code: function (data) {
      var cache = this.cache;
      var cachedGeometry;
      var hash;
  
      // Skip all caching logic.
      if (data.skipCache) { return createGeometry(data); }
  
      // Try to retrieve from cache first.
      hash = this.hash(data);
      cachedGeometry = cache[hash];
      incrementCacheCount(this.cacheCount, hash);
  
      if (cachedGeometry) { return cachedGeometry; }
  
      // Create geometry.
      cachedGeometry = createGeometry(data);
  
      // Cache and return geometry.
      cache[hash] = cachedGeometry;
      return cachedGeometry;
    }
docs: Attempt to retrieve from cache.
  
  @returns {Object|null} A geometry if it exists, else null.