docs: protected void onDrawFrame() {
  
          int numActiveMeshes = meshInfo.size();
          for (int i = 0; i < numActiveMeshes; i++)
          {
              float currMeshSpawnTime = meshInfo.get(i).second;
              if (currTime - currMeshSpawnTime > mMaxAge + 1) {
                  GVRSceneObject toDelete = meshInfo.get(i).first;
                  GVREmitter.this.removeChildObject(toDelete);
                  idxsToDelete.add(i);
              }
          }
          for( int i = idxsToDelete.size() - 1; i >=0; i -- ) {
              meshInfo.remove((int)idxsToDelete.get(i));
          }
  
          idxsToDelete.clear();
      }