cutPolylineByGrid

From-v3.2

Subdivides a polyline by intersecting with a uniform grid.

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

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

Usage

cutPolylineByGrid(positions, [options]);

Arguments:

  • positions (Array|TypedArray) - a flat array of the vertex positions that define the polyline.
  • 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.
    • gridResolution (Number, optional) - the grid size. Default 10.
    • gridOffset (Array, optional) - the grid offset in [x, y]. Default [0, 0] i.e. the grid starts from the coordinate origin.
    • broken (Boolean, optional) - if true, the polyline is broken into multiple polylines at the subdivision points. If false, subdivision points are inserted into the original polyline. Default false.

Returns:

A polyline or an array of polylines, depending on the broken option. Each polyline is represented by a positions array that uses the same vertex size as the input.