code: function (data) {
      var cache = this.cache;
      var cacheCount = this.cacheCount;
      var geometry;
      var hash;
  
      if (data.skipCache) { return; }
  
      hash = this.hash(data);
  
      if (!cache[hash]) { return; }
  
      decrementCacheCount(cacheCount, hash);
  
      // Another entity is still using this geometry. No need to do anything.
      if (cacheCount[hash] > 0) { return; }
  
      // No more entities are using this geometry. Dispose.
      geometry = cache[hash];
      geometry.dispose();
      delete cache[hash];
      delete cacheCount[hash];
    }
docs: Let system know that an entity is no longer using a geometry.