Replicate

replicate() copies a mated part — or a mated sub-assembly — onto new mate targets. It is the "copy with mates" of other CAD systems, not a geometric pattern: every replica gets the seed's mates re-targeted to its own references, so the four standoffs on a plate each sit in their own hole and move on their own.

In the viewport

1. Mate the first instance the way every copy should be mated — the seed.
2. Click Replicate on the assembly toolbar and pick the seed.
3. The dialog lists the seed's outer mate sides — the connectors or faces on other parts its mates reference. For each replica, pick the replacement for each one.
4. Click Apply. The replicas appear as ordinary rows in the Parts panel, named after the seed with a suffix, marked as replicas.

The code behind it

standoff.part.js

standoff.part.js

import { part, sketch, circle, extrude, chamfer, color, connector } from 'fluidcad/core';

// A Ø8 × 15 standoff with a Ø4 through hole, chamfered on top.
export const standoff = part('Standoff', () => {
    sketch('xy', () => {
        circle([0, 0], 8);
        circle([0, 0], 4);
    });
    const body = extrude(15);
    chamfer(0.5, body.endEdges());
    color('goldenrod');
    // The foot: the face that sits on a mounting hole.
    connector('foot', body.startFaces());
});

standoffs.assembly.js

import { assembly, insert, mate, replicate } from 'fluidcad/core';
import { plate } from './asm-plate.part.js';
import { standoff } from './asm-standoff.part.js';

export const standoffs = assembly('standoffs', () => {
    const base = insert(plate).grounded();

    // The seed: one standoff fastened onto the first mounting hole.
    const first = insert(standoff);
    mate('fastened', base.connectors.hole1, first.connectors.foot);

    // replicate() re-inserts the seed once per row and re-targets its
    // mates. The second argument lists the seed's OUTER mate sides that
    // change per copy (one column: the plate connector); each row gives
    // that column's replacement for one replica. Replicas take the seed's
    // name with a suffix — "Standoff (2)", "Standoff (3)", … — and are
    // ordinary instances from here on.
    replicate(first, [base.connectors.hole1], [
        [base.connectors.hole2],
        [base.connectors.hole3],
        [base.connectors.hole4],
    ]);
});

Signature

replicate(seed, targets, rows)

Argument	Meaning
seed	The handle insert() returned for the instance or sub-assembly to copy.
targets	The seed's outer mate sides that change per replica — one column each. Any outer side not listed stays shared by every replica (a planar mate onto one common base).
rows	One array per replica, one entry per target: rows[k][j] replaces targets[j] in replica k's mates. At least one row.

It returns the replica handles in row order, so const [b, c, d] = replicate(...) lets you name or mate them further.

Rules

• Only mates written before the statement replicate. Mate options (flip, rotate, offset, limits) are copied verbatim.
• Replicas start at the seed's pose and are never grounded — their mates place them.
• A target can be any mate side: instance.connectors.<name>, an assembly connector, or instance.features.<name> for a tangent mate.
• Replicating a sub-assembly re-runs its body with the same parameters; its inner mates come along.