
    let interactionBox = null;
    let leftInteractionBox = null;
    let rightInteractionBox = null;

    // WebGL scene globals.
    let gl = null;
    let renderer = null;
    let scene = new Scene();
    scene.addNode(new Gltf2Node({ url: './media/gltf/space/space.gltf' }));
    scene.addNode(new SkyboxNode({ url: './media/textures/milky-way-4k.png' }));
    
    function createBoxPrimitive(r, g, b) {	
      let boxBuilder = new BoxBuilder();	
      boxBuilder.pushCube([0, 0, 0], 1);	
      let boxPrim