Positioning labels with the Standard Label Engine
When you turn on dynamic labeling, the ArcMap Standard Label Engine fits as many labels as possible, without overlap, within the available space on the map. As you pan and zoom, ArcMap automatically adjusts labels to fit the available space. For many maps, the ArcMap default labeling will be adequate. If you need more control over which features are labeled and where labels are placed, you should work with priority, weight, overlap, and placement options. Additionally, if you are labeling line or multipart polygon features, you may want to work with duplicate labels. All these properties work on a label class level.
If further control is needed in placing labels, the Maplex for ArcGIS extension can be used.
As you zoom in and out on your map, the size of your labels will not change. If you want label text size to scale with the map, right-click the data frame and click Reference Scale.
Standard Label Engine placement options
Label placement options control the positioning of labels with respect to features. For example, you might specify that your city labels always be placed above and to the right of the cities.
The Standard Label Engine has different label placement options that depend on the feature type such as point, line, and polygon features.
If you install and enable the Maplex for ArcGIS extension, you will see a different set of label placement options.
Placement options for point features
There are four separate placement options for point features. You can only choose one.
- Offset labels horizontally around the point: Choose this option if you want to place labels around the points, but not on top of them. You can pick a placement pattern that ensures that a given label is only placed in one location with respect to the feature, for example, above and to the right. Or you can pick a pattern that prioritizes several placement options. For example, ArcMap will first try to place a label above and to the right of the feature. Then, if it can't fit the label, it will try the bottom and to the right.
- Place label on top of the point: Choose this option to center the label on top of the point.
- Place label at specified angles: Choose this option to enter a list of proposed angles for your labels. ArcMap will try to place all labels using this list. As ArcMap labels each feature, the first angle in the list will be tried first. If there's a conflict, subsequent angles in the list will be tried until the label is placed successfully.
- Place label at an angle specified by a field: Choose this option if you have an attribute in your layer that specifies the angle to rotate each label. This option gives you control over label angles on a feature-by-feature basis. Angles should be specified in degrees.
Placement options for line features
There are three categories of settings under placement options for line labels. Unlike point labels, all these settings work together to determine label placement.
- Settings that control label orientation: The default line label orientation setting is Parallel, meaning straight and placed at an angle that follows the line. You can also place labels perpendicular to the line (rotated 90 degrees from parallel). The Horizontal option is primarily used when labeling road features with highway shields. This option places labels horizontally on the page.
To place labels that follow the curve of the lines being labeled, choose the Curved option.
- Settings that control the position of labels with respect to the side of line features: Choose an orientation system to use when constraining the placement of labels to a particular side of your line features. If you choose page orientation, you can constrain your labels to any of the following positions: Above, On the line, or Below. You can choose more than one.
If you choose line orientation, you can constrain your labels to any of the following positions: Left, On the line, or Right. Again, you can pick more than one. If you choose to place labels on either side of the line (not on the line), you can also specify a perpendicular offset distance for each label from the line.
- Settings that control label location along each line: You can specify whether you want labels to be placed at the start, end, or best position along the line. At Best is the default setting.
Label placement options for polygon features
There are three separate label placement options for polygon features. By default, labels are placed always horizontal at the center of each feature.
- Always horizontal: Labels are placed horizontally at the center of each feature.
- Always straight: Each label will be placed so that it follows the longest direction of the polygon being labeled.
- Try horizontal first, then straight: The first attempt will be to place the label horizontally, and if this is not possible, straight placement will be attempted.
You can also choose whether to place each label only if it falls completely inside the polygon feature being labeled.
When labeling line and polygon layers, you can choose one of the following three options for handling duplicate labels. There are no duplicate label options when labeling point features.
- Remove duplicate labels: This is the default when labeling line features. When two or more contiguous features have the same label text string, only one label will be placed. This prevents seeing potentially many of the same labels on your map.
- Place one label per feature: A label will be placed for every feature. Duplicate labels will not be removed.
- Place one label per feature part: A label will be placed for each part of a multipart feature. Duplicates will not be removed.
If you install and enable the Maplex for ArcGIS extension, you will see different options for working with duplicate labels.