更新爆炸图例子

src/GeUtils.ts

@@ -1,5 +1,5 @@
 import * as THREE from 'three';
-import { Geometry, Vector, Vector2, Vector3 } from 'three';
+import { Geometry, Vector, Vector2, Vector3, Box3 } from 'three';
 import { Matrix2 } from './Matrix2';
 
 
@@ -168,51 +168,47 @@ export function midPtCir(v1: THREE.Vector3, v2: THREE.Vector3)
     return v1.clone().add(midLine);
 }
 
+/**
+ * 获得Three对象的包围盒.
+ * @param obj 
+ * @param [updateMatrix] 是否应该更新对象矩阵
+ * @returns box 
+ */
 export function GetBox(obj: THREE.Object3D, updateMatrix?: boolean): THREE.Box3
 {
+    let box = new Box3();
     if (updateMatrix) obj.updateMatrixWorld(false);
-    if (obj.hasOwnProperty("geometry"))
+    if (!obj.visible) return box;
+
+    obj.traverse(o =>
     {
-        let geo = obj["geometry"];
-        if (geo instanceof THREE.Geometry || geo instanceof THREE.BufferGeometry)
+        //因为实体Erase时,实体仍然保存在Scene中.
+        if (o.visible === false)
+            return;
+
+        //@ts-ignore
+        let geo = o.geometry as BufferGeometry;
+        if (geo)
         {
             if (!geo.boundingBox)
                 geo.computeBoundingBox();
-            return geo.boundingBox.clone().applyMatrix4(obj.matrixWorld);
+            box.union(geo.boundingBox.clone().applyMatrix4(o.matrixWorld));
         }
-    }
-    else if (obj.children.length > 0)
-    {
-        let box = obj.children.reduce((sumBox, itemObj) =>
-        {
-            let itemBox = GetBox(itemObj);
-            if (itemBox)
-                sumBox.union(itemBox);
-            return sumBox;
-        }, new THREE.Box3())
-        // if (box) box.applyMatrix4(obj.matrixWorld);
-        return box;
-    }
-    else
-        return null;
+    });
+
+    return box;
 }
 
 export function GetBoxArr(arr: Array<THREE.Object3D>): THREE.Box3
 {
-    if (arr.length == 0)
+    let box = new Box3();
+    for (let o of arr)
     {
-        return null;
+        let b = GetBox(o);
+        if (!b.isEmpty())
+            box.union(b);
     }
-    return arr.map(o =>
-    {
-        return GetBox(o);
-    }).filter(o =>
-    {
-        return o;
-    }).reduce((sumBox: THREE.Box3, objBox: THREE.Box3) =>
-    {
-        return sumBox.union(objBox)
-    }, new THREE.Box3());
+    return box;
 }
 
 export function MoveMatrix(v: THREE.Vector3): THREE.Matrix4