Three.js: 如何减去几何？

我已经找到了答案-不确定这是否是最好的方法，但它是否有效。

我先顺时针添加外部几何图形，然后将位逆时针添加到路径，然后再转换为要拉伸的形状。

        var path = new THREE.Path();
        // outer clockwise
        path.moveTo(-10, 10);
        path.lineTo(10, 10);
        path.lineTo(10, -10);
        path.lineTo(-10, -10);
        path.lineTo(-10, 10);
        // inner anti-clockwise
        path.moveTo(-5, 5);
        path.lineTo(-5, -5);
        path.lineTo(-2, -5);
        path.lineTo(-2, 5);
        path.lineTo(-5, 5);
        // inner anti-clockwise
        path.moveTo(2, 5);
        path.lineTo(2, -5);
        path.lineTo(5, -5);
        path.lineTo(5, 5);
        path.lineTo(2, 5);

        var height = 20;
        var shapes = path.toShapes();
        var solid = new THREE.ExtrudeGeometry(shapes, { amount: height, bevelEnabled: false });
        var mesh = new THREE.Mesh(solid, materials['building']);
        mesh.position.y = height;
        mesh.rotation.x = 90 * Math.PI * 2 / 360;
        scene.add(mesh);

您还可以使用以下命令：
http://learningthreejs.com/blog/2011/12/10/constructive-solid-geometry-with-csg-js/