Patterning and Hatching

MicroStation patterning is similar to AutoCAD hatching.

Working with Patterning and Hatching in DWG Workmode

In DWG workmode, MicroStation patterning is replaced by AutoCAD hatching.

The Pattern field in the Pattern Area tool settings window, by default, lists the patterns in the DWG pattern file areapat.pat. This file contains a DWG pattern definition for each pattern cell in the supplied cell library, areapat.cel.

To select a different DWG pattern file, key in its full file specification — path and filename — in Pattern File or click the adjacent browse icon to browse the file system.

A corresponding DWG pattern file is supplied for each of the supplied pattern cell libraries, such as archpat.cel, areapat.cel, geompa.cel, igespats.cel, linepa.cell, and utilpat.cel. These DWG pattern files have the same filename as their cell library counterparts, except their extension is .pat.

To select a different DWG pattern file, key in its full file specification — path and filename — in Pattern File or click the adjacent browse icon to browse the file system.

When a pattern uses a line style that is not solid, saving as DWG will drop it to an anonymous block with a name prefix "*X".

MicroStation can control the display of filled elements and patterns separately in the View Attributes dialog, but AutoCAD has only one system variable FILLMODE that controls both the parameters. When FILLMODE is turned on, both filled and hatch areas are displayed in AutoCAD. When FILLMODE is turned off, neither is displayed. For DWG compatibility, Fill and Patterns should be set to the same state - both on or both off in the View Attributes dialog. However, if you have a DGN file that has Fill and Patterns set differently, and if you save your DGN file as DWG, you should expect the following cases:

Fill on and Patterns off:
- Select a valid view for Source of Level Display in the Save As DWG/DXF Options dialog.
- Patterns in active file will not be saved in the DWG file, retaining the display of patterns turned off.
- Patterns in reference files will be saved regardless of the View Attributes of master file, but FILLMODE will be set based on reference file's Fill/Patterns state in the output DWG reference file.
Fill off and Patterns on:
- Select a valid view for Source of Level Display in the Save As DWG/DXF Options dialog.
- Patterns will be saved in both active and reference files.
- FILLMODE will be turned on in the output active DWG file (that is, you will see Fill turned on when you open the saved DWG file).