code: function setCoverage( coverage, level, x, y, covers ) {
      if ( !coverage[ level ] ) {
          $.console.warn(
              "Setting coverage for a tile before its level's coverage has been reset: %s",
              level
          );
          return;
      }
  
      if ( !coverage[ level ][ x ] ) {
          coverage[ level ][ x ] = {};
      }
  
      coverage[ level ][ x ][ y ] = covers;
  }
docs: @private
  @inner
  Sets whether the given tile provides coverage or not.
  
  @param {Object} coverage - A '3d' dictionary [level][x][y] --> Boolean.
  @param {Number} level - The resolution level of the tile.
  @param {Number} x - The X position of the tile.
  @param {Number} y - The Y position of the tile.
  @param {Boolean} covers - Whether the tile provides coverage.