three.js/examples/js/geometries/BoxLineGeometry.js

THREE.BoxLineGeometry = function ( width, height, depth, widthSegments, heightSegments, depthSegments ) {

	THREE.BufferGeometry.call( this );

	width = width || 1;
	height = height || 1;
	depth = depth || 1;

	widthSegments = Math.floor( widthSegments ) || 1;
	heightSegments = Math.floor( heightSegments ) || 1;
	depthSegments = Math.floor( depthSegments ) || 1;

	var widthHalf = width / 2;
	var heightHalf = height / 2;
	var depthHalf = depth / 2;

	var segmentWidth = width / widthSegments;
	var segmentHeight = height / heightSegments;
	var segmentDepth = depth / depthSegments;

	var vertices = [];

	var x = - widthHalf, y = - heightHalf, z = - depthHalf;

	for ( var i = 0; i <= widthSegments; i ++ ) {

		vertices.push( x, - heightHalf, - depthHalf, x, heightHalf, - depthHalf );
		vertices.push( x, heightHalf, - depthHalf, x, heightHalf, depthHalf );
		vertices.push( x, heightHalf, depthHalf, x, - heightHalf, depthHalf );
		vertices.push( x, - heightHalf, depthHalf, x, - heightHalf, - depthHalf );

		x += segmentWidth;

	}

	for ( var i = 0; i <= heightSegments; i ++ ) {

		vertices.push( - widthHalf, y, - depthHalf, widthHalf, y, - depthHalf );
		vertices.push( widthHalf, y, - depthHalf, widthHalf, y, depthHalf );
		vertices.push( widthHalf, y, depthHalf, - widthHalf, y, depthHalf );
		vertices.push( - widthHalf, y, depthHalf, - widthHalf, y, - depthHalf );

		y += segmentHeight;

	}

	for ( var i = 0; i <= depthSegments; i ++ ) {

		vertices.push( - widthHalf, - heightHalf, z, - widthHalf, heightHalf, z );
		vertices.push( - widthHalf, heightHalf, z, widthHalf, heightHalf, z );
		vertices.push( widthHalf, heightHalf, z, widthHalf, - heightHalf, z );
		vertices.push( widthHalf, - heightHalf, z, - widthHalf, - heightHalf, z );

		z += segmentDepth;

	}

	this.setAttribute( 'position', new THREE.Float32BufferAttribute( vertices, 3 ) );

};

THREE.BoxLineGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );
THREE.BoxLineGeometry.prototype.constructor = THREE.BoxLineGeometry;