You can import and export
Microstation DGN version 7 and 8. Bentley Systems, Inc., and MicroStation
programs use the DGN format. Like DWG, a single DGN file can contain
points, lines, areas, text, and other object types.
Importing
Data-element information
is stored in an external database file and linked to graphic objects. AutoCAD Map 3D imports
database link information so you can maintain
the linkage during import.
By default, object colors
are imported to their closest ACI (AutoCAD Color Index)
color. To import object colors using RGB (True Color), edit the mapimport.ini file.
For DGN8, the Input
Layer column lists the model name. To see the layers for
a specific model, you may need to scroll the list.
Driver Options for DGN
7
You can set the following
options when importing DGN 7 files:
| Option |
Description |
| Group Elements By |
Choose Geometry to group incoming
objects by entity type. Choose Level to
group them by their DGN level or level name. Only levels that contain
elements will be imported.
|
| Linkage Extraction |
Allows you to extract MSLinks and FRAMME attribute linkage values
from the DGN 7 file. If you select MSLinks, AutoCAD Map 3D imports up
to three links per object for DGN 7. For each link, two fields are
added to the object data table: mslinks_n, which specifies the key
value, and entity_num_n, which specifies the table. If you select FRAMME,
the following fields are added to the object data table: comp_count,
comp_num, dgnfile, feat_num, state_num, and ufid.
|
| Coordinate Units |
Each DGN 7 file defines a UOR (unit of resolution); in addition,
it can define Sub units and Master units.
Select Master or Sub to
specify which of these units in the DGN 7 file matches the default
unit in the AutoCAD Map 3D map. For example, if the default unit in
your AutoCAD Map 3D map is meters, and meters are the Sub unit
in the imported file, select Sub. If you
select Sub or Master, the UORs in
the DGN 7 file are converted to Sub or Master units
according to the conversion factor in the DGN file header. When you import the file,
one Master or Sub unit
(whichever you choose) will become one drawing unit in your AutoCAD Map 3D map.
The Unit Ratio value indicates the ratio between the Master and Sub units.
For example, if the ratio is 1:12 (as it would be for Feet/Inches),
imported object coordinates will be scaled 12 times bigger if you
select Sub.
NoteWhen you import or
export a DGN file with a master unit of Imperial feet, AutoCAD Map 3D converts
the master unit from feet to meters. In addition, it does not recognize
any subunit selection during the import or export process.
|
| Element Expansion |
Select the options to use during import. For example,
select Explode Complex Strings to
return each component of a complex chain as its own feature (no
feature will be returned for the complex chain as a whole). Otherwise,
all elements of the complex chain merge into a single linear feature,
any arcs in the complex chain become linestrings, and any linkages
on the component elements themselves are lost. Select Propagate
Member Linkages to return the linkages attached to the first component
of the complex chain to supplement any existing linkages. Otherwise,
any linkages on the component elements themselves are lost and only
linkages attached to the complex chain itself are returned.
|
| Cell Expansion |
By default, cells are converted into blocks, maintaining
the cell grouping. You can choose to convert the cells to points instead.
You can also explode the contents of the cells into their component
parts, but the explosion is one level deep only.
|
| Reference Files |
Select Create DWG to read all external
reference files (xrefs) attached to the source data set. If the
reference file has nested references, they are also imported, but
circular references are not. If you select this option, you specify
a location for the folder for these files. If the folder already
exists, you can choose to replace it (overwrite its contents) or
cancel and specify a different location. The default folder location
is the same as the selected DGN file location. If you select Ignore,
reference files are not imported and you cannot change the location
of the folder.
|
Driver Options for DGN
8
You can set the following
options when importing DGN 8 files:
| Option |
Description |
| Group Elements By |
Choose Geometry to group incoming
objects by entity type. Choose Level or Level
Names to group them by their DGN level or level name.
Only levels that contain elements will be imported.
|
| Cell Expansion |
By default, cells are converted into blocks, maintaining
the cell grouping. You can choose to convert the cells to points instead.
You can also explode the contents of the cells into their component
parts, but the explosion is one level deep only.
|
| Coordinate Units |
Each DGN 8 file can define Sub units
and Master units. Specify which
of these units in the DGN 8 file matches the default unit in the AutoCAD Map 3D map.
For example, if the default unit in your AutoCAD Map 3D map is meters, and
meters are the Sub unit in the imported file,
select Sub. When you import the file, one Master or Sub unit
(whichever you choose) will become one drawing unit in your AutoCAD Map 3D map.
The Unit Ratio value indicates
the ratio between the Master and Sub units.
For example, if the ratio is 1:12 (as it would be for Feet/Inches),
imported object coordinates will be scaled 12 times bigger if you
select Sub.
NoteWhen you import or
export a DGN file with a master unit of Imperial feet, AutoCAD Map 3D converts
the master unit from feet to meters. In addition, it does not recognize
any sub-unit selection during the import or export process.
|
| Element Expansion |
Select the options to use during import. For example,
select Explode Complex Strings to
return each component of a complex chain as its own feature (no
feature will be returned for the complex chain as a whole). Otherwise,
all elements of the complex chain merge into a single linear feature,
any arcs in the complex chain become linestrings, and any linkages
on the component elements themselves are lost.
|
| Linkage Extraction |
Allows you to extract MSLinks and FRAMME attribute linkage values
from the DGN 8 file. For each link, two fields are added to the
object data table: mslinks_n, which specifies the key value, and
entity_num_n, which specifies the table. If you select FRAMME, the
following fields are added to the object data table: comp_count,
comp_num, dgnfile, feat_num, state_num, and ufid.
|
| Read Reference Files |
Select Create DWG to read all external
reference files (xrefs) attached to the source data set. If the
reference file has nested references, they are also imported, but
circular references are not. If you select this option, you specify
a location for the folder for these files. If the folder already
exists, you can choose to replace it (overwrite its contents) or
cancel and specify a different location. The default folder location
is the same as the selected DGN file location. If you select Ignore,
reference files are not imported and you cannot change the location
of the folder.
|
