You can increase the number of labels placed in areas where there are label or feature conflicts by allowing the font size and width to be reduced using the Maplex Label Engine. You can reduce the font size from the labels' base font size to a minimum font size using steps of a given size. You can also reduce the length of a label by compressing it horizontally to a given percentage of its original length in discrete steps. These techniques can be applied together so the font width compression steps are tried for each of the font size steps.
The font size and width are not compressed or reduced if the label expression contains text formatting tags that specify the label's font size or line leading.
Reduce the font size
Reducing the font size reduces the overall size of labels in areas where there are conflicts. When you allow the Maplex Label Engine to reduce the font size, you can set a lower limit on the font size and define a step interval that instructs the font size variants for the label engine to try between the font's original size and the lower limit.
- Font size reduction Lower limit is the smallest allowable reduced font size. This parameter instructs the Maplex Label Engine to reduce both the font height and width without changing the aspect ratio.
- Font size reduction Step interval is the amount by which the font size may be progressively reduced to place a label.
For example, for a label with a base font size of 10 points, you can set a lower limit of 6 points and a step interval of 0.5. The Maplex Label Engine places variants of the label using 10, 9.5, 9.0, or 8.5 points, starting at the base font size and reducing it by the step interval until the lower limit is reached. Once the label is placed, the smaller size levels are not tried.
The image below shows font size reduction being used to fit the Whispering Pines Lane label into the street feature. If font size reduction was not used, the label would not be placed on the map.
Compress the font width
Compressing the width of the font for a label reduces the length of the label but not its height. As with font size reduction, you control how much the label is reduced by setting a minimum and a step interval. However, for font width compression, these limits are specified in terms of a percentage of the base font width of the label. The lower limit can range between 0.1 and 100 percent of the original font width, and the step interval can range between 0.1 and 50 percent of the base font width.
- Font width compression Lower limit is the smallest allowable font compression ratio.
- Font width compression Step interval is the amount by which the font width may be progressively compressed.
For example, you can allow the label engine to compress the width of the font in a label to 85 percent of its original width and use a step interval of 5 percent. The label engine places the label at 100 percent of its original width. If it didn't fit, the label engine compresses to 95 percent, 90 percent, and 85 percent, stopping when the label fits. Once the label is placed at a certain compression level, the lower levels are not tried.
The image below shows font width compression being used to fit the Whispering Pines Lane label into the street feature. If font width compression was not used, the label would not be placed on the map.
Reduce and compress labels
You can use font size reduction and font width compression together to increase the number of labels that are placed. The Maplex Label Engine will try font compression and font reduction combinations in an order matching the Strategy order.
For example, if the base font size for a label is 10 points, and you set the lower font size limit to 8 points and a font size step interval of 0.5 points, there are five font size possibilities. If you also set the font compression lower limit to 85 percent and the compression step interval to 5 percent, there are four font compression levels. The Maplex Label Engine tries the resulting 20 size and width combinations in the following order when the Font compression strategy is higher than the Font reduction strategy:
- Font size of 10 pt, 100 percent font width
- Font size of 10 pt, 95 percent font width
- Font size of 10 pt, 90 percent font width
- Font size of 10 pt, 85 percent font width
- Font size of 9.5 pt, 100 percent font width
- Font size of 9.5 pt, 95 percent font width
- Font size of 8 pt, 100 percent font width
- Font size of 8 pt, 95 percent font width
- Font size of 8 pt, 90 percent font width
- Font size of 8 pt, 85 percent font width
Be aware of the proportion of the initial font size, lower limit, and step interval values. More trial sizes mean more processing time.
- Ensure that the Maplex Label Engine is enabled.
- Ensure that List By Labeling is the active method of displaying the Contents pane. Click the List By Labeling tab .
- 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 the Fitting strategy tab .
- Expand Reduce size.
- Check the Reduce font size check box.
If scale-based label sizing is enabled, the initial font size listed is a range of values. The reduction starts from the font size for the active scale.
- Specify Lower limits and Step intervals for your selected font size reduction types.