Available for an ArcGIS organization licensed with the Indoors extension.
Part of preparing Autodesk AutoCAD floor plan drawings for the ArcGIS Indoors Information Model includes aligning to certain quality standards before import.
The guidance on the AutoCAD quality standards below helps ensure that the data is ready for the Indoors model, and the listed best practices help ensure successful import.
CAD drawing requirements
The following data preparation requirements ensure that AutoCAD data can be used in ArcGIS without issue.
Coordinate systems
All drawings must be properly positioned to ensure that the building and floor plan features are in the right place at the right size for the corresponding coordinate system. The data must be drawn to scale and the drawing units must match the georeferenced units in ArcGIS.
You can georeference AutoCAD drawings in AutoCAD Map 3D or in ArcGIS Pro. This must be completed before importing the AutoCAD floor plans into the Indoors model using the Import Floorplans To Indoors Geodatabase tool.
Layer content
The AutoCAD layers you want to use in the Indoors model must be turned on and unfrozen. Ensure that the layers for important geometries such as levels, units, and facilities are included.
Tip:
When importing AutoCAD floor plans into ArcGIS Pro, you can create facility boundaries by merging level footprints.
Topologically clean data
Review the drawing files thoroughly to ensure that the geometries do not contain any of the following:
- Undershoots—AutoCAD lines that are mapped to the Indoors model polygon feature classes must close. Undershoots prevent the creation of correct Indoors polygons.
- Self-intersections (features overlap a segment of themselves)—This can cause the feature import to fail.
- Duplicate objects—Objects in the same layer that represent the same feature create duplicates in the Indoors model.
Tip:
AutoCAD Map 3D includes a Drawing Cleanup tool that fixes some of the items listed above. In AutoCAD, there are also Purge, Overkill, and Audit tools that can help you manage these conditions, and you can also configure the constraint settings for the Auto Constrain tool to detect these items.
In ArcGIS Pro, the Repair Geometry tool also addresses some of the items listed.
Proxy objects and external references
Remove proxy objects from the drawing file because they don’t import into Indoors as intended. They are often used for logos or complex point-of-interest symbols, but after import into Indoors, the resulting feature may not have any meaning without the content it represents.
Referenced drawings (xrefs) that are inserted using the Bind option in AutoCAD are supported. Xrefs created without using this option do not appear in Indoors. However, you can configure one or more CAD drawings in the Source Files sheet for Indoors to import the AutoCAD data properly.
Annotation layers
Layers containing identifying text (annotation) are required to identify indoor spaces, such as conference room names or restroom labels. Include annotation to indicate space use types, such as Office or Stairway, to allow symbolizing units by use type in indoor maps.
Ensure that each annotation’s insertion point is positioned within the associated space. ArcGIS uses the insertion point to verify the annotation location. For example, if a room label’s insertion point is not within that room, the label does not appear as expected in Indoors.
Place drawing metadata—such as titles, borders, and other textual attributes such as the architect’s information—into a separate layer from the layers that contain geometries to prevent AutoCAD drawing metadata from appearing in the Indoors results.
Best practices
The recommendations below ensure that AutoCAD data appears as expected in the Indoors model.
Layer content
Set layer properties to ByLayer to make it easier to identify objects in the AutoCAD drawing and populate the configuration spreadsheet file.
Ensure that none of the layers you include in the spreadsheet are empty. Empty layers can cause confusion if there is content that is expected to be in a layer.
The use of blocks versus individual objects should be consistent. A mix of the two may require you to perform the import process multiple times to ensure that all intended objects are brought into Indoors.
If you plan to create networks for indoor navigation, include layers that represent openings as well as any kind of obstructions, including walls.
Topologically clean data
Review the drawing files thoroughly to ensure that the geometries do not contain any of the following:
- Overshoots.
- Zero-length polylines (lines that have the start and end vertex in the same place).
- Overlapping objects in the same layer that represent units, facilities, levels, sections, or zones.
- Snapping on edges—Snapping must be made on vertices.
- Islands, holes—Identify islands and holes in the AutoCAD drawing to verify after you have imported the data into ArcGIS. In some cases, you may need to clip the island or hole out of the surrounding polygon feature to obtain the correct topology.
- Objects that cross each other and have no node at the crossing.
Tip:
AutoCAD Map 3D software includes a Drawing Cleanup tool that fixes some of the items listed above. In AutoCAD, there are also Purge, Overkill, and Audit tools that can help you manage these conditions. You can also configure the constraint settings for the Auto Constrain tool to detect these items.
In ArcGIS Pro, the Repair Geometry tool also addresses some of the items listed.
Use closed polylines for Facility, Level, and Unit polygon features. The Import Floorplans To Indoors Geodatabase tool can also generate polygon features from a combination of unclosed lines (such as walls, windows, and doors), but with an increased chance of topology or other issues.
Draw lines and closed polylines as lightweight polylines (LWPOLYLINE). LWPOLYLINE closes on itself most consistently in AutoCAD and works well in Indoors.
The following geometry types cause complications in Indoors and may not adhere to snapping or coincident options:
- Ellipses
- Splines
- Arcs
For example, an arc is depicted in Indoors as a starting vertex and an ending vertex. The radius center point, however, does not properly display.
If arcs or ellipses were used, convert them to polylines.
Annotation
A recommended practice for the placement of title attribute blocks is to insert them at a lower left coordinate of the drawing. This attribute title block usually contains information that helps identify project and drawing details.
The annotation layer used to create the UNIT_ID field should contain a unique value for each unit. The following common issues can occur:
- Multiple units contain the same annotation—If multiple features on the same level have the same annotation value (for example, two stairways named Stairway in the annotation layer), they are assigned identical values for the UNIT_ID field when you import floor plans to the indoor dataset. If you update floor plans and load them to the same indoor dataset, the duplicate feature is removed.
- Some units are missing annotation—If annotation is not included for a unit feature, it is assigned a sequential number as an identifier. If units are added or removed to the floor plan, the same feature may be assigned a different number when you import your updated floor plans to the indoor dataset. When this occurs, units are imported as new features.
You can map this annotation layer to the UNIT_ID field in the CAD floor plan template file before using the Import Floorplans To Indoors Geodatabase tool.