VisibilityOperator.Refraction Property

Gets or sets a value that models the effects of refraction in the atmosphere.

Syntax

public AttributeVariable< System.Double > Refraction { get; set; }

Property Value

Type: An attribute variable that returns a value of type System.Double.
Default: 1.25
A dimensionless number, by which the value of the Earth radius will be multiplied.

Remarks

The radius of the Earth will be multiplied with the value of Refraction, before the effects of the Earth curvature are computed. This gives a simple model of the refractive index of the atmosphere, which normally decreases with height, which causes rays to bend slightly downwards.

For radar systems, a common rule of thumb is to set Refraction to 1.33, although the true value can vary between 1.20 in a cold climate and 1.90 in a hot climate; see Skolnik (reference 4 below).

For optical sight, an average value of Refraction is 1.15 according to Merry (reference 2), less than 1.17 according to Schadewald (reference 3), but 1.19 according to Lynch and Livingston (reference 1).

The value of Refraction must be non-zero; otherwise an exception will be raised.

Literature

D. K. Lynch and W. Livingston, Color and Light in Nature, Cambridge University Press 1995 (2nd edition 2001), figure 2.17C.
C. Merry. Basics of levelling. Lecture notes from the 1998 GLOSS Training Course at the University of Cape Town.
R. J. Schadewald. Looking for lighthouses, in Creation/Evolution #31, 1992.
M. I. Skolnik. Introduction to Radar Systems, section 12.4. McGraw-Hill, 2nd edition 1980.

Example

// Increase the Refraction by 0.1
public static void IncreaseRefraction(VisibilityOperator visibilityOperator)
{
    // Get the current Refraction value
    double currentRefraction = 0.0;
    visibilityOperator.Refraction.TryGetValue(new AttributeSet(), out currentRefraction);

    // This property is a member of a type that might be referred to by a View 
    // or a GlobeView, either directly or indirectly through other objects, which means 
    // that you must use the Guard class to take the global configuration lock when it 
    // is modified to synchronize access with any running Carmenta Engine threads.
    using (Guard guard = new Guard())
    {
        // Increase the current Refraction by 0.1
        visibilityOperator.Refraction = currentRefraction + 0.1;
    }
}

Platforms

Windows, Linux, Android

VisibilityOperator::refraction Property

Gets or sets a value that models the effects of refraction in the atmosphere.

Syntax

C++

public:
DoubleAttributeVariablePtr refraction ( ) const;
void refraction ( const DoubleAttributeVariablePtr& value )

Property Value

Type: An attribute variable that returns a value of type double.
Default: 1.25
A dimensionless number, by which the value of the Earth radius will be multiplied.

Remarks

The radius of the Earth will be multiplied with the value of refraction, before the effects of the Earth curvature are computed. This gives a simple model of the refractive index of the atmosphere, which normally decreases with height, which causes rays to bend slightly downwards.

For radar systems, a common rule of thumb is to set refraction to 1.33, although the true value can vary between 1.20 in a cold climate and 1.90 in a hot climate; see Skolnik (reference 4 below).

For optical sight, an average value of refraction is 1.15 according to Merry (reference 2), less than 1.17 according to Schadewald (reference 3), but 1.19 according to Lynch and Livingston (reference 1).

The value of refraction must be non-zero; otherwise an exception will be raised.

Literature

D. K. Lynch and W. Livingston, Color and Light in Nature, Cambridge University Press 1995 (2nd edition 2001), figure 2.17C.
C. Merry. Basics of levelling. Lecture notes from the 1998 GLOSS Training Course at the University of Cape Town.
R. J. Schadewald. Looking for lighthouses, in Creation/Evolution #31, 1992.
M. I. Skolnik. Introduction to Radar Systems, section 12.4. McGraw-Hill, 2nd edition 1980.

Example

C++

// Increase the Refraction by 0.1
static void increaseRefraction(VisibilityOperatorPtr visibilityOperator)
{

    // Get the current Refraction value
    double currentRefraction = 0.0;
    visibilityOperator->refraction()->tryGetValue(currentRefraction, new AttributeSet());

    // This property is a member of a type that might be referred to by a View 
    // or a GlobeView, either directly or indirectly through other objects, which means 
    // that you must use the Guard class to take the global configuration lock when it 
    // is modified to synchronize access with any running Carmenta Engine threads.
    Guard guard;

    // Increase the current Refraction by 0.1
    visibilityOperator->refraction(
        new DirectDoubleAttributeVariable(currentRefraction + 0.1));
}

Platforms

Windows, Linux, Android

VisibilityOperator.refraction Property

Gets or sets a value that models the effects of refraction in the atmosphere.

Syntax

Java

public final DoubleAttributeVariable getRefraction ( );
public final void setRefraction ( DoubleAttributeVariable value );

Property Value

Type: An attribute variable that returns a value of type double.
Default: 1.25
A dimensionless number, by which the value of the Earth radius will be multiplied.

Remarks

For radar systems, a common rule of thumb is to set refraction to 1.33, although the true value can vary between 1.20 in a cold climate and 1.90 in a hot climate; see Skolnik (reference 4 below).

The value of refraction must be non-zero; otherwise an exception will be raised.

Literature

D. K. Lynch and W. Livingston, Color and Light in Nature, Cambridge University Press 1995 (2nd edition 2001), figure 2.17C.
C. Merry. Basics of levelling. Lecture notes from the 1998 GLOSS Training Course at the University of Cape Town.
R. J. Schadewald. Looking for lighthouses, in Creation/Evolution #31, 1992.
M. I. Skolnik. Introduction to Radar Systems, section 12.4. McGraw-Hill, 2nd edition 1980.

Example

Java

// Increase the Refraction by 0.1
public static void increaseRefraction(VisibilityOperator visibilityOperator)
{
    // Get the current Refraction value
    double currentRefraction =
    visibilityOperator.getRefraction().tryGetValue(new AttributeSet()).doubleValue();

    // This property is a member of a type that might be referred to by a View 
    // or a GlobeView, either directly or indirectly through other objects, which means 
    // that you must use the Guard class to take the global configuration lock when it 
    // is modified to synchronize access with any running Carmenta Engine threads.
    Guard guard = new Guard();
    try
    {
        // Increase the current Refraction by 0.1
        visibilityOperator.setRefraction(
            new DirectDoubleAttributeVariable(currentRefraction + 0.1));
    }
    finally
    {
        guard.dispose();
    }
}

Platforms

Windows, Linux, Android

VisibilityOperator.refraction Property

Gets or sets a value that models the effects of refraction in the atmosphere.

Syntax

Python

refraction

Property Value

Type: An attribute variable that returns a value of type double.
Default: 1.25
A dimensionless number, by which the value of the Earth radius will be multiplied.

Remarks

For radar systems, a common rule of thumb is to set refraction to 1.33, although the true value can vary between 1.20 in a cold climate and 1.90 in a hot climate; see Skolnik (reference 4 below).

The value of refraction must be non-zero; otherwise an exception will be raised.

Literature

D. K. Lynch and W. Livingston, Color and Light in Nature, Cambridge University Press 1995 (2nd edition 2001), figure 2.17C.
C. Merry. Basics of levelling. Lecture notes from the 1998 GLOSS Training Course at the University of Cape Town.
R. J. Schadewald. Looking for lighthouses, in Creation/Evolution #31, 1992.
M. I. Skolnik. Introduction to Radar Systems, section 12.4. McGraw-Hill, 2nd edition 1980.

Example

Python

# This example is not available in the selected language.

Platforms

Windows, Linux, Android

VisibilityOperator.Refraction Property

In this article

Syntax

Property Value

Remarks

Example

Platforms

See Also

Reference

VisibilityOperator::refraction Property

In this article

Syntax

Property Value

Remarks

Example

Platforms

See Also

Reference

VisibilityOperator.refraction Property

In this article

Syntax

Property Value

Remarks

Example

Platforms

See Also

Reference

VisibilityOperator.refraction Property

In this article

Syntax

Property Value

Remarks

Example

Platforms

See Also

Reference