Extensions > Maplex > Getting started with Maplex
An overview of labels and annotation |
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Release 9.1
Last modified April 26, 2005 |
Print all topics in : "Getting started with Maplex" |
- Using text formatting tags for labeling
- Better labeling with label classes and label expressions
- Using the map cache to improve geodatabase labeling performance
- Labeling features of a layer
- Labeling features of a layer using label classes
- Creating label classes based on symbology classification
- Creating label expressions
Labels are dynamically generated in ArcMap. The labels for a feature class are created using feature attributes from a layer in a map. A feature label can be saved using a variety of parameters with a layer to adjust the label's appearance. As you pan and zoom around your map, ArcMap adjusts the labels to best fit the available space. At smaller scales, you may see fewer labels because ArcMap has less empty space in which to place them. Because not all features can always be labeled, you might want to prioritize the labeling of some features. For instance, on a map of Europe, you may want ArcMap to label a country with its name instead of labeling a city if both labels won’t fit.
You can set the labeling priority for each layer on the map. When there are label placement conflicts, a feature in a layer with a higher priority will be labeled before a feature in a layer with a lower priority. Similarly, within a single layer, you can set labeling priorities on specific groups of features—for example, you might set a high labeling priority on cities with larger populations and a low priority on cities with smaller populations. Groups of features within a layer are represented by label classes.
Labels are most useful for interactive maps, where the scale and extent varies with use, and where it is not critical that any given label be placed in a particular spot. When you use such labels, there is no guarantee that you’ll get exactly the labels you want, positioned exactly where you want them. When you need precise control over the placement of labels, such as when you are creating a map for publication, you must manage the labeling process more closely.
Maplex for ArcGIS is useful for creating high-quality, dynamic labels for everyday use and for maximizing the number and quality of labels placed on a map. If you need even more control of the placement of labels on a map, you may choose to refine the positioning of labels with Maplex for ArcGIS and convert the labels to annotation.
Learn more about labeling in ArcMap
When you need to be able to specify exactly where descriptive text will appear on a map, you can convert the labels to annotation. Converting labels to annotation allows you to manually adjust the label for each feature. Annotation differs from labels in that annotation is text that is stored at a specific geographic location. After you’ve converted labels to annotation, you can work with each piece of annotation independently—to move it, change its size or font, or change the text. For example, you might want to move a few pieces of annotation to make room for one that ArcMap was unable to place. ArcMap also provides you with a list of all the labels that weren't placed during the conversion process and lets you interactively place them on your map as needed.
While annotation is typically text, it can also be any graphic element that annotates your map—such as lines, circles, and polygons.
Another reason to convert labels to annotation is to enable you to share the high-quality labels generated by Maplex for ArcGIS with someone who has ArcReader or someone who has ArcMap, but not the Maplex for ArcGIS extension.
Once you’ve decided to convert labels to annotation, you have a choice of where to store the annotation. You can store annotation in the map document in an annotation group, or you can store annotation in a geodatabase as an annotation feature class and reference it like other data on your map.
Storing annotation in a geodatabase is similar to storing geographic features—line, point, and polygon—in a geodatabase. You can add annotation stored in a geodatabase to any map, and it will appear as a layer in the map’s table of contents. A given annotation feature class can have subtypes that store different sorts of annotation, somewhat like the different label classes that can be associated with a given feature layer.
Where should you store annotation?
Where you store annotation depends on how you plan to use the annotation. Use the following guidelines when making your decision:
- If you’re creating a map specifically for printing, and the annotation you’ve created applies only to this map, store the annotation in an annotation group in the map document. Then, if you delete the map, the annotation is also deleted because it’s stored in the map.
- If you want to use the annotation on other maps—because you’ve invested time and effort to position them—store them as an annotation feature class in a geodatabase. You can add the annotation as a layer to other maps.
- If you intend to use the map to interactively browse your data, and that map has numerous labels—as a general rule, more than 100—store them as an annotation feature class in a geodatabase for better drawing performance. ArcMap can access and display an annotation feature class more rapidly than annotation in an annotation group in the map document.
You can also link annotation in a geodatabase directly to the feature it annotates, creating feature-linked annotation. Then, if you move the feature, the annotation moves with it; if you delete the feature, the annotation is also deleted; and if you change the attribute of the feature on which the annotation is based, the text of the annotation changes.
You create feature-linked annotation for a specific feature class—rather than the entire map—and store it in the geodatabase along with the feature class it’s associated with. You’ll typically create feature-linked annotation while editing your geographic data with the Editor. However, you can also convert labels into feature-linked annotation.
Learn more about working with feature-linked annotation
Learn more about converting labels to annotation