origin-offset.md

title	originOffset
description	Shift the local origin by a displacement while preserving shape and topology.
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sidebar	hidden true
head	tag content title originOffset — Code3D TypeScript API reference

Choose a new local zero by a displacement in the input model coordinates.

Example

import {box} from '@code3d/core';

export const bottomZero = box(24, 6, 14).originOffset(0, -3, 0);

Complete example: origins and local transforms.

Signature

model.originOffset(dx: number, dy: number, dz: number): ModelForKind<Elements, Kind>;

Import the functions and named types from @code3d/core.

Displacement and coordinates

dx, dy and dz are finite distances in model units. TypeScript requires all three; the App can fill omitted components with zero while editing.

If the chosen displacement is d, each point changes from p to p - d. A positive origin displacement therefore reduces geometry coordinates on that axis. The example chooses the center of the box's bottom as zero: its Y range changes from [-3, 3] to [0, 6].

Successive offsets add; opposite offsets cancel. The shape and distances between its points do not change. Use originPoint when the desired zero is an existing point reference, or originCenter for the current geometric bounding-box center.

Groups

All models support originOffset, including empty and nested groups. A group is rebased as one already assembled layout. Member spacing and internal placement are retained; the operation does not recenter each member independently.

Value and reference behavior

The operation returns a new model with the same kind and exposed member types. The original value and previously selected references keep their meaning. Topology IDs are preserved. Geometry and named references are transformed together; model.origin and model.frame.origin on the result still refer to its local zero. Origin changes preserve directions, lengths, areas and volumes.

These operations work in the receiver's local coordinates. A relation's offset places a part in a composition; it is a separate operation. For an already related model, its own geometry references in stored placement conditions are transformed consistently. See local coordinates for assembly frame rules.