Use the Patterns tab of the Modify DGN Export Setup dialog to map Revit fill patterns to hatch patterns in DGN.
By default, each Revit fill pattern listed in the mapping table has a corresponding DGN hatch pattern generated automatically upon export. This hatch pattern matches the Revit fill pattern.
To map a fill pattern to a specific DGN pattern, do the following:
To change all the values in the table back to {Automatically generate pattern}, click Reset All.
At the bottom of the tab, under Pattern Type, specify the type of fill patterns (drafting or model) to list in the table. The available pattern options are the same, regardless of the pattern type selected.