gov.nasa.worldwind.layers
Interface Layer

All Superinterfaces:

AVList, Disposable, EventListener, MessageListener, PropertyChangeListener, Restorable, WWObject

All Known Subinterfaces:

AirspaceEditor

All Known Implementing Classes:

AbstractAirspaceEditor, AbstractGraticuleLayer, AbstractLayer, AbstractShapeEditor, AirspaceLayer, AnnotationLayer, BasicMercatorTiledImageLayer, BasicTiledImageLayer, BMNGOneImage, BMNGWMSLayer, BoxEditor, CachedRenderableLayer, CompassLayer, ConeEditor, CountryBoundariesLayer, CrosshairLayer, CylinderEditor, ExtrudedPolygonEditor, GliderImageLayer, IconLayer, LandsatI3WMSLayer, LatLonGraticuleLayer, LayerManagerLayer, LocalRasterServerLayer, MarkerLayer, MarkersOrder.AppFrame.TimedMarkerLayer, MeasureTool.CustomRenderableLayer, MercatorTiledImageLayer, MGRSGraticuleLayer, MSVirtualEarthLayer, NASAWFSPlaceNameLayer, OpenStreetMapShapefileLoader.TextAndShapesLayer, OSMCycleMapLayer, OSMMapnikLayer, PickFrustum.PickFrustumLayer, PlaceNameLayer, PolygonEditor, PyramidEditor, RenderableLayer, RigidShapeEditor, RPFTiledImageLayer, ScalebarLayer, ScankortDenmarkImageLayer, SegmentPlaneEditor, SkyColorLayer, SkyGradientLayer, SphereAirspaceEditor, StarsLayer, StatusLayer, StatusLayer.StatusMGRSLayer, StatusLayer.StatusUTMLayer, SurfaceImageLayer, TerrainProfileLayer, TiledImageLayer, USDANAIPWMSImageLayer, USGSDigitalOrtho, USGSTopoHighRes, USGSTopoLowRes, USGSTopoMedRes, USGSUrbanAreaOrtho, UTMBaseGraticuleLayer, UTMGraticuleLayer, ViewControlsLayer, ViewVolumeViewer.SectorGeometryLayer, ViewVolumeViewer.ViewVolumeLayer, WedgeEditor, WMSTiledImageLayer, WorldMapLayer

public interface Layer
extends WWObject, Disposable, Restorable

Method Summary

long	getExpiryTime() Returns the current expiry time.
double	getMaxActiveAltitude() Returns the maximum altitude at which to display the layer.
Double	getMaxEffectiveAltitude(Double radius) Indicates the altitude above which this layer likely has low value or is not expected to be active.
double	getMinActiveAltitude() Returns the minimum altitude at which the layer is displayed.
Double	getMinEffectiveAltitude(Double radius) Indicates the altitude below which this layer likely has low value or is not expected to be active.
String	getName() Returns the layer's name, as specified in the most recent call to setName(java.lang.String).
double	getOpacity() Returns the layer's opacity, the degree to which it is blended with underlying layers.
double	getScale() Returns the map scale, in terms of the ratio of 1 to the value returned, e.g., 1:24000.
boolean	isAtMaxResolution() Indicates whether the most recent rendering of the layer rendered the highest resolution imagery or other data available.
boolean	isEnabled() Indicates whether the layer is enabled for rendering and selection.
boolean	isLayerActive(DrawContext dc) Indicates whether the layer is active based on arbitrary criteria.
boolean	isLayerInView(DrawContext dc) Indicates whether the layer is in the view.
boolean	isMultiResolution() Indicates whether the layer provides multiple resolutions of imagery or other data.
boolean	isNetworkRetrievalEnabled() Indicates whether the layer is allowed to retrieve data from the network.
boolean	isPickEnabled() Indicates whether the layer performs selection during picking.
void	pick(DrawContext dc, Point pickPoint) Cause the layer to perform picking, which determines whether the object or its components intersect a given point on the screen.
void	preRender(DrawContext dc) Causes the layer to perform any actions necessary to subsequently render the layer.
void	render(DrawContext dc) Cause the layer to draw its representation.
void	setEnabled(boolean enabled) Controls whether the layer is enabled for rendering and selection.
void	setExpiryTime(long expiryTime) Specifies the time of the layer's most recent dataset update.
void	setMaxActiveAltitude(double maxActiveAltitude) Specifies the maximum altitude at which to display the layer.
void	setMinActiveAltitude(double minActiveAltitude) Specifies the minimum altitude at which to display the layer.
void	setName(String name) Set the layer's name.
void	setNetworkRetrievalEnabled(boolean networkRetrievalEnabled) Controls whether the layer is allowed to retrieve data from the network.
void	setOpacity(double opacity) Sets the layer's opacity, the degree to which it is blended with underlying layers.
void	setPickEnabled(boolean isPickable) Controls whether the layer should perform picking.

Methods inherited from interface gov.nasa.worldwind.avlist.AVList

addPropertyChangeListener, addPropertyChangeListener, clearList, copy, firePropertyChange, firePropertyChange, getEntries, getStringValue, getValue, getValues, hasKey, removeKey, removePropertyChangeListener, removePropertyChangeListener, setValue, setValues

Methods inherited from interface java.beans.PropertyChangeListener

propertyChange

Methods inherited from interface gov.nasa.worldwind.event.MessageListener

onMessage

Methods inherited from interface gov.nasa.worldwind.Disposable

dispose

Methods inherited from interface gov.nasa.worldwind.Restorable

getRestorableState, restoreState

Method Detail

getExpiryTime

long getExpiryTime()

Returns the current expiry time.

Returns:

the current expiry time.

getMaxActiveAltitude

double getMaxActiveAltitude()

Returns the maximum altitude at which to display the layer.

Returns:

the maximum altitude at which to display the layer.

getMaxEffectiveAltitude

Double getMaxEffectiveAltitude(Double radius)

Indicates the altitude above which this layer likely has low value or is not expected to be active. This value is independent of the maximum active altitude, setMaxActiveAltitude(double) and does not reflect it.

The returned altitude is valid when the field of view indicated by View.getFieldOfView() is set to its default value. Changing the field of view to any value other than the default may change this layer's maximum effective altitude, but the returned altitude will not reflect that change.

Parameters:

radius - the radius of the Globe the layer is associated with. May be null, in which case the Earth's equatorial radius is used, Earth.WGS84_EQUATORIAL_RADIUS.

Returns:

the layer's maximum effective altitude.

getMinActiveAltitude

double getMinActiveAltitude()

Returns the minimum altitude at which the layer is displayed.

Returns:

the minimum altitude at which the layer is displayed.

getMinEffectiveAltitude

Double getMinEffectiveAltitude(Double radius)

Indicates the altitude below which this layer likely has low value or is not expected to be active. This value is independent of the minimum active altitude, setMinActiveAltitude(double) and does not reflect it.

The returned altitude is valid when the field of view indicated by View.getFieldOfView() is set to its default value. Changing the field of view to any value other than the default may change this layer's minimum effective altitude, but the returned altitude will not reflect that change.

Parameters:

radius - the radius of the Globe the layer is associated with. May be null, in which case the Earth's equatorial radius is used, Earth.WGS84_EQUATORIAL_RADIUS.

Returns:

the layer's minimum effective altitude.

getName

String getName()

Returns the layer's name, as specified in the most recent call to setName(java.lang.String).

Returns:

the layer's name.

getOpacity

double getOpacity()

Returns the layer's opacity, the degree to which it is blended with underlying layers.

Many layers apply special usage of opacity, and some ignore it in favor of the opacity settings of their internal renderables. See the description of this method in specific layers to determine usage there.

Returns:

The layer's opacity, a value between 0 and 1.

getScale

double getScale()

Returns the map scale, in terms of the ratio of 1 to the value returned, e.g., 1:24000.

Returns:

the map scale.

isAtMaxResolution

boolean isAtMaxResolution()

Indicates whether the most recent rendering of the layer rendered the highest resolution imagery or other data available. Some layers do not track resolution. For those layers this value will always be true. Typically such layers also return false from isMultiResolution().

Returns:

true if the layer is at maximum resolution, otherwise false.

isEnabled

boolean isEnabled()

Indicates whether the layer is enabled for rendering and selection.

Returns:

true if the layer is enabled, else false.

isLayerActive

boolean isLayerActive(DrawContext dc)

Indicates whether the layer is active based on arbitrary criteria. The method implemented here is a default indicating the layer is active if the current altitude is within the layer's min and max active altitudes. Subclasses able to consider more criteria should override this implementation.

Parameters:

dc - the current draw context

Returns:

true if the layer is active, false otherwise.

isLayerInView

boolean isLayerInView(DrawContext dc)

Indicates whether the layer is in the view. The method implemented here is a default indicating the layer is in view. Subclasses able to determine their presence in the view should override this implementation.

Parameters:

dc - the current draw context

Returns:

true if the layer is in the view, false otherwise.

isMultiResolution

boolean isMultiResolution()

Indicates whether the layer provides multiple resolutions of imagery or other data.

Returns:

true if the layer provides multiple resolutions, else false.

isNetworkRetrievalEnabled

boolean isNetworkRetrievalEnabled()

Indicates whether the layer is allowed to retrieve data from the network. Many layers have no need to retrieve data from the network. This state is meaningless for such layers.

Returns:

true if the layer is enabled to retrieve network data, else false.

isPickEnabled

boolean isPickEnabled()

Indicates whether the layer performs selection during picking.

Most layers enable picking by default. However, this becomes inconvenient for SurfaceImage and SurfaceImageLayer} when the image covers a large area because the view input handlers detect the surface image rather than the terrain as the top picked object, and will not respond to the user's attempts at navigation. The solution is to disable picking for the layer.

Returns:

true if picking is enabled, else false.

pick

void pick(DrawContext dc,
          Point pickPoint)

Cause the layer to perform picking, which determines whether the object or its components intersect a given point on the screen. Objects that intersect that point are added to the draw context's pick list and are conveyed to the application via selection events or by a direct query of WorldWindow.getObjectsAtCurrentPosition().

Parameters:

dc - the current draw context for rendering.

pickPoint - the screen coordinate point

See Also:

SelectEvent

preRender

void preRender(DrawContext dc)

Causes the layer to perform any actions necessary to subsequently render the layer. The layer has exclusive access to the frame buffer during the call, and may use it to generate images or other information that is subsequently used to render the layer's contents. Upon return, the OpenGL state must be restored to its original.

Parameters:

dc - the current draw context.

render

void render(DrawContext dc)

Cause the layer to draw its representation.

Parameters:

dc - the current draw context for rendering.

setEnabled

void setEnabled(boolean enabled)

Controls whether the layer is enabled for rendering and selection.

Parameters:

enabled - true if the layer is enabled, else false.

setExpiryTime

void setExpiryTime(long expiryTime)

Specifies the time of the layer's most recent dataset update. If greater than zero, the layer ignores and eliminates any previously cached data older than the time specified, and requests new information from the data source. If zero, the layer uses any expiry times intrinsic to the layer, typically initialized at layer construction. The default expiry time is 0, thereby enabling a layer's intrinsic expiration criteria.

Parameters:

expiryTime - the expiry time of any cached data, expressed as a number of milliseconds beyond the epoch.

See Also:

for a description of milliseconds beyond the epoch.

setMaxActiveAltitude

void setMaxActiveAltitude(double maxActiveAltitude)

Specifies the maximum altitude at which to display the layer.

Parameters:

maxActiveAltitude - the maximum altitude at which to display the layer.

setMinActiveAltitude

void setMinActiveAltitude(double minActiveAltitude)

Specifies the minimum altitude at which to display the layer.

Parameters:

minActiveAltitude - the minimum altitude at which to display the layer.

setName

void setName(String name)

Set the layer's name. The name is a convenience attribute typically used to identify the layer in user interfaces. By default, a layer has no name.

Parameters:

name - the name to assign to the layer.

setNetworkRetrievalEnabled

void setNetworkRetrievalEnabled(boolean networkRetrievalEnabled)

Controls whether the layer is allowed to retrieve data from the network. Many layers have no need for data from the network. This state may be set but is meaningless for such layers.

Parameters:

networkRetrievalEnabled - true if network retrieval is allowed, else false.

setOpacity

void setOpacity(double opacity)

Sets the layer's opacity, the degree to which it is blended with underlying layers.

Many layers apply special usage of opacity, and some ignore it in favor of the opacity settings of their internal renderables. See the description of this method in specific layers to determine usage there.

Parameters:

opacity - The layer opacity, a value between 0 and 1. 0 indicates non-opaque (fully transparent), 1 indicates fully opaque. Values between 0 and 1 indicate partial opacity.

setPickEnabled

void setPickEnabled(boolean isPickable)

Controls whether the layer should perform picking.

Parameters:

isPickable - true if the layer should perform picking, else false.