clipPolyline

From-v3.2

Clips a polyline with a bounding box.

import {clipPolyline} from '@math.gl/polygon';

clipPolyline([-10, -10, 10, 10, 30, -10], [0, 0, 20, 20], {size: 2});
// returns [[0, 0, 10, 10, 20, 0]]

The clipping bounds are defined as an orthoganal rectangle on the XY plane. If a 3D polyline is supplied, it is clipped by the extuded volume from the bounding box.

Usage

clipPolyline(positions, bbox, [options]);

Arguments:

  • positions (Array|TypedArray) - a flat array of the vertex positions that define the polyline.
  • bbox (Array) - the bounding box, in [minX, minY, maxX, maxY]
  • options (Object, optional)
    • size (Number) - the number of elements in each vertex. Size 2 will interpret positions as [x0, y0, x1, y1, ...] and size 3 will interpret positions as [x0, y0, z0, x1, y1, z1, ...]. Default 2.
    • startIndex (Number, optional) - the index in positions to start reading vertices. Default 0.
    • endIndex (Number, optional) - the index in positions to stop reading vertices. Default positions.length.

Returns:

An array of polylines that are parts of the original polyline and contained by the given bounding box. Each polyline is represented by a positions array that uses the same vertex size as the input.

If the input polyline is entirely outside of the bounding box, an empty array will be returned.