Update app.py

app.py

@@ -604,11 +604,17 @@ async(c, o, b, p, d, n, m)=>{
         document.getElementById("model3D").getElementsByTagName("canvas")[0].oncontextmenu = function(e){e.preventDefault();}
         document.getElementById("model3D").getElementsByTagName("canvas")[0].ondrag = function(e){e.preventDefault();}
 
-        if (o.indexOf(n) < 0) {
+        if (o.indexOf(""+n) < 0) {
           if (o != "") { o += ","; }
           o += n;
         }
+        alert(o);
         var o_ = o.split(",");
+        var q = BABYLON.Engine.LastCreatedScene.meshes;
+        for(i = 0; i < q.length; i++) {
+          let mesh = q[i];
+          mesh.dispose(false, true);
+        }
         var dome = [];
         for (var j=0; j<o_.length; j++) {
           o_[j] = parseInt(o_[j]);