ISpatialItemsSource Interface

[This is preliminary documentation and is subject to change.]

Provides a two-dimensional index of items that can be quickly queried for all items that intersect a given rectangle.

Namespace: ZU.Semantic.Spatial
Assemblies: ZU.Core.Developer (in ZU.Core.Developer.dll) Version: 2.0.5976.27963
ZU.Core.Developer (in ZU.Core.Developer.dll) Version: 2.0.5976.27963

Syntax

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public interface ISpatialItemsSource

The ISpatialItemsSource type exposes the following members.

Properties

	Name	Description
	Extent	Gets the entire extent of the index, which is typically the union of all bounding boxes of all items within the set.

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Methods

	Name	Description
	Query	Gets the set of items that intersect the given rectangle.

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Events

	Name	Description
	ExtentChanged	Occurs when the value of the Extent property has changed.
	QueryInvalidated	Occurs when the results of the last query are no longer valid and should be re-queried.

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Remarks

When the [!:ZoomableCanvas] is hosting items for an [!:ItemsControl], the [!:ItemsControl.ItemsSource] can implement this interface to greatly speed up virtualization in the canvas. If any of those conditions are not true, then the canvas must realize every item at least once in order to determine its bounds before it can virtualize it, and then once it is virtualized it will have no means of moving spontaneously back into view.

Reference

ZU.Semantic.Spatial Namespace