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Object Classification: Best Practices
When setting up and using object classification, follow these guidelines for
the best results:
■ Use only one object class definition (page 313) file for a project. Object classes
should be general enough that a definition for “roads” is appropriate in
any circumstance. Create subclasses for freeways, parkways, small streets,
and so on.
■
Only one person should edit object class definitions at a time, or one set
of edits might be lost. If the definition file was just edited, quit AutoCAD
Map 3D and restart it to get the updated definitions.
■ Distinguish between the Object Type (on the Applies To tab of the Define
Object Classification dialog box) and the Create Method (on the Class
Settings tab). Object Type determines which existing objects you can add
to this
object class (page 313) . If the object was not created with the selected
method, you cannot add it. Create Method determines the method used
to create new objects from this class (when you right-click the object class
and choose Create Classified Object).
NOTE If you plan to use this object class with objects from a drawing source,
do not select more than one object type
■
Avoid renaming object classes, because this changes the name only in the
object class definition file. Objects tagged with the object class name are
unchanged. Since these objects point to a name that no longer exists in
the object class definition file, the objects become undefined. You can
search for undefined objects and update their object class name.
■ Avoid including styling options in object class definitions. For example,
you can draw points using a block. You can specify that block if you use
Block as the Create Method for an object class that represents point data.
However, the block will not scale to the map, and might cause more work
than it saves. Instead, create a drawing layer in Display Manager and assign
the point objects to that layer. Style the layer from Display Manager using
the desired block.
174 | Chapter 4 Tutorial: Classifying Drawing Objects