Dimensions are a special kind of geodatabase annotation for showing specific lengths or distances on a map. A dimension may indicate the length of a side of a building or land parcel, or the distance between two features, such as a fire hydrant and the corner of a building.
A dimension feature is composed of several parts that may or may not be displayed, depending on the application. These parts are each represented differently using different symbology and placement rules. The following is an illustration of the anatomy of a dimension feature:
ArcGIS Pro supports two types of dimensions: aligned dimensions and linear dimensions. Aligned dimensions run parallel to the baseline and represent the true distance between the begin and end dimension points, as shown in the following illustration:
Unlike aligned dimensions, linear dimensions don't represent the true distance between the begin and end dimension points. Linear dimensions can be vertical, horizontal, or rotated, as shown in the following illustration. A vertical dimension's line represents the vertical distance between the begin and end dimension points. A horizontal linear dimension's line represents the horizontal distance between the begin and end dimension points. A rotated linear dimension is a dimension whose line is at some angle to the baseline and whose length represents the length of the dimension line, not the baseline.
All dimensions can be oriented either outward or inward, as shown in the following illustration. Outward dimensions have dimension lines pointing to the outside of the feature and represent the distance being measured between the two boundaries. Inward dimensions have arrows pointing in from the outside of the feature and measure the distance between these two arrows. Whether a dimension is outward or inward is determined by the distance that the dimension represents and whether that distance on the map is sufficient to display all the elements of the dimension between the extension lines.
You can create all these types of dimensions using a number of tools and construction methods available while editing in ArcGIS Pro.
Dimension feature classes
In the geodatabase, dimensions are stored in dimension feature classes. As with other feature classes in the geodatabase, all features in a dimension feature class have a geographic location and attributes and can either be inside or outside a feature dataset. Like annotation features, dimension features are graphic features, and their symbology is stored in the geodatabase.
ArcGIS Pro provides tools that allow you to store dimensions in your geodatabase. You can also create dimension styles to apply to your dimension features so they are consistent with your application standards.
Dimensions are a type of geodatabase annotation. As with regular annotation, the information that dimension features convey is not useful unless you are zoomed in to a scale at which you can visualize the dimension features clearly. When working with dimension feature classes in ArcGIS Pro, you should always apply visual scale ranges so the dimension features only draw at scales at which they can be visualized.