Download CAD/GIS Integration Workgroup - Indiana Geographic Information

IGIC CAD/GIS Integration Workgroup
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Michael Condre, GISP
CAD/GIS Integration Workgroup
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Members:
 Charlene Avey
 Perry Cloyd
 Mike Condre
 Mike Cranfill
 Chelly Gracy
 Nate Hunt
 Steve Leatherman
 Jennifer McMillan
 Eric Meyer
 Tim Smith
 David Surina
 Theresa Thompson
 Jayson Troughton
 Jason Tuck
 Leane Welsh
 Joyce West
 Robert N. Wilkinson
 Phil Worrall

[email protected]
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• The Workgroup is developing a set of
data standards,
 database templates,
 and policy documents

• to support existing best-practices,
integrated with commonly-used software, to
facilitate private industry and local
government data exchange.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• Use of these templates will streamline the
electronic exchange of CAD-based
engineering design data submitted to local
governments for direct integration into a
local government's GIS.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
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Philosophical Assumptions:
 “CAD-to-GIS” means AutoCAD Civil(Map) to ESRI
feature classes most of the time
 We will bring our particular “field” experiences to
bear in recommending attributes
 We will begin from existing standards, where
available
◘ SDSFIE http://www.sdsfie.org/Support/Downloads/tabid/75/Default.aspx
◘ Hag-Tag
 http://www.westfield.in.gov/egov/apps/document/center.egov?path=bro
wse&id=16
 http://www.fishers.in.us/egov/apps/document/center.egov?fDD=160&id=15&path=browse
◘ IU CAD Standards http://www.indiana.edu/~uao/html/cad_gis_standards.html
◘ Others
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• The Workgroup will
publish a summary of all critical layers
necessary to address in the CAD-to-GIS
process,
 provide a schema and specifications for
AutoCAD and ESRI data exchange,
 and examples of existing local government
policy documents to support this effort.

Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup

Coordinate System and Projections
 Data should be created on a known projected
coordinate system along with a known horizontal
datum that align the known coordinate system grids
with the ellipsoids. The recommendation would be
for NAD 83 State Plane, using US Survey Feet units.

MetaData
 “Industry Standard” per philosophical assumptions
◘ AutoCAD Map 3D currently supports two standards for geospatial metadata: the
FGDC CSDGM Standard and ISO 19139.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup

Topological structure
 Objects should be created using a topological
structure such that vertices are snapped and line
segments follow a consistent, logical direction.
 Continuous edges should be represented by
polylines.
 Adjacent features of a common theme generally
should not have gaps or overlaps unless that is their
“true” spatial relationship.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• Topological structure (continued)
 Polygonal areas should be represented by closed
polylines or MPolygon objects.
 Point objects may be points or blocks, but if blocks
are used they should have symmetrically-placed
insertion points so that they may be easily scaled
without losing their “true” coordinate value.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
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Layers, colors, linetypes
 Typically, colors and linetypes should be defined as
“ByLayer” so that these properties may be
adapted as needed by end users for cartographic
communication and specific end uses. Layers should
uniquely discriminate between object classes, and
should be “plain English” descriptions of the object.
We would discourage against using layer names to
carry information that would be better stored as
Object Data tables. Although end users will of
course use additional layer names for specific end
uses, it is understood that this imposes a separate
need for translation to other platforms and uses.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup

Other properties
 Other CAD-based object properties such as explicit
lineweight, linetype scale, etc. are typically used for
cartographic communication purposes and are not a
mandatory part of the Object Classification, however, those
properties can be stored without specifying explicit property
values so that those values may be transferred from CAD to
GIS when useful.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
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Object Data
 Object Data tables as offered in AutoCAD’s
Civil3D product provide a consistent method for
storing and transporting tabular data that is
fairly equivalent to attribute data in GIS,
especially as in ESRI shapefiles and
geodatabase feature classes.
 Object Data can store tabular data on lines,
polylines, and polygons as well as on simple
points and more complex blocks whereas
AutoCAD’s traditional block attributes work on
blocks only. However, block attributes in
conjunction with Link Template definitions are
still a more efficient methodology for linking
CAD objects to external, relational databases
such as Access or SQL.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup

Feature Classes (Object Classes)
 The new process is based primarily on
Object Classes in AutoCAD Map.
From the Autodesk Help Files:
◘ Object classification helps organize and
select objects in your drawings.
◘ Object classification organizes objects in
your drawing based on the real-world
features that they represent, for example,
roads or manholes. When you create an
object using object classification, the object
automatically has properties and values
assigned to it based on its object
classification. In addition, you can find or
select all objects in an object class.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
 Object classification definitions
include
◘ A name assigned to the object
(sanitary_manhole,
street_centerline, etc.)
◘ The entity type of the object (line,
polyline, block symbol, text, etc.)
◘ The graphic properties of the
object (layer, color, linetype, etc.)
◘ The descriptive attributes of the
object (block attributes, Object
Data, or linked database records)
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
 The definitions are stored
in an XML file format,
which also requires a CAD
template file (DWT) to
hold layer and block
definitions. These files can
be used to efficiently and
effectively transfer the
standard both internally
between users and task
sessions, as well as to
external agencies and
vendors for digital
submittals.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• Using Object Classes (formerly known as
“Feature Classes”) in AutoCAD ensures that
there is a data structure on the CAD side
that is very equivalent on the GIS side,
which also uses “feature classes” to
associate and define geographic,
cartographic, and attribute data
properties of both real-world objects and
imaginary ones such as cadastral parcels,
zoning boundaries, etc.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• Having common definitions on each “side” of the
CAD/GIS data structure equation lets us make
“one-for-one” exports, imports, and even roundtripping of data with a minimal amount of pre- or
post-processing time and effort.
• Subject, of course, to typical shapefile limitations
of arc “aliasing” and 8-character field-name
constraints.
Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships
CAD/GIS Integration Workgroup
• Next Steps:
XML generation
 CAD Templates
 Instructional documents / downloadable web
content
 Road Show / publication
 Your Feedback, ongoing improvements and
Success Stories 
 Thanks!

Coordination of Indiana GIS through dissemination of data and data products, education and outreach, adoption of standards, and building partnerships