Bodies - OpenGeometry

A body is a node in the document that holds a shape. There are three kinds.

Class	`bodyType`	What it is	Made by
`Wire`	`'Wire'`	Lines and arcs, open or closed. No faces.	Rectangle, circle, polyline, profile, arc
`Sheet`	`'Sheet'`	Faces that enclose no volume.	A sweep with `caps: false`
`Solid`	`'Solid'`	Closed faces around a volume.	Cuboid, cylinder, sphere and the other solid primitives; extrude, sweep, revolve

The constructor takes a kind, its parameters and options:

import { OpenGeometry, Solid, Wire, OG_OPERATION_EXTRUDE, OG_PRIMITIVE_CIRCLE } from 'opengeometry';

await OpenGeometry.create(
  { wasmURL: '/opengeometry_bg.wasm' },
  { workerURL: '/tessellation-worker.js' },
);

const circle = new Wire(OG_PRIMITIVE_CIRCLE, { radius: 0.5 }, { ogId: 'post-profile' });
const post = new Solid(OG_OPERATION_EXTRUDE, { profile: circle, distance: 2.4 }, { ogId: 'post' });
console.log(circle.bodyType, post.bodyType, post.ogId);

Identity

Each body has an ogId. Pass your own in the options, or let the SDK make one. Use it to find the body again, for example in a picking result or a STEP report.

Inputs stay separate

An operation reads its inputs when you call it. The result does not follow them later:

The wire that you extruded stays a separate body. Changing it later does not change the solid.
The tools of an operate call stay separate, live solids. Moving or disposing a tool later does not change the target.
A body is drawn only if you add it to the scene.

Shapes, copies and instances

A body points to a shape. Two ways make a second body from the first:

Call	Shape	An edit of one body
`body.duplicate()`	A new copy	Changes that body only
`body.instance()`	Shared	Throws `SharedShape`, unless you pass `{ instances: 'all' }`

getInstanceCount() gives the number of bodies that share the shape. makeUnique() gives a body its own copy, so you can edit it alone. Instances are cheap: the kernel stores the shape and its display mesh once.

Edits

Shape edits change the body in place and give its shape a new revision:

solid.operate(...): booleans and shell.
body.rebuild(kind, params): new parameters. A wire stays a wire and a solid stays a solid. An earlier operate result is gone, so call operate again after it.
body.mirror(plane): a reflection across a plane.

Dispose

Call dispose() on a body or an assembly that you no longer need. A disposed body throws Disposed on every call. If a mark is live, a rollback can bring the body back. clone() gives a display copy for Three.js only, with no kernel shape. copy() throws; use duplicate().

​Identity

​Inputs stay separate

​Shapes, copies and instances

​Edits

​Dispose

Identity

Inputs stay separate

Shapes, copies and instances

Edits

Dispose