javascript - Drawing a Line3 in Threejs -

i want draw line3 in threejs , here code it:

start = new three.vector3(20, 10, 0);  end = new three.vector3(200, 100, 0); var line  = new three.line3(start, end);    scene.add(line); 

the code doesn't give error doesn't draw line either. in same program, have sphere:

   var initscene = function () {    window.scene = new three.scene();     window.renderer = new three.webglrenderer({       alpha: true     });      window.renderer.setclearcolor(0x000000, 0);     window.renderer.setsize(window.innerwidth, window.innerheight);      window.renderer.domelement.style.position = 'fixed';     window.renderer.domelement.style.top = 0;     window.renderer.domelement.style.left = 0;     window.renderer.domelement.style.width = '100%';     window.renderer.domelement.style.height = '100%';      document.body.appendchild(window.renderer.domelement);      var directionallight = new three.directionallight( 0xffffff, 1 );     directionallight.position.set( 0, 0.5, 1 );     window.scene.add(directionallight);      window.camera = new three.perspectivecamera(45, window.innerwidth / window.innerheight, 1, 1000);     window.camera.position.fromarray([0, 150, 700]);     window.camera.lookat(new three.vector3(0, 160, 0));      window.addeventlistener('resize', function () {        camera.aspect = window.innerwidth / window.innerheight;       camera.updateprojectionmatrix();       renderer.setsize(window.innerwidth, window.innerheight);       renderer.render(scene, camera);      }, false);      scene.add(camera);      // set sphere vars     var radius = 50,     segments = 16,     rings = 16;      // create new mesh     // sphere geometry - cover     // spherematerial next!     var spherematerial =     new three.meshlambertmaterial(     {       color: 0xcc0000     });     var sphere = new three.mesh(      new three.spheregeometry(     radius,     segments,     rings),       spherematerial);      // add sphere scene     scene.add(sphere);      start = new three.vector3(20, 10, 0);      end = new three.vector3(200, 100, 0);     var line  = new three.line3(start, end);        scene.add(line);     renderer.render(scene, camera);     };      initscene(); 

i see sphere on screen. can please tell me wrong?

adlads (a day late , dollar short):
http://threejs.org/docs/

line3 1 of many math objects of three.js can used compute geometric stuff. others are: box2 box3 color euler frustum line3 math matrix3 matrix4 plane quaternion ray sphere spline triangle vector2 vector3 vector4

say had "line", line3 object , "plane", plane object. check if line intersected plane doing plane.intersectsline(line). give true or false.

none of these math objects (including line3's) object3d's, things rendered.

here's scoop:
1) make scene, camera, , renderer.
2) add object3d's scene.
2a) object3d's can points, lines, or meshes.
2b) points, lines, , meshes made of geometries , materials.
2c1) points , lines, geometries contain vertices(vector3's) , faces(face3's). "vertices.push" or "faces.push".
2c2) meshes, geometries can be: box circle cylinder dodecahedron extrude icosahedron lathe octahedron parametric plane polyhedron ring shape sphere tetrahedron text torus torusknot tube
3) "renderer.render(scene, camera)".

thanks question. straightened me out.