TLcdLOSRadarPropagationFunctionSkyBackground (LuciadLightspeed API documentation)

java.lang.Object
- com.luciad.tea.TLcdLOSRadarPropagationFunctionSkyBackground

All Implemented Interfaces:

ILcdLOSPropagationFunction, ILcdLOSRadarPropagationFunction
```
public class TLcdLOSRadarPropagationFunctionSkyBackground
extends Object
implements ILcdLOSRadarPropagationFunction
```
Computes the minimal heights from which one is visible around the center point of a line-of-sight coverage with the sky as background. These heights are assigned along the given azimuth and stored in the polar matrix view. This implementation takes the whole horizon of the line-of-sight coverage into account while checking for terrain background. If this horizon is too close, the results will be incorrect since terrain background just outside the horizon are not taken into account.
This propagation function needs an ILcdLOSPropagationFunction on which it will base its line-of-sight computations. The radar propagation function computes the minimal heights from which one is visible. The visibility with sky in background is computed using the resulting value of the last matrix entry corresponding to the given azimuth.
The matrix resulting from this propagation function can contain the following special values:
- ILcdLOSRadarPropagationFunction.INVISIBLE: for points where the object is invisible.
- ILcdLOSRadarPropagationFunction.UNKNOWN: for points where the visibility is unknown. For example when no elevation data or invalid data was found at that point.
The following image gives a visual explanation of this propagation function. The green line denotes the result given this terrain profile and the visibility properties of the helicopter pilot. The thin black line corresponds to the line-of-sight coverage matrix, needed by this function.

Field Summary
- Fields inherited from interface com.luciad.tea.ILcdLOSRadarPropagationFunction
  INVISIBLE, UNKNOWN

Constructor Summary

Constructors
Constructor and Description
`TLcdLOSRadarPropagationFunctionSkyBackground(ILcdLOSRadarPropagationFunction aLOSRadarPropagationFunction, TLcdCoverageAltitudeMode aAltitudeMode)` Creates a propagation function which computes the minimal height from which one is visible from the center point of a circular area with the sky as background.
`TLcdLOSRadarPropagationFunctionSkyBackground(ILcdLOSRadarPropagationFunction aLOSRadarPropagationFunction, TLcdCoverageAltitudeMode aAltitudeMode, TLcdLOSOptions aLOSOption)` Creates a propagation function which computes the minimal height from which one is visible from the center point of a circular area with the sky as background.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`applyForAzimuthSFCT(double aAzimuth, ILcdLOSCoverageMatrix aLOSCoverageMatrixSFCT)` Computes the minimal heights from which one is visible around the center point of a line-of-sight coverage with the sky as background for a given azimuth and stores the resulting heights in the line-of-sight coverage matrix.
`ILcdLOSCoverageMatrix`	`createLOSCoverageMatrix(ILcdLOSCoverage aLOSCoverage, ILcdGeoReference aMatrixReference)` Creates a coverage matrix using the line-of-sight coverage `aLOSCoverage` and the matrix reference `aMatrixReference`.
`TLcdCoverageAltitudeMode`	`getAltitudeMode()` Returns the altitude mode indicating the definition of the resulting line-of-sight values.
`TLcdEarthRepresentationMode`	`getEarthRepresentationMode()` Returns the earth representation mode used by this instance.
`double`	`getKFactor()` Returns the K-factor indicating the reflection of radar waves on the atmosphere.
`double`	`getMaxRadarTiltAngle()` Returns the maximum radar tilt angle in degrees, starting from 0 at the horizontal plane to 90 at zenith.
`double`	`getMaxRadarTiltAzimuth()` Returns the azimuth in degrees where the maximum radar tilt angle occurs.
`double`	`getMaxVerticalAngle()` Returns the maximum angle of the vertical extent in degrees, starting from 0 at the ground to 180 at zenith.
`double`	`getMinVerticalAngle()` Returns the minimum angle of the vertical extent in degrees, starting from 0 at the ground to 180 at zenith.
`ALcdTerrainElevationProvider`	`getTerrainElevationProvider()` Returns the elevation provider used to retrieve the terrain elevation data.
`void`	`initialize(ILcdLOSCoverage aLOSCoverage, ILcdGeoReference aMatrixReference)` Initialize the propagation function with the given coverage `aLOSCoverage` and the given matrix reference `aMatrixReference`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - TLcdLOSRadarPropagationFunctionSkyBackground
```
public TLcdLOSRadarPropagationFunctionSkyBackground(ILcdLOSRadarPropagationFunction aLOSRadarPropagationFunction,
                                                    TLcdCoverageAltitudeMode aAltitudeMode)
```
    Creates a propagation function which computes the minimal height from which one is visible from the center point of a circular area with the sky as background. Note that the propagation function cannot be set to null. If this condition is not met, a NullPointerException will be thrown.
    Parameters:
    
    aLOSRadarPropagationFunction - The propagation function on which to base its computations.
    
    aAltitudeMode - The altitude mode indicating the definition of the resulting values.
    
    Throws:
    
    NullPointerException - when the argument aLOSRadarPropagationFunction is null.
    IllegalArgumentException -
    
    if the argument aLOSRadarPropagationFunction does not use the following earth representation mode: TLcdEarthRepresentationMode.SPHERICAL_FIXED_RADIUS or TLcdEarthRepresentationMode.SPHERICAL_EULER_RADIUS or if it uses the altitude mode TLcdCoverageAltitudeMode.ABOVE_OBJECT,
    
    if the aAltitudeMode is TLcdCoverageAltitudeMode.ABOVE_OBJECT and
    
    if the argument aKFactor is smaller than or equal to zero.
  - TLcdLOSRadarPropagationFunctionSkyBackground
```
public TLcdLOSRadarPropagationFunctionSkyBackground(ILcdLOSRadarPropagationFunction aLOSRadarPropagationFunction,
                                                    TLcdCoverageAltitudeMode aAltitudeMode,
                                                    TLcdLOSOptions aLOSOption)
```
    Creates a propagation function which computes the minimal height from which one is visible from the center point of a circular area with the sky as background. Note that the propagation function cannot be set to null. If this condition is not met, a NullPointerException will be thrown.
    Parameters:
    
    aLOSRadarPropagationFunction - The propagation function on which to base its computations.
    
    aAltitudeMode - The altitude mode indicating the definition of the resulting values.
    
    aLOSOption - A LOS option object containing parameters for the internals of this propagation function and its resulting coverages
    
    Throws:
    
    NullPointerException - when the argument aLOSRadarPropagationFunction is null.
    IllegalArgumentException -
    
    if the argument aLOSRadarPropagationFunction does not use the following earth representation mode: TLcdEarthRepresentationMode.SPHERICAL_FIXED_RADIUS or TLcdEarthRepresentationMode.SPHERICAL_EULER_RADIUS or if it uses the altitude mode TLcdCoverageAltitudeMode.ABOVE_OBJECT,
    
    if the aAltitudeMode is TLcdCoverageAltitudeMode.ABOVE_OBJECT and
    
    if the argument aKFactor is smaller than or equal to zero.
- Method Detail
  - createLOSCoverageMatrix
```
public ILcdLOSCoverageMatrix createLOSCoverageMatrix(ILcdLOSCoverage aLOSCoverage,
                                                     ILcdGeoReference aMatrixReference)
```
    Description copied from interface: ILcdLOSPropagationFunction
    
    Creates a coverage matrix using the line-of-sight coverage aLOSCoverage and the matrix reference aMatrixReference. The result of this method is used as input parameter for the method applyForAzimuthSFCT, which will store the actual matrix values. The matrix should be consistent with the given coverage. This means that all matrix rows and columns represent evenly spaced radii and azimuths as defined by the radial and angular step sizes of the line-of-sight coverage.
    The method ILcdLOSPropagationFunction.initialize(com.luciad.tea.ILcdLOSCoverage, com.luciad.reference.ILcdGeoReference) is called with the same arguments as supplied with this method.
    The ILcdLOSCoverageMatrix created by this method is guaranteed to be capable of determining its own associatedPointX and associatedPointY properties. These values are not calculated by this ILcdPropagationFunction. An ILcdLOSPropagationFunction does not modify the values of the associatedPointX and associatedPointY for its created ILcdLOSCoverageMatrix.
    
    Specified by:
    
    createLOSCoverageMatrix in interface ILcdLOSPropagationFunction
    
    Parameters:
    
    aLOSCoverage - The covered area and the intermediate step sizes.
    
    aMatrixReference - The reference in which this matrix is defined.
    
    Returns:
    
    the created coverage matrix.
  - initialize
```
public void initialize(ILcdLOSCoverage aLOSCoverage,
                       ILcdGeoReference aMatrixReference)
```
    Description copied from interface: ILcdLOSPropagationFunction
    
    Initialize the propagation function with the given coverage aLOSCoverage and the given matrix reference aMatrixReference. For performance reasons, it is recommended that this method initializes all fields that are common to all computations or which do not depend on a specific azimuth.
    
    Specified by:
    
    initialize in interface ILcdLOSPropagationFunction
    
    Parameters:
    
    aLOSCoverage - The covered area to use.
    
    aMatrixReference - The matrix reference in which to compute the matrix values.
  - applyForAzimuthSFCT
```
public void applyForAzimuthSFCT(double aAzimuth,
                                ILcdLOSCoverageMatrix aLOSCoverageMatrixSFCT)
```
    Computes the minimal heights from which one is visible around the center point of a line-of-sight coverage with the sky as background for a given azimuth and stores the resulting heights in the line-of-sight coverage matrix.
    Note that this implementation assumes that the default value of a matrix entry corresponds to the value for invisible points (which is ILcdLOSRadarPropagationFunction.INVISIBLE). Refer to the class documentation for more information about the different special values.
    
    Specified by:
    
    applyForAzimuthSFCT in interface ILcdLOSPropagationFunction
    
    Parameters:
    
    aAzimuth - The azimuth in degrees.
    
    aLOSCoverageMatrixSFCT - The coverage matrix to update.
    
    Throws:
    
    NullPointerException - if the aLOSCoverageMatrixSFCT is null.
  - getEarthRepresentationMode
```
public TLcdEarthRepresentationMode getEarthRepresentationMode()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the earth representation mode used by this instance.
    
    Specified by:
    
    getEarthRepresentationMode in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the earth representation mode used by this instance.
  - getAltitudeMode
```
public TLcdCoverageAltitudeMode getAltitudeMode()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the altitude mode indicating the definition of the resulting line-of-sight values.
    
    Specified by:
    
    getAltitudeMode in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the altitude mode indicating the definition of the resulting line-of-sight values.
  - getKFactor
```
public double getKFactor()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the K-factor indicating the reflection of radar waves on the atmosphere. For radar computations, values should be greater than 1, usually 4/3. Setting the value equal to 1 will yield the same results as visual line-of-sight computations.
    
    Specified by:
    
    getKFactor in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the K-factor indicating the reflection of radar waves on the atmosphere.
  - getMaxVerticalAngle
```
public double getMaxVerticalAngle()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the maximum angle of the vertical extent in degrees, starting from 0 at the ground to 180 at zenith. It is the maximum vertical angle when the radar tilt angle is set to zero.
    
    Specified by:
    
    getMaxVerticalAngle in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the maximum angle of the vertical extent in degrees.
  - getMinVerticalAngle
```
public double getMinVerticalAngle()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the minimum angle of the vertical extent in degrees, starting from 0 at the ground to 180 at zenith. It is the minimum vertical angle when the radar tilt angle is set to zero.
    
    Specified by:
    
    getMinVerticalAngle in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the minimum angle of the vertical extent in degrees.
  - getMaxRadarTiltAngle
```
public double getMaxRadarTiltAngle()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the maximum radar tilt angle in degrees, starting from 0 at the horizontal plane to 90 at zenith.
    
    Specified by:
    
    getMaxRadarTiltAngle in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the maximum radar tilt angle in degrees.
  - getMaxRadarTiltAzimuth
```
public double getMaxRadarTiltAzimuth()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the azimuth in degrees where the maximum radar tilt angle occurs.
    
    Specified by:
    
    getMaxRadarTiltAzimuth in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the azimuth in degrees where the maximum radar tilt angle occurs.
  - getTerrainElevationProvider
```
public ALcdTerrainElevationProvider getTerrainElevationProvider()
```
    Description copied from interface: ILcdLOSRadarPropagationFunction
    
    Returns the elevation provider used to retrieve the terrain elevation data.
    
    Specified by:
    
    getTerrainElevationProvider in interface ILcdLOSRadarPropagationFunction
    
    Returns:
    
    the elevation provider used to retrieve the terrain elevation data.

Terrain Analysis EngineClass TLcdLOSRadarPropagationFunctionSkyBackground

Field Summary

Fields inherited from interface com.luciad.tea.ILcdLOSRadarPropagationFunction

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

TLcdLOSRadarPropagationFunctionSkyBackground

TLcdLOSRadarPropagationFunctionSkyBackground

Method Detail

createLOSCoverageMatrix

initialize

applyForAzimuthSFCT

getEarthRepresentationMode

getAltitudeMode

getKFactor

getMaxVerticalAngle

getMinVerticalAngle

getMaxRadarTiltAngle

getMaxRadarTiltAzimuth

getTerrainElevationProvider