About Working with Multiple Coordinate Systems

In an enterprise industry model , a project can contain several industry models , and each one can have a different coordinate system (SRID). In an enterprise industry model, the SRID is used for on-the-fly coordinate transformation to represent the geometry data in AutoCAD Map 3D in a single global coordinate system. Any data you edited is converted back to its original coordinate system when you save it back to its source.

Areas affected by coordinate transformation

• Generating graphics
• Editing data in the drawing, for example, digitizing features, modifying features, and creating features from geometry
• Viewport definition in the drawing. For example, if you specify a viewport by dragging a rectangle in the drawing, a transformation is performed. However if you define a viewport by typing the coordinate values, you must use the industry model coordinates.

Note:

All calculations are made in the industry model coordinate system. Coordinate values shown in dialog boxes and feature class forms are the internal database values.

Displaying a Map with Coordinate Transformation

When you generate your map, AutoCAD Map 3D checks the configuration of the coordinate systems and performs transformations if necessary.

Sample cases

• The AutoCAD Map 3D drawing has an assigned global coordinate system. The coordinates of the industry models are transformed into this system for representation in the map.
• The AutoCAD Map 3D drawing has no global coordinate system assigned. The industry model has an SRID assigned. The enterprise industry model sets the global coordinate system to the industry model SRID.
• The AutoCAD Map 3D drawing has no global coordinate system assigned. At least one of the industry models in the current project has an SRID assigned. No transformation can be performed.
• The AutoCAD Map 3D drawing has a global coordinate system assigned. The industry model (or one of the industry models in the project) has no SRID. No transformation can be performed. A message informs you about this: A coordinate system has been globally assigned, but not for the following industry model:.

Note:

If theAutoCAD Map 3D drawing has a global coordinate system assigned, all industry models in the current project must have an SRID. In Infrastructure Administrator, you can update the SRID of existing industry models.

All feature classes of an industry model have the same coordinate system. The layer coordinate systems must not be modified in the FDO data connection properties. Any modifications you made will be reset to their default values before graphic generation.