Save As DWG/DXF Options General tab, Advanced

Used to set advanced options for saving to DWG and DXF files.

Other groups of options under the General tab include:

• Basic

• References

• Line Weights

• Entity Mapping

• Classes

• Cells

• Fonts

• TriForma

Save As DWG/DXF Options General tab, Advanced options

Drop Unsupported LineStyles

If on, drops elements that use custom line styles not supported by AutoCAD to individual components.

Convert Empty Enter-Data Fields to Spaces

If on, converts empty enter data fields within text to space characters (“ “) when the DGN file is saved to DWG. If off, enter data fields are converted to underscore characters (“_”).

Set UCS from Current ACS

If on, sets the AutoCAD UCS (User Coordinate System) from the current ACS (Auxiliary Coordinate System) when the DGN file is saved to DWG. AutoCAD's UCS is similar to MicroStation's ACS, but the UCS is more heavily used in AutoCAD. In particular, AutoCAD always displays coordinate values in the current UCS. This can cause a mismatch with MicroStation, which by default displays world coordinates.

Save Front and Back Clip Planes

If on, sets the front and back clipping planes when a view in a DGN file is saved to DWG. If off, the clipping planes are not defined in the DWG file. In AutoCAD the clipping planes are not widely used and are difficult to control, so the recommended setting is Off.

Save Active Dimension Settings

If on, saves the active dimension settings when the DGN file is saved to DWG. Additional terminator blocks and text styles may also be saved. If off, the dimension settings, associated blocks, and associated text styles are not saved to DWG.

Force Positive Extrusion to Clockwise Arcs

When on, maintains a positive extrusion (and reverses arc direction) when saving clockwise arcs to DWG.

In AutoCAD, arc entities are drawn counterclockwise, while in MicroStation, arcs can be specified in either direction. When saving a clockwise arc to DWG, the direction can be maintained by reversing the extrusion vector. This maintains the arc direction, but the negated extrusion can make the arc difficult to enter within AutoCAD.

DXF Precision (Decimal Places)

Controls the number of decimal places that are saved to DXF files.

The default is 6, but the value can be increased to as high as 16 to create more precise (but larger) DXF files.

Non-Default Design Models

Defines how non-default design models are saved to DWG files. A DGN file can have multiple design models and sheet models. In contrast, a DWG file can have only one design model and multiple sheet models. When a DGN file is saved to DWG, the default design model is saved to model space in the DWG file, and the sheet models are saved to drawing layouts (paper space).

• Create Separate Files
— If selected, each non-default design model is saved to a separate DWG file. The model name is appended to the design file name. Reference attachments to non-default models are saved to XREF inserts pointing to the new separate DWG files.

• Create Paper Space
— If selected, each non-default design model is saved to a drawing layout (paper space) in the DWG model that contains the default design model. Reference attachments are merged according to the Non-Default Models Attachments setting on the References tab.

• Ignore
— If selected, non-default design models are not saved to a DWG file. Reference attachments are merged according to the Non-Default Models Attachments setting on the References tab.

PolyFace Mesh Tolerance Angle

Controls the accuracy of the approximation when elements are saved to polyface mesh entities (see Entity Mapping options).

If curved surfaces or complex shapes with curved boundaries are saved as polyface meshes, then the curved geometry is approximated by the polygonal faces of the mesh. A small angle creates a more accurate representation, but it also increases file size and mesh complexity.

Application Data

Controls whether non-displayable application data is saved to the DWG file. These settings also control whether application data created while editing a DWG file is saved back to the DWG file. MicroStation application data can be attached to individual elements as attribute linkages, or it can be stored as separate Type 66, Level 20 elements. Within a DWG file, data can be attached to entities as extended data (XData) or extended records (XRecords).

Application Data > Save Application Data

If on, saves element attribute linkages to DWG XData, and saves application elements (Type 66, Level 20) to XRecords. When the DWG file is opened in MicroStation, this non-displayable application data is automatically restored to the file. In other words, XData is converted back to the original linkages, and application elements are created from the XRecords.

Since the application data is generally not required or useful in the DWG file, this option is off by default.

Application Data > Save Application Extended Data (XDATA)

If on, preserves XData linkages when the DGN file is saved to DWG.

Applications within MicroStation can define either their own attribute linkage types or create DWG style XData linkages that store data directly into XData format. By default, this option is on, and the XData is available when the DWG file is opened in either AutoCAD or MicroStation.

If the option is off, XData linkages are discarded when saving to DWG.