Babylon.jsで3D共起ネットワーク的なことをしたい

var createScene = function () {
    const scene = new BABYLON.Scene(engine);

    // カメラとライトを設定
    const camera = new BABYLON.ArcRotateCamera("camera1", Math.PI / 2, Math.PI / 4, 10, new BABYLON.Vector3(0, 0, 0), scene);
    camera.attachControl(canvas, true);
    const light = new BABYLON.HemisphericLight("light1", new BABYLON.Vector3(1, 1, 0), scene);

    // 物理エンジンを有効化
    scene.enablePhysics(new BABYLON.Vector3(0, 0, 0), );

    // 球体を作成
    const sphere1 = BABYLON.MeshBuilder.CreateSphere("sphere1", { diameter: 1 }, scene);
    sphere1.position = new BABYLON.Vector3(-2, 0, 0);
    sphere1.physicsImpostor = new BABYLON.PhysicsImpostor(sphere1, BABYLON.PhysicsImpostor.SphereImpostor, { mass: 1, restitution: 0.9 }, scene);

    const sphere2 = BABYLON.MeshBuilder.CreateSphere("sphere2", { diameter: 1 }, scene);
    sphere2.position = new BABYLON.Vector3(2, 0, 0);
    sphere2.physicsImpostor = new BABYLON.PhysicsImpostor(sphere2, BABYLON.PhysicsImpostor.SphereImpostor, { mass: 1, restitution: 0.9 }, scene);

    // SpringJoint を作成
    const springJoint = new BABYLON.PhysicsJoint(BABYLON.PhysicsJoint.SpringJoint, {
        length: 2,
        stiffness: 10,
        damping: 0.7
    });

    // 球体をジョイントで接続
    sphere1.physicsImpostor.addJoint(sphere2.physicsImpostor, springJoint);

    // 球体間に線を引く
    let line = BABYLON.MeshBuilder.CreateLines("line", {points: [sphere1.position, sphere2.position], updatable: true }, scene);

    // シーンを毎フレーム更新
    scene.registerBeforeRender(function () {
        line = BABYLON.MeshBuilder.CreateLines("line", {
            points: [sphere1.position, sphere2.position], instance: line
        });
    });

    const addDragBehavior = (mesh) => {
        var pointerDragBehavior = new BABYLON.PointerDragBehavior({});
        mesh.addBehavior(pointerDragBehavior);
    }
    addDragBehavior(sphere1)
    addDragBehavior(sphere2)


    return scene;
};

    scene.registerBeforeRender(function () {
        const minDistance = 10; // 反発力を適用する最小距離
        const repulsionConstant = minDistance * minDistance; // 反発力の定数

        // 球体同士の反発力
        const keys = Object.keys(spheres)
        keys.forEach((keyA, indexA) => {
            const sphereA = spheres[keyA]
            for (let indexB = indexA + 1; indexB < keys.length; indexB++) {
                const sphereB = spheres[keys[indexB]];

                const distanceVec = sphereA.position.subtract(sphereB.position);
                const distance = distanceVec.length();

                // 反発力
                if (distance < minDistance) {
                    const repulsionForce = distanceVec.normalize().scale(repulsionConstant / (distance * distance));
                    sphereA.physicsImpostor.applyForce(repulsionForce, sphereA.position);
                    sphereB.physicsImpostor.applyForce(repulsionForce.scale(-1), sphereB.position);
                }
            }
        });
    
        // ...

    });

const text = node.name;
const font = "bold 44px monospace";
const dynamicTexture = new BABYLON.DynamicTexture("DynamicTexture", { width: 512, height: 256 }, scene, true);

// 背景透過 
dynamicTexture.hasAlpha = true;

// 背景透過： "transparent"
dynamicTexture.drawText(text, null, null, font, "black", "transparent", true, true);

const material = new BABYLON.StandardMaterial("TextMaterial", scene);
material.diffuseTexture = dynamicTexture;

// 背景透過
material.useAlphaFromDiffuseTexture = true;

material.backFaceCulling = false;

const plane = BABYLON.MeshBuilder.CreatePlane("TextPlane", { width: 3, height: 1.5 }, scene);
plane.material = material;

// 正面方向が逆なので反転
plane.scaling.x = -1;

// テキストを正面に向ける
keys.forEach((key) => {
    const sphere = spheres[key].sphere;
    const plane = spheres[key].plane;

    // カメラと球体の中心とのベクトルを計算
    const direction = sphere.position.subtract(camera.position).normalize();
    
    // テキストを球体の表面に配置（球体の半径を考慮）
    const sphereRadius = sphere.getBoundingInfo().boundingSphere.radiusWorld;
    plane.position = sphere.position.subtract(direction.scale(sphereRadius));
    plane.lookAt(camera.position);
});

scene.registerBeforeRender(function () {
    // ...

    // ダブルクリックした球体にフォーカス
    if (animating) {
        camera.target = BABYLON.Vector3.Lerp(camera.target, targetPosition, 0.01);
        if (BABYLON.Vector3.DistanceSquared(camera.target, targetPosition) < 0.01) {
            animating = false; // 目標に十分近づいたらアニメーションを停止
        }
    }

});

// ダブルクリックした球体にフォーカス
let targetPosition = camera.position;
let animating = false;
window.addEventListener("dblclick", function(evt) {
    const pickResult = scene.pick(scene.pointerX, scene.pointerY);
    if (pickResult.hit) {
        targetPosition = pickResult.pickedMesh.position;
        animating = true; // アニメーション開始
    }
});

plane.isPickable = false;

// 選択した球体に接続された線の色を変える
const pickedName = pickResult.pickedMesh.name
lines.forEach(line => {
    if (line.line.name.includes(pickedName)) {
        line.line.material.diffuseColor = new BABYLON.Color3(1, 0, 1);
    } else {
        line.line.material.diffuseColor = new BABYLON.Color3(1, 1, 1);
    }
})