com.luciad.lucy.addons.tea.viewshed

LuciadLightspeedClass TLcyViewshedBackEnd

java.lang.Object

com.luciad.lucy.addons.tea.ALcyTEABackEnd

com.luciad.lucy.addons.tea.viewshed.TLcyViewshedBackEnd

public class TLcyViewshedBackEnd
extends ALcyTEABackEnd

Back-end functionality for a TEA viewshed add-on. It provides the following functionality to calculate viewsheds:

• Creating a viewshed for a set of properties.
• Creating a composite viewshed for a list of viewsheds
• Creating a viewshed raster for a set of properties.

To add support for custom models, override the createViewshed(com.luciad.lucy.util.properties.ALcyProperties, java.util.List)

and create viewsheds for your own models. These can be composited with the default return value of the method.

Since:

11.0

See Also:

ALcyTEABackEnd

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALTITUDE_TYPE_KEY The property name for the altitude type of a viewshed.
static String	ARC_ANGLE_KEY The property name for a viewshed's arc angle.
static String	AREA_BOUNDS_LIST_KEY The property name for the list of areas used for the viewshed calculations.
static String	EYEPOINT_KEY The property name for an eyepoint.
static String	EYEPOINT_REFERENCE_KEY The property name for model reference of the property value represented by EYEPOINT_KEY The associated property value is of type ILcdGeoReference.
static String	FIXED_HEIGHT_OFFSET_KEY The key used to identify the fixed height offset which is used when sampling the generated viewshed using a viewshed raster.
static String	MAX_VERTICAL_ANGLE_KEY The property name for a viewshed's maximum vertical angle.
static String	MIN_VERTICAL_ANGLE_KEY The property name for a viewshed's minimum vertical angle.
static String	MODELS_KEY The property name of the models which will be used to calculate the viewshed.
static String	START_ANGLE_KEY The property name for a viewshed's start angle.
static String	VIEWSHED_KEY The property name for the viewshed.
static String	VIEWSHED_MODEL_KEY The property name for the model of the viewshed.

Fields inherited from class com.luciad.lucy.addons.tea.ALcyTEABackEnd

ALTITUDE_PROVIDER_KEY, DISPLAY_NAME_KEY, MODEL_DISPLAY_NAME_KEY, MODEL_REFERENCE_KEY, QUALITY_KEY, SHAPE_KEY, SHAPE_REFERENCE_KEY, SOURCE_NAME_KEY, TARGET_REFERENCE_KEY, VIEW_KEY

Constructor Summary

Constructors

Constructor and Description
TLcyViewshedBackEnd(ILcyLucyEnv aLucyEnv) Default constructor for the viewshed back-end.

Method Summary

Modifier and Type	Method and Description
ILcdViewshed	createCompositeViewshed(List<ILcdViewshed> aViewshedList) Creates a composite for a given list of viewsheds.
ILcdModelDescriptor	createModelDescriptor(ALcyProperties aProperties) Returns a model descriptor suitable for the add-on's used models.
TLcdViewshedMultilevelRaster	createMultilevelRaster(ALcyProperties aProperties) Creates a multilevel raster for a given properties object.
ILcdViewshed	createViewshed(ALcyProperties aProperties, List<ILcdModel> aUsedModelsSFCT) Creates a viewshed for a single eyepoint.

Methods inherited from class com.luciad.lucy.addons.tea.ALcyTEABackEnd

createAltitudeDescriptor, createAltitudeMatrixViewFactory, createAltitudeProvider, getLucyEnv

Methods inherited from class java.lang.Object

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

Field Detail

EYEPOINT_KEY

public static final String EYEPOINT_KEY

The property name for an eyepoint. The associated property value is of type ILcdPoint.

See Also:

Constant Field Values

EYEPOINT_REFERENCE_KEY

public static final String EYEPOINT_REFERENCE_KEY

The property name for model reference of the property value represented by EYEPOINT_KEY The associated property value is of type ILcdGeoReference.

See Also:

Constant Field Values

AREA_BOUNDS_LIST_KEY

public static final String AREA_BOUNDS_LIST_KEY

The property name for the list of areas used for the viewshed calculations. The asociated property value is a list of TLcyDomainObjectContext instances, each with an ILcdBounded instance as its domain object.

See Also:

Constant Field Values

MODELS_KEY

public static final String MODELS_KEY

The property name of the models which will be used to calculate the viewshed. The associated property value is an array of ILcdModels

See Also:

Constant Field Values

VIEWSHED_KEY

public static final String VIEWSHED_KEY

The property name for the viewshed. The associated property value is of type ILcdViewshed

See Also:

Constant Field Values

VIEWSHED_MODEL_KEY

public static final String VIEWSHED_MODEL_KEY

The property name for the model of the viewshed. The associated property value is of type ILcdModel

See Also:

Constant Field Values

ALTITUDE_TYPE_KEY

public static final String ALTITUDE_TYPE_KEY

The property name for the altitude type of a viewshed. The associated property value is a String. It can be either "REGULAR" or "SUN_POSITION".

See Also:

Constant Field Values

START_ANGLE_KEY

public static final String START_ANGLE_KEY

The property name for a viewshed's start angle. The associated property value is of type double, expressed in radians.

See Also:

Constant Field Values

ARC_ANGLE_KEY

public static final String ARC_ANGLE_KEY

The property name for a viewshed's arc angle. The associated property value is of type double, expressed in radians.

See Also:

Constant Field Values

MIN_VERTICAL_ANGLE_KEY

public static final String MIN_VERTICAL_ANGLE_KEY

The property name for a viewshed's minimum vertical angle. The associated property value is of type double, expressed in radians.

See Also:

Constant Field Values

MAX_VERTICAL_ANGLE_KEY

public static final String MAX_VERTICAL_ANGLE_KEY

The property name for a viewshed's maximum vertical angle. The associated property value is of type double, expressed in radians.

See Also:

Constant Field Values

FIXED_HEIGHT_OFFSET_KEY

public static final String FIXED_HEIGHT_OFFSET_KEY

The key used to identify the fixed height offset which is used when sampling the generated viewshed using a viewshed raster. The associated property value is a double, expressed in meters.

See Also:

Constant Field Values

Constructor Detail

TLcyViewshedBackEnd

public TLcyViewshedBackEnd(ILcyLucyEnv aLucyEnv)

Default constructor for the viewshed back-end.

Parameters:

aLucyEnv - the Lucy environment for which the back-end will be used

Method Detail

createModelDescriptor

public ILcdModelDescriptor createModelDescriptor(ALcyProperties aProperties)

Returns a model descriptor suitable for the add-on's used models.

Specified by:

createModelDescriptor in class ALcyTEABackEnd

Parameters:

aProperties - a properties object with the following parameters:

• ALcyTEABackEnd.SOURCE_NAME_KEY: The source name that was used to retrieve the data from, use null to indicate that it was created from scratch.
• ALcyTEABackEnd.DISPLAY_NAME_KEY: the display name that the model descriptor should use @return a suitable model descriptor

Returns:

a viewshed model descriptor

createViewshed

public ILcdViewshed createViewshed(ALcyProperties aProperties,
                                   List<ILcdModel> aUsedModelsSFCT)

Creates a viewshed for a single eyepoint.

The following properties are supplied in the aProperties object:

• MODELS_KEY: An array of models for which the viewshed calculation occurs.
• EYEPOINT_KEY: The eyepoint which for which a viewshedneeds to be created
• EYEPOINT_REFERENCE_KEY: The reference of the eyepoint which for which a viewshed needs to be created
• AREA_BOUNDS_LIST_KEY: A list of bounds(as TLcyDomainObjectContext instances that should be used for the viewshed calculations.
• VIEWSHED_MODEL_KEY: The reference of the model in which the viewshed resides. This is not the same as the reference of the actual viewshed.
• ALTITUDE_TYPE_KEY: The altitude type of the given eyepoint
• MIN_VERTICAL_ANGLE_KEY, the minumum vertical angle (used for cone of silence)
• MAX_VERTICAL_ANGLE_KEY, the maximum vertical angle (used for cone of silence)
• START_ANGLE_KEY, the start angle (used for cone of silence)
• ARC_ANGLE_KEY, the arc angle (used for cone of silence)
• ALcyTEABackEnd.QUALITY_KEY, the step size in meters for terrain

Parameters:

aProperties - A properties file containing the properties described above.

aUsedModelsSFCT - An empty list of models that gets filled at the end of this method with the models that were used to create this viewshed.

Returns:

A valid viewshed for the given properties.

createCompositeViewshed

public ILcdViewshed createCompositeViewshed(List<ILcdViewshed> aViewshedList)

Creates a composite for a given list of viewsheds.

Parameters:

aViewshedList - A list of viewsheds that were computed using createViewshed(com.luciad.lucy.util.properties.ALcyProperties, java.util.List).

Returns:

A composite viewshed. Or null if the viewshed list was empty or null.

createMultilevelRaster

public TLcdViewshedMultilevelRaster createMultilevelRaster(ALcyProperties aProperties)

Creates a multilevel raster for a given properties object.

The following properties are supplied in the aProperties object:

• MODELS_KEY: An array of models for which the viewshed calculation occurs.
• AREA_BOUNDS_LIST_KEY: A list of bounds(as TLcyDomainObjectContext instances that should be used for the viewshed calculations.
• VIEWSHED_MODEL_KEY: The reference of the model in which the viewshed resides. This is not the same as the reference of the actual viewshed.
• ALcyTEABackEnd.QUALITY_KEY, the step size in meters for terrain
• FIXED_HEIGHT_OFFSET_KEY, the offset (in meters) with which the viewshed should be sampled above terrain.
• VIEWSHED_KEY, the viewshed for which a viewshed raster should be created

Parameters:

aProperties - A properties file containing the properties described above.

Returns:

A valid TLcdViewshedMultilevelRaster for the given properties. This method returns null if the viewshed was null. This is usually due to the viewshed being cancelled.