CallbackPositionProperty

new Cesium.CallbackPositionProperty(callback, isConstant, referenceFrame)
engine/Source/DataSources/CallbackPositionProperty.js 21

A PositionProperty whose value is lazily evaluated by a callback function.
Name Type Default Description
callback CallbackPositionProperty.Callback The function to be called when the position property is evaluated.
isConstant boolean true when the callback function returns the same value every time, false if the value will change.
referenceFrame ReferenceFrame ReferenceFrame.FIXED optional The reference frame in which the position is defined.
Demo:

Members

readonly definitionChanged : Event
engine/Source/DataSources/CallbackPositionProperty.js 51

Gets the event that is raised whenever the definition of this property changes. The definition is considered to have changed if a call to getValue would return a different result for the same time.

readonly isConstant : boolean
engine/Source/DataSources/CallbackPositionProperty.js 37

Gets a value indicating if this property is constant.

referenceFrame : ReferenceFrame
engine/Source/DataSources/CallbackPositionProperty.js 62

Gets the reference frame in which the position is defined.
Default Value: ReferenceFrame.FIXED;

Methods

equals(other) → boolean
engine/Source/DataSources/CallbackPositionProperty.js 155

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) → Cartesian3|undefined
engine/Source/DataSources/CallbackPositionProperty.js 78

Gets the value of the property at the provided time in the fixed frame.
Name Type Default Description
time JulianDate JulianDate.now() optional The time for which to retrieve the value. If omitted, the current system time is used.
result Cartesian3 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.

getValueInReferenceFrame(time, referenceFrame, result) → Cartesian3|undefined
engine/Source/DataSources/CallbackPositionProperty.js 123

Gets the value of the property at the provided time and in the provided reference frame.
Name Type Description
time JulianDate The time for which to retrieve the value.
referenceFrame ReferenceFrame The desired referenceFrame of the result.
result Cartesian3 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.

setCallback(callback, isConstant)
engine/Source/DataSources/CallbackPositionProperty.js 91

Sets the callback to be used.
Name Type Description
callback CallbackPositionProperty.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.CallbackPositionProperty.Callback(time, result) → Cartesian3|undefined
engine/Source/DataSources/CallbackPositionProperty.js 165

A function that returns the value of the position property.
Name Type Default Description
time JulianDate JulianDate.now() optional The time for which to retrieve the value. If omitted, the current system time is used.
result Cartesian3 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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