP() → Promise<string>

Export the current shape as STEP file text.

engine.on(event, handler) / engine.off(event, handler)

Listen for events: log, error, Progress, resetWorking, modelHistory, addSlider, addButton, addCheckbox, addTextbox, addDropdown, saveFile.

engine.isReady / engine.isWorking

Boolean status properties.

engine.dispose()

Terminate the worker and clean up.

Standard Library

The evaluated code has access to these functions:

• Primitives: Box, Sphere, Cylinder, Cone, Circle, Polygon, Text3D, BSpline, Wedge
• Sketch: new Sketch([x,y], plane?).LineTo().Fillet().ArcTo().BSplineTo().End().Face()
• Transforms: Translate, Rotate, Scale, Mirror
• Booleans: Union, Difference, Intersection
• Operations: Extrude, Revolve, Loft, Pipe, Offset, FilletEdges, ChamferEdges
• Selectors: Edges(shape).ofType().parallel().max().min().indices()
• Measurement: Volume, SurfaceArea, CenterOfMass
• GUI: Slider, Checkbox (values come from guiState)

See the full TypeScript definitions in types/StandardLibraryIntellisense.ts.

OpenSCAD

import { OpenSCADTranspiler } from 'cascade-core';

const transpiler = new OpenSCADTranspiler();
const jsCode = transpiler.transpile(`
  difference() {
    cube(20, center=true);
    sphere(r=12);
  }
`);
const result = await engine.evaluate(jsCode);

Credits

• opencascade.js (CAD Kernel — OCCT 8.0.0 RC4 via Embind)
• opentype.js (Font Parsing for Text3D)
• potpack (Texture Atlas Packing)

License

MIT