About Importing ACIS Objects

ACIS^® objects describe solids or trimmed surfaces. Revit supports the import of ACIS objects contained in DWG, DXF, DGN, and SAT files.

ACIS objects from SAT files

You can import ACIS objects using SAT files, a 3D modeling technology by Dassault Systèmes, Spatial Corporation.

This functionality leverages sophisticated technology to provide more consistent and higher quality 3D imports than other import technologies. When imported into projects and families, these 3D shapes adopt some of the behavior of the assigned Revit categories. As a result, the 3D shapes provide greater intelligence in the model than other types of imported geometry.

To import ACIS objects from SAT files, use the procedure Import a 3D Shape. See also About Importing 3D Shapes.

Note: Revit imports ACIS^® solids from SAT^® files. SAT file formats later than version 7.0 do not import into Revit. Determine which version your solid modeling program creates. Some solid modeling products (such as form-Z^®) create SAT file formats later than version 7.0 by default.

ACIS objects from DWG, DXF, and DGN files

You can create ACIS objects using the AutoCAD commands Draw Solids and Draw Region. You can also import SmartSolids™ from MicroStation^® into Revit.

To import ACIS objects from DWG, DXF, and DGN files, use the procedure Import a CAD File.

Revit supports the following types of surfaces when importing ACIS objects using these file types:

• Plane
• Sphere
• Torus
• Cylinder
• Cone
• Elliptical cylinder
• Elliptical cone
• Extruded surface
• Revolved surface
• NURB surfaces

You can import NURB (non-uniform rational B-splines) surfaces on ACIS objects in DWG or SAT files into mass or generic model families while you are creating the family.

You can then use the Roof by Face and Curtain System by Face tools to create roofs and curtain systems on these imported surfaces.

To use ACIS imports for face-based host tools, import geometry into an in-place family of category Mass or Generic Model. Face-based tools work best on ACIS solids.

For example, if you create walls by face on a cube, the walls join and miter correctly. If you create a curtain system by face on a solid, you can add corner mullions onto the joins between faces of the curtain system. For more information on face-based tools, see Creating Building Elements from Mass Instances.

Tip: Make sure you import the geometric data needed for the Revit capability that you plan to use. For more information, see About Imported Geometry.