Javascript Can'；t在树内使用全局变量。enumNodeFragments（）委托

我试图通过fragId保存元素的旧材质，但无法执行此操作，因为无法访问tree.enumNodeFragments（）文档或窗口的内部

    highlight(externalId, color, dict) {
    let viewer = this.viewer;
    var dbId = dict[externalId];


    let myMaterial = this.createMaterial(color);

    // used to rescale and remove the z-fighting
    let scaleRatio = 1.005; // this was determined as optimal through visual inspection

    var tree = NOP_VIEWER.model.getData().instanceTree;

    document.oldMaterials = {};


    tree.enumNodeFragments(dbId,
        function(fragId) {
         document.oldMaterials[fragId] = viewer.model.getFragmentList().getMaterial(fragId);

            viewer.model.getFragmentList().setMaterial(fragId, myMaterial);


            /* important technique if you want to remove z-fighting */
            let fragProxy = viewer.impl.getFragmentProxy(viewer.model, fragId);
            fragProxy.scale = new THREE.Vector3(scaleRatio, scaleRatio, scaleRatio);
            fragProxy.updateAnimTransform();
        },
        true);

    viewer.impl.invalidate(true);
}

---

document

和

window

都应该在回调函数的范围内可用，但是这不是一个好的做法。尝试在

突出显示功能的范围内定义旧材质的贴图：

function highlight(externalId, color, dict) {
    const viewer = this.viewer;
    const dbId = dict[externalId];
    const myMaterial = this.createMaterial(color);
    // used to rescale and remove the z-fighting
    const scaleRatio = 1.005; // this was determined as optimal through visual inspection
    const tree = NOP_VIEWER.model.getData().instanceTree;
    const oldMaterials = {};

    tree.enumNodeFragments(dbId, function(fragId) {
        oldMaterials[fragId] = viewer.model.getFragmentList().getMaterial(fragId);
        viewer.model.getFragmentList().setMaterial(fragId, myMaterial);
        /* important technique if you want to remove z-fighting */
        const fragProxy = viewer.impl.getFragmentProxy(viewer.model, fragId);
        fragProxy.scale = new THREE.Vector3(scaleRatio, scaleRatio, scaleRatio);
        fragProxy.updateAnimTransform();
    },
    true);

    viewer.impl.invalidate(true);
}

我以前也试过。调用树之后。enumNodeFragments oldMaterials为空。viewer.model.getFragmentList（）.getMaterial（fragId）不是空的。我在tree.enumNodeFragments之后调用console.log（document.oldMaterials）或console.log（window.oldMaterials），在控制台中看到{}（空字典）。正如我提到的，引用全局变量（尤其是
document
），这不是一个好的做法，可能会导致不同的问题。尝试改用本地
oldMaterials
常量，并确保
enumNodeFragments
中的回调函数实际执行。如何确保enumNodeFragments中的回调函数实际执行？我的意思是：确认回调函数实际执行，例如，将
console.log
或
debugger
语句放入其中。