agi.foundation.geometry

(agi.foundation.models-2025r1.jar)

Class ScalarDeltaSphericalElement

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.geometry.Scalar

agi.foundation.geometry.ScalarDeltaSphericalElement

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class ScalarDeltaSphericalElement
extends Scalar

A Scalar that computes the difference in the clock or cone angle, or the difference of the the radius between two Points relative to a common parent. Note that if Element (get / set) is set to SphericalElement.CONE, there will be a discontinuity if one of the elements moves through the 0/360 degree angle. This can be thought of as computing the difference in declination or right ascension between the two points.

Constructor Summary

Constructors

Modifier	Constructor and Description
	ScalarDeltaSphericalElement() Initializes a new instance.
	ScalarDeltaSphericalElement(Point satellitePoint, CentralBody primaryCentralBody, CentralBody otherCentralBody, SphericalElement element) Initializes a new instance.
	ScalarDeltaSphericalElement(Point fromPoint, Point vertex, Point toPoint, ReferenceFrame frame, SphericalElement element) Initializes a new instance.
protected	ScalarDeltaSphericalElement(ScalarDeltaSphericalElement existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(Scalar other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(ScalarDeltaSphericalElement other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
Object	clone(CopyContext context) Clones this object using the specified context.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
SphericalElement	getElement() Gets which SphericalElement to compute.
ScalarEvaluator	getEvaluator(EvaluatorGroup group) Gets an evaluator that can be used to find the value of this scalar function at a given JulianDate.
ReferenceFrame	getFrame() Gets the ReferenceFrame that the FromPoint (get / set) and the ToPoint (get / set) will be evaluated in.
Point	getFromPoint() Gets the initial point to measure the angle from.
Point	getToPoint() Gets the other Point to compute the multi-body value with.
Point	getVertex() Gets the vertex between the FromPoint (get / set) and the ToPoint (get / set).
void	setElement(SphericalElement value) Sets which SphericalElement to compute.
void	setFrame(ReferenceFrame value) Sets the ReferenceFrame that the FromPoint (get / set) and the ToPoint (get / set) will be evaluated in.
void	setFromPoint(Point value) Sets the initial point to measure the angle from.
void	setToPoint(Point value) Sets the other Point to compute the multi-body value with.
void	setVertex(Point value) Sets the vertex between the FromPoint (get / set) and the ToPoint (get / set).

Methods inherited from class agi.foundation.geometry.Scalar

add, add, add, add, add, checkForSameDefinition, createScalarDerivative, divide, divide, divide, divide, divide, getEvaluator, multiply, multiply, multiply, multiply, multiply, power, subtract, subtract, subtract, subtract, subtract, toScalar

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, freezeAggregatedObjects, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ScalarDeltaSphericalElement

public ScalarDeltaSphericalElement()

Initializes a new instance. The FromPoint (get / set), Vertex (get / set) and ToPoint (get / set) must all be set before the evaluator can be created.

ScalarDeltaSphericalElement

public ScalarDeltaSphericalElement(Point fromPoint,
                                   Point vertex,
                                   Point toPoint,
                                   ReferenceFrame frame,
                                   @Nonnull
                                   SphericalElement element)

Initializes a new instance.

Parameters:

fromPoint - The point to measure the angle from.

vertex - The common Point between fromPoint and toPoint.

toPoint - The other Point that completes the angle.

frame - The ReferenceFrame to observe the points in.

element - Which SphericalElement to compute the difference of.

ScalarDeltaSphericalElement

public ScalarDeltaSphericalElement(Point satellitePoint,
                                   @Nonnull
                                   CentralBody primaryCentralBody,
                                   @Nonnull
                                   CentralBody otherCentralBody,
                                   @Nonnull
                                   SphericalElement element)

Initializes a new instance. The Frame (get / set) will be set to the InertialFrame (get / set) of the primaryCentralBody.

Parameters:

satellitePoint - The primary Point to subtract the Spherical element of the CenterOfMassPoint (get / set) of the otherCentralBody from.

primaryCentralBody - The common CentralBody between satellitePoint and otherCentralBody.

otherCentralBody - The other CentralBody to complete the angle between the satellitePoint and the primaryCentralBody.

element - Which SphericalElement to compute the difference of.

ScalarDeltaSphericalElement

protected ScalarDeltaSphericalElement(@Nonnull
                                      ScalarDeltaSphericalElement existingInstance,
                                      @Nonnull
                                      CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

clone

public Object clone(CopyContext context)

Clones this object using the specified context.

This method should be implemented to call a copy constructor on the class of the object being cloned. The copy constructor should take the CopyContext as a parameter in addition to the existing instance to copy. The copy constructor should first call CopyContext.addObjectMapping(T, T) to identify the newly constructed instance as a copy of the existing instance. It should then copy all fields, using CopyContext.updateReference(T) to copy any reference fields.

A typical implementation of ICloneWithContext:

public static class MyClass implements ICloneWithContext {
    public MyClass(MyClass existingInstance, CopyContext context) {
        context.addObjectMapping(existingInstance, this);
        someReference = context.updateReference(existingInstance.someReference);
    }

    @Override
    public final Object clone(CopyContext context) {
        return new MyClass(this, context);
    }

    private Object someReference;
}

In general, all fields that are reference types should be copied with a call to CopyContext.updateReference(T). There are a couple of exceptions:

1. Fields that are aggregate parts of the object should always be copied. A referenced object is an aggregate if properties or methods on the object being copied can modify the externally-visible value of the referenced object.
2. If the semantics of the referenced object require that it have a single parent, owner, context, etc., and the object being copied is that parent, owner, or context, then the referenced object should always be copied.

If one of these exceptions applies, the CopyContext should be given an opportunity to update the reference before the reference is copied explicitly. Use CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns the original object, indicating that the context does not have a replacement registered, then copy the object manually by invoking a Clone method, a copy constructor, or by manually constructing a new instance and copying the values.

alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
    alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}

If you are implementing an evaluator (a class that implements IEvaluator), the IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the copy context constructor. Code duplication can be avoided by doing the following:

1. For references to other evaluators ONLY, simply assign the reference in the constructor instead of calling CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to non-evaluators.
2. Call IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the same CopyContext passed to the constructor.
3. Implement IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.

public MyClass(MyClass existingInstance, CopyContext context) {
    super(existingInstance, context);
    someReference = context.updateReference(existingInstance.someReference);
    evaluatorReference = existingInstance.evaluatorReference;
    updateEvaluatorReferences(context);
}

@Override
public void updateEvaluatorReferences(CopyContext context) {
    evaluatorReference = context.updateReference(evaluatorReference);
}

@Override
public Object clone(CopyContext context) {
    return new MyClass(this, context);
}

private Object someReference;
private IEvaluator evaluatorReference;

Specified by:

clone in interface ICloneWithContext

Specified by:

clone in class DefinitionalObject

Parameters:

context - The context to use to perform the copy.

Returns:

A new instance which is a copy of this object.

checkForSameDefinition

protected final boolean checkForSameDefinition(Scalar other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class Scalar

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected boolean checkForSameDefinition(ScalarDeltaSphericalElement other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the ScalarDeltaSphericalElement.checkForSameDefinition(agi.foundation.geometry.Scalar) method.

Overrides:

computeCurrentDefinitionHashCode in class Scalar

Returns:

The computed hash code.

enumerateDependencies

public void enumerateDependencies(DependencyEnumerator enumerator)

Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.

Specified by:

enumerateDependencies in interface IEnumerateDependencies

Overrides:

enumerateDependencies in class DefinitionalObject

Parameters:

enumerator - The enumerator that is informed of the dependencies of this object.

getFrame

public final ReferenceFrame getFrame()

Gets the ReferenceFrame that the FromPoint (get / set) and the ToPoint (get / set) will be evaluated in.

setFrame

public final void setFrame(ReferenceFrame value)

Sets the ReferenceFrame that the FromPoint (get / set) and the ToPoint (get / set) will be evaluated in.

getVertex

public final Point getVertex()

Gets the vertex between the FromPoint (get / set) and the ToPoint (get / set).

setVertex

public final void setVertex(Point value)

Sets the vertex between the FromPoint (get / set) and the ToPoint (get / set).

getToPoint

public final Point getToPoint()

Gets the other Point to compute the multi-body value with.

setToPoint

public final void setToPoint(Point value)

Sets the other Point to compute the multi-body value with.

getFromPoint

public final Point getFromPoint()

Gets the initial point to measure the angle from.

setFromPoint

public final void setFromPoint(Point value)

Sets the initial point to measure the angle from.

getElement

@Nonnull
public final SphericalElement getElement()

Gets which SphericalElement to compute. The clock corresponds to the Right Ascension, and the cone corresponds to the Declination.

setElement

public final void setElement(@Nonnull
                             SphericalElement value)

Sets which SphericalElement to compute. The clock corresponds to the Right Ascension, and the cone corresponds to the Declination.

getEvaluator

public ScalarEvaluator getEvaluator(EvaluatorGroup group)

Gets an evaluator that can be used to find the value of this scalar function at a given JulianDate. Adds the evaluator to the EvaluatorGroup.

Specified by:

getEvaluator in class Scalar

Parameters:

group - The group with which to associate the new evaluator. By grouping evaluators that are often evaluated at the same Julian dates, common computations can be performed only once for the entire group instead of multiple times for each evaluator.

Returns:

An evaluator for this scalar.