DXF/DWG and DWF File Formats

Units

Version 2000 DXF/DWG and later supports the concept of units, so the file’s unit settings can be imported (if it includes units). Previous versions of DXF/DWG do not support units, and some version 2000 and later files may be unitless. There is no way for the Vectorworks program to tell whether these unitless drawings were made in meters, feet and inches, or microns. Communicate with the person providing the file to determine this information. Unitless DXF/DWG files do have five “units” settings (such as “Architectural” and “Engineering”) which are used to guess the original units, but the guess may need to be adjusted.

Line Weights

The Vectorworks program allows line weights and colors to be specified independently. AutoCAD has gained the ability to do so, but most AutoCAD users still use colors to map to line weights. Version 14 and earlier DXF/DWG files do not support true line weights at all. If you choose to export with line weights mapped to colors, then original object colors will be lost.

Colors and Fills

The Vectorworks program is more graphically rich than DXF/DWG can currently support. In all cases, the Vectorworks program chooses the closest possible translation given the limitations inherent in DXF/DWG. The default version in the export dialog box will always give the best results possible, assuming the recipient’s software can read all of the information.

DXF/DWG versions prior to 2004 have a fixed color palette (which changes slightly depending on whether the background is black or white) and all objects have just one solid color associated with them. Objects such as circles in DXF have no fill color (just a line color). A few objects can have a fill color, but they have no separate line color.

DXF/DWG version 14 and above supports a “solid hatch,” which is a separate object that can be associated with objects such as circles to make them look like they have a color fill. These hatches cannot be the same color as the background color (such as a white rectangle on a white background to mask objects underneath). Since these solid hatches can be associative, the Vectorworks program can import them and set the associated object’s fill color instead of having two separate objects for frame and fill.

DXF/DWG version 2000 supports “wipeout” entities, which are essentially polygonal images filled with the background color. Some AutoCAD users may not want to receive files with wipeouts. DXF/DWG export includes an option to exclude solid fills (which includes both wipeouts and solid hatches). Since wipeouts can only be polygons and are not associative, if a white circle on a white background is exported and then re-imported into a Vectorworks file, the result is an unfilled circle and a polygon with a white fill and no pen inside the circle. The smoothness of the polygon (number of facets) depends on the 2D conversion resolution preference when it was exported.

Objects with pattern fills export as a plain solid color.

Surface hatches associated with a Renderworks texture must be exported as standard AutoCAD hatches.

Layers and Classes

Each Vectorworks design layer is similar to a DXF/DWG model space. A Vectorworks drawing can have many design layers visible at the same time, with different scales and views for each design layer, but only one model space is allowed in a DXF/DWG file. Therefore, the Vectorworks program has to merge the multiple design layers, and some information can be lost. The drawing should generally look and print the same after the export, but independent layer scales, object coordinates, and invisible objects can be lost.

Groups and Symbols

The Vectorworks program uses symbols, which are objects that can be inserted multiple times without greatly increasing the file size, and which need only one edit to update all copies. It also has groups, which are objects that are grouped together and act as one object. The DXF/DWG equivalent of a Vectorworks symbol is called a “block.” The closest DXF/DWG equivalent to a Vectorworks group is an “anonymous block,” which is like a symbol without a name. Unlike anonymous blocks, named blocks can be edited easily in AutoCAD, and new instances of the blocks can be inserted into the drawing. However, named blocks re-import into Vectorworks files as symbols, which may not be desirable. Therefore, the Vectorworks program has an option to export groups as anonymous blocks, if named blocks cause a problem.

Attributes and Linked Text

DXF/DWG does not have database records that correspond to Vectorworks record formats. It does have objects called attribute definitions (“attdefs”) which, when placed in blocks/symbols, behave somewhat like linked text in a Vectorworks file. The correspondence is very loose and as a result, translation of these objects is not always smooth. DXF/DWG block attributes are created for things exporting as blocks (symbols, groups, plug-in objects, or layer links) that have record formats attached. Because only DXF/DWG blocks can have attributes attached, the record format information is not exported for other object types, such as lines or circles.

Names

When exporting to DXF/DWG version 2000 and later, the characters in layer and block names will not change. Accurate translation of lower case text, spaces and other Unicode characters is supported (except for the following illegal characters, which are converted during export: < > " `, / \ : ? * | = ). Export to previous versions converts all name characters to uppercase; all spaces and special characters are converted to underscores. DXF/DWG attribute tag names cannot have spaces in any version; any spaces found in record field names are converted to an underscore.

Styled Multiline text

Multiline formatted text includes various sized fonts that are bold, underlined, or italicized, and that wrap to the next line. This type of text is supported for DXF/DWG versions 13 and up. For earlier versions, wrapped text is split into separate lines.

Layer Transfer Mode / Transparency

DXF/DWG does not support layer transfer modes or transparency, so use only paint transfer mode (100 percent opaque on Mac systems and on Windows systems that have GDI+ imaging enabled)

Dimensions

The Vectorworks and AutoCAD programs handle dimensions, units, and dimension standards very differently. The Vectorworks program also creates appropriate dimension styles for all dimension standards that are used in the file, so even if the recipient modifies the dimensions or creates new ones, they should not look significantly different. During import, the dimension styles from the DXF/DWG file will be created as custom dimension standards in the Vectorworks file, to preserve the original look.