Dimensions can be associative, which mean that they adjust to changes in the geometric objects that they measure.
Dimension associativity defines the relationship between geometric objects and the dimensions that give their distance and angles. Several types of relationships are possible between geometric objects and dimensions. Leader and multileader objects can also be associative.
- Associative dimensions automatically adjust their locations, orientations, and measurement values when the geometric objects associated with them are modified. Dimensions in a layout may be associated to objects in model space. These are created when the DIMASSOC system variable is set to 2.
- Partially associative dimensions exist when only one extension line is associated with a geometric object. This typically occurs when a geometric object associated with a dimension is deleted.
- Non-associative dimensions can be selected and modified with the geometry they measure, but they do not change automatically when the geometric objects they measure are modified. These are created when the DIMASSOC system variable is set to 1.
- Exploded dimensions contain a collection of separate geometric and text objects rather than a single dimension object. These are created when the DIMASSOC system variable is set to 0, or when you apply the EXPLODE command to an existing dimension.
You can determine whether a dimension is associative or non-associative with the Properties palette or the LIST command. You can use the DIMREASSOCIATE command to reassociate partially associative or non-associative dimensions.
Tip: You can use DIMREGEN to update associative dimensions after panning or zooming model space in a layout viewport, after opening a drawing that was modified with an earlier release, or after opening a drawing with external references that have been modified.
The Annotation Monitor
You can track annotations that lose associativity with the help of the annotation monitor. Associativity can be lost for several reasons:
- Associativity is not maintained if an associated geometric object is modified significantly or deleted.
- Associativity is not maintained if an associated block is redefined such that the edge that the dimension is associated with is displaced.
When the annotation monitor is turned on, it identifies the annotations that have lost associativity by displaying a badge. In the example, when the circle is erased, the dimension associativity is lost and a badge displays on the affected dimension.
Clicking the badge, displays a menu with options that are specific to the disassociated annotation. In this example, the menu provides access to the DIMREASSOCIATE and ERASE commands.
Special Situations and Limitations
Associative dimensions support most types of geometric objects that you would expect to dimension. They do not support objects such as
- Hatches
- Images
- Underlays
- Multiline objects
- 2D solids
Note: Dimensions associated to model drawing views may lose their associativity if the drawing is opened and re-saved in a pre-2012 release of AutoCAD.