three.js/examples/jsm/math/Capsule.js

import {
	Vector3
} from 'three';

class Capsule {

	constructor( start = new Vector3( 0, 0, 0 ), end = new Vector3( 0, 1, 0 ), radius = 1 ) {

		this.start = start;
		this.end = end;
		this.radius = radius;

	}

	clone() {

		return new Capsule( this.start.clone(), this.end.clone(), this.radius );

	}

	set( start, end, radius ) {

		this.start.copy( start );
		this.end.copy( end );
		this.radius = radius;

	}

	copy( capsule ) {

		this.start.copy( capsule.start );
		this.end.copy( capsule.end );
		this.radius = capsule.radius;

	}

	getCenter( target ) {

		return target.copy( this.end ).add( this.start ).multiplyScalar( 0.5 );

	}

	translate( v ) {

		this.start.add( v );
		this.end.add( v );

	}

	checkAABBAxis( p1x, p1y, p2x, p2y, minx, maxx, miny, maxy, radius ) {

		return (
			( minx - p1x < radius || minx - p2x < radius ) &&
			( p1x - maxx < radius || p2x - maxx < radius ) &&
			( miny - p1y < radius || miny - p2y < radius ) &&
			( p1y - maxy < radius || p2y - maxy < radius )
		);

	}

	intersectsBox( box ) {

		return (
			this.checkAABBAxis(
				this.start.x, this.start.y, this.end.x, this.end.y,
				box.min.x, box.max.x, box.min.y, box.max.y,
				this.radius ) &&
			this.checkAABBAxis(
				this.start.x, this.start.z, this.end.x, this.end.z,
				box.min.x, box.max.x, box.min.z, box.max.z,
				this.radius ) &&
			this.checkAABBAxis(
				this.start.y, this.start.z, this.end.y, this.end.z,
				box.min.y, box.max.y, box.min.z, box.max.z,
				this.radius )
		);

	}

}

export { Capsule };