Placement of Dynamic Labelling

Dynamic labelling refers to a method of placing labels on maps where the characteristics and placement of the labels are dynamically adapted based on user interactions and the context of the map. This approach allows for the creation of labels that respond to changes in zooming, panning, and other user interactions, ensuring clarity and legibility. Dynamic labels are generated in real-time using labelling expressions stored with the data, allowing for flexible and automated label placement.

Within the visible map area, the position and size of labels will continuously and rapidly adjust in real-time in response to user interactions such as zooming and panning. To optimize the effectiveness of these adjustments, it is important to follow certain best practices. Although there are no hard guidelines for label configuration, it is recommended to adopt the following rules:

Labels for point feature are typically placed horizontally and can be tightly positioned around the point in various locations.

Labels for line features are typically aligned with the direction of the line and centered on it. However, in practical scenarios where line features are densely distributed and highly curved, different algorithms are employed to achieve visual harmony.

Determining the placement of labels for polygon features involves considerable complexity. Typically, this process requires the use of algorithms to clip the polygon and identify the optimal label position based on the polygon's characteristics. Ideally, the label should be positioned near the center of the polygon and contained within its boundaries. In cases where the polygon feature is very small, the label may be placed adjacent to the feature.

Following the above configuration principles, dynamic labelling is characterized by several fundamental features:
Automated Label Placement: the label positions are automatically determined to ensure optimal placement relative to map features, minimizing potential cartographic conflicts.
Non-selectable Labels: labels are passive elements that users cannot directly interact with or manipulate.
Uniform Display Properties: the display characteristics of individual labels cannot be altered, ensuring consistency across the map.

Esri's Maplex Label Engine offers a specialized suite of tools that let you manage label placement relative to features, adjust or condense labels to maximize placement in limited spaces, and resolve conflicts between overlapping labels.