不知道是IBL还是FBO。。感觉应该是FBO实现的

创建

       cubeCamera = new THREE.CubeCamera(0.1, 1000, 256);
        scene.add(cubeCamera);

创建一个用于显示的东西 用个球吧

               var geometry = new THREE.SphereBufferGeometry( 20, 50, 50 );
                var materiall = new THREE.MeshBasicMaterial({
                envMap:cubeCamera.renderTarget.texture
                });
                var sphereMesh = new THREE.Mesh( geometry, materiall );

                sphereMesh.position.y+=50;
                scene.add( sphereMesh );

在render里面先 cubeCamera.update( renderer, scene );

然后才 renderer.render(scene,camera);  requestAnimationFrame(render);