For labels that have a text symbol with a callout, you can use the Maplex Label Engine to set the anchor point for the callout symbol. The anchor point location options where the callout will snap to the feature are as follows:
- Geometric center
If the anchor point is unable to be placed at the geometric center of the polygon, it is placed on the closest point on the outline to the label. The geometric center of the polygon is the center of gravity for the polygon. This center does not always fall within the feature; when it doesn't, the anchor point is placed on the feature outline. This is the default.
- Eroded center
The anchor point is placed at the eroded center of the polygon. The eroded center is determined by stripping away the outer layers of the polygon (like peeling an onion) until there is one center point left. This eroded center always falls within the polygon boundary.
- Closest point on the polygon outline
The anchor point is placed at the closest point on the polygon outline to the label.
- Geometric center of unclipped polygon
The anchor point is placed at the geometric center of the unclipped polygon. If the polygon falls partly outside the current extent, the Maplex Label Engine uses the entire polygon to calculate the geometric center. If the anchor point cannot be placed at the geometric center due to a hole in the feature, the eroded center of the unclipped polygon is used. Because the Maplex Label Engine is using the unclipped polygon to place the anchor point, it may be placed outside the current extent.
The following image shows these callout anchor location options:
- Ensure the Maplex Label Engine is enabled.
- Ensure Labeling is the active way of displaying the Contents pane.
- Choose a label class in the Contents pane and click the Labeling tab.
- On the Labeling tab, in the Label Placement group, click Label Placement Properties .
- In the Labeling pane, click Position and click .
- Expand Leader line anchor points.
- Specify the leader line anchor point type: Geometric center, Eroded center, Closest point on the polygon outline, or Geometric center of unclipped polygon.