在three.js

Question

我正在尝试在three.js中创建一个10 x 10网格的椅子obj文件。我有一个功能，将添加一个椅子到场景。但是，当我尝试将对象返回到循环函数以创建更多它们时，我被告知“undefined不是一个对象。它似乎没有保存它应该返回的对象。这是什么我有。

function getChair(){
    var loader = new THREE.OBJLoader();
    var textureLoader = new THREE.TextureLoader();

    loader.load(‘assets/models/theatreChair.obj’, function (object) {
        var colorMap = textureLoader.load(‘assets/textures/chairDiffuseColor.png’);
        var bumpMap = textureLoader.load(‘assets/textures/chairBumpTextures.png’);
        var faceMaterial = new THREE.MeshStandardMaterial(‘rgb(255,255,255)’);

        object.traverse(function(child) {

            child.material = faceMaterial;
            faceMaterial.roughness = 1;
            faceMaterial.map = colorMap;
            faceMaterial.bumpMap = bumpMap;
            faceMaterial.roughnessMap = bumpMap;
            faceMaterial.metalness = 0;
            faceMaterial.bumpScale = 0.1;
        });
        // scene.add(object) -- This works. It adds a chair at 0,0,0. Use scroll wheel to see it.
        return object; // Should return the chair object, right?
    });
}

function getChairGrid(amount, seperationMultiplier){
   var group = new THREE.Group();

   for (var i=0; i<amount; i++) {
       var obj = getChair();
       obj.position.x = i * seperationMultiplier; // Fails here. “undefined is not an object (evaluating ‘obj.position’)”
       obj.position.y = obj.geometry.parameters.height/2;
       group.add(obj);
       for (var j = 1; j<amount; j++){
           var obj = getChair();
           obj.position.x = i * seperationMultiplier;
           obj.position.y = obj.geometry.parameters.height/2;
           obj.position.z = j * seperationMultiplier;
           group.add(obj);

       }
   }

   group.position.x = -(seperationMultiplier * (amount-1))/2;
   group.position.z = -(seperationMultiplier * (amount-1))/2;

   return group;
}