新增鼠标选择回调事件

src/Viewer.ts

@@ -10,7 +10,7 @@ export class ViewerSettings
 {
   boardMaterial: MeshBasicMaterial = boardMaterial;
   selectMaterial: MeshBasicMaterial = selectMaterial;
-
+  selectByPointCallback: (meshId: number) => void = () => { };
 }
 
 export class Viewer
@@ -211,6 +211,10 @@ export class Viewer
     {
       this.oldMesh = mesh;
       mesh.material = this._Settings.selectMaterial;
+      if (this._Settings.selectByPointCallback)
+      {
+        this._Settings.selectByPointCallback(mesh.id);
+      }
     }
     this.m_bNeedUpdate = true;
   }