使用bufferGeometry获取THREE.js Points对象中顶点的屏幕坐标

var geometry = new THREE.BufferGeometry();

var positions = new Float32Array([
    // 顶点坐标数据
]);
geometry.setAttribute('position', new THREE.BufferAttribute(positions, 3));

var worldPosition = new THREE.Vector3();

var projector = new THREE.Projector();
var screenPosition = new THREE.Vector3();

// 循环遍历每个顶点
for (var i = 0; i < positions.length; i += 3) {
    // 获取顶点的世界坐标
    worldPosition.fromArray(positions, i);

    // 将世界坐标转换为屏幕坐标
    screenPosition.copy(worldPosition);
    screenPosition.project(camera); // camera为THREE.PerspectiveCamera对象

    // 屏幕坐标范围是[-1, 1]，需要将其转换为屏幕像素坐标
    var x = (screenPosition.x + 1) * canvasWidth / 2;
    var y = (1 - screenPosition.y) * canvasHeight / 2;

    // 在控制台输出顶点的屏幕坐标
    console.log('顶点', i / 3, '的屏幕坐标为：', x, y);
}