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CallbackProperty

new Cesium.CallbackProperty(callback, isConstant)
engine/Source/DataSources/CallbackProperty.js 14

A Property whose value is lazily evaluated by a callback function.
Name Type Description
callback CallbackProperty.Callback The function to be called when the property is evaluated.
isConstant boolean true when the callback function returns the same value every time, false if the value will change.

Members

readonly definitionChanged : Event
engine/Source/DataSources/CallbackProperty.js 42

Gets the event that is raised whenever the definition of this property changes. The definition is changed whenever setCallback is called.

readonly isConstant : boolean
engine/Source/DataSources/CallbackProperty.js 29

Gets a value indicating if this property is constant.

Methods

equals(other) → boolean
engine/Source/DataSources/CallbackProperty.js 94

Compares this property to the provided property and returns true if they are equal, false otherwise.
Name Type Description
other Property optional The other property.
Returns:
true if left and right are equal, false otherwise.

getValue(time, result) → object
engine/Source/DataSources/CallbackProperty.js 56

Gets the value of the property.
Name Type Description
time JulianDate The time for which to retrieve the value.
result object optional The object to store the value into, if omitted, a new instance is created and returned.
Returns:
The modified result parameter or a new instance if the result parameter was not supplied or is unsupported.

setCallback(callback, isConstant)
engine/Source/DataSources/CallbackProperty.js 66

Sets the callback to be used.
Name Type Description
callback CallbackProperty.Callback The function to be called when the property is evaluated.
isConstant boolean true when the callback function returns the same value every time, false if the value will change.

Type Definitions

Cesium.CallbackProperty.Callback(time, result) → object
engine/Source/DataSources/CallbackProperty.js 103

A function that returns the value of the property.
Name Type Description
time JulianDate The time for which to retrieve the value.
result object optional The object to store the value into. If omitted, the function must create and return a new instance.
Returns:
The modified result parameter, or a new instance if the result parameter was not supplied or is unsupported.
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