What are layers ?
Layers are the LuciadRIA view components that process and group the objects of a model to take care of their visualization. A view typically displays more than one layer, so you can have objects from many data models on screen.
A layer defines:
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The styling for your objects
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Whether users can select objects
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Whether users can edit objects
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Whether labels are visible
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Whether objects are filtered
LuciadRIA comes with a set of pre-defined layer implementations:
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Layers that visualize raster models. See the Visualizing raster data documentation for more information.
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Layers that visualize vector features. See the Visualizing vector data documentation for more information.
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Layers that visualize a grid on the map. See the Visualizing a grid documentation for more information.
Different layer types
Associated with each layer is a LayerType.
LuciadRIA uses the LayerType to build up an efficient DOM representation, based on the logical ordering of Layer instances in the map and on the specific LayerType.
The layer types are:
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BASE: a base layer is always drawn behind all other data. This type targets raster data such as aerial photography or pre-rendered cartographic imagery. -
STATIC: a static layer indicates that the model data or the visualization properties don’t change often. -
DYNAMIC: a dynamic layer indicates that the model data or visualization properties of the data may change often, such as moving flight paths, or frequently edited data.
Common layer properties
All layers have common properties that affect the behavior of the layer and events that you can use to implement application-specific capabilities.
For example, setting the visibility property of a layer determines whether the map displays the layer or not.
For the majority of these properties, the layer also fires events when the property value changes.
For example, the visibilityChanged event is triggered when the value of the visibility property changes.