code: function(chains) {
      var vertArrays = this.vertArrays();
      var selectedArrays = [];
      var set = {};
      for (var ci = 0; ci < chains.length; ++ci) {
        set[chains[ci]] = true;
      }
      for (var i = 0; i < vertArrays.length; ++i) {
        if (set[vertArrays[i].chain()] === true) {
          selectedArrays.push(vertArrays[i]);
        }
      }
      return selectedArrays;
    }
docs: returns all vertex arrays that contain geometry for one of the specified chain names. Typically, there will only be one array for a given chain, but for larger chains with mesh geometries a single chain may be split across multiple vertex arrays.