com.luciad.view.lightspeed.services.effects

LuciadLightspeedClass TLspFog

java.lang.Object

com.luciad.view.lightspeed.services.effects.ALspGraphicsEffect

com.luciad.view.lightspeed.services.effects.TLspFog

public class TLspFog
extends ALspGraphicsEffect

Graphics effect which enables fog in a 3D view. Fog provides a basic approximation of the scattering of light in the atmosphere, and can greatly increase the user's perception of depth and scale in a 3D view.

Fog is defined by a color and a visibility distance. This class decreases the amount of fog automatically as the camera gets further away from the Earth (i.e. as it "exits the atmosphere"). Fog is implemented analogous to OpenGL's fixed function fog using the GL_EXP mode. The getDensity() method computes a fog density value based on the altitude of the camera and the visibility distance.

Since:

2013.0

Constructor Summary

Constructors

Constructor and Description
TLspFog(ILspView aView) Creates a new fog effect for the given view.

Method Summary

Modifier and Type	Method and Description
Color	getColor() Returns the fog color.
double	getDensity() Returns the current fog density in the view.
double	getMaxAltitude() Returns the altitude above which fog is no longer applied.
double	getMinAltitude() Returns the altitude below which visibility due to fog is at its lowest value.
double	getVisibilityAtMinAltitude() Returns the visibility distance when the camera is at or below getMinAltitude().
void	setColor(Color aColor) Sets the fog color.
void	setMaxAltitude(double aMaxAltitude) Sets the altitude above which fog is no longer applied.
void	setMinAltitude(double aMinAltitude) Sets the altitude below which visibility due to fog is at its lowest value.
void	setVisibilityAtMinAltitude(double aVisibilityAtMinAltitude) Sets the visibility distance used when the camera is at or below getMinAltitude().

Methods inherited from class com.luciad.view.lightspeed.services.effects.ALspGraphicsEffect

addPropertyChangeListener, equals, firePropertyChange, hashCode, isEnabled, removePropertyChangeListener, setEnabled

Methods inherited from class java.lang.Object

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

Constructor Detail

TLspFog

public TLspFog(ILspView aView)

Creates a new fog effect for the given view.

Parameters:

aView - the view in which the fog will be used

Method Detail

getDensity

public double getDensity()

Returns the current fog density in the view. The density is derived from the camera position in the view. If the view is 2D, this method always returns zero. In 3D views, the density is computed based on getVisibilityAtMinAltitude() and the altitude of the camera between getMinAltitude() and getMaxAltitude(). The density fades to zero when the camera reaches the maximum altitude.

Fog is implemented analogous to OpenGL's fixed-function GL_EXP fog mode. This means that for any point in the world, a fog percentage is computed as 1.0 - exp(-d*z), where d is the fog density and z is the distance of the point to the eye.

Returns:

the current fog density in the view.

getColor

public Color getColor()

Returns the fog color.

Returns:

the fog color

setColor

public void setColor(Color aColor)

Sets the fog color.

Parameters:

aColor - the new fog color

getVisibilityAtMinAltitude

public double getVisibilityAtMinAltitude()

Returns the visibility distance when the camera is at or below getMinAltitude(). The distance is measured in world units. The default value is 100 km.

Returns:

the minimum visibility distance due to fog

setVisibilityAtMinAltitude

public void setVisibilityAtMinAltitude(double aVisibilityAtMinAltitude)

Sets the visibility distance used when the camera is at or below getMinAltitude().

Parameters:

aVisibilityAtMinAltitude - the minimum visibility distance due to fog

getMinAltitude

public double getMinAltitude()

Returns the altitude below which visibility due to fog is at its lowest value.

Returns:

the altitude below which visibility due to fog is at its lowest value

setMinAltitude

public void setMinAltitude(double aMinAltitude)

Sets the altitude below which visibility due to fog is at its lowest value.

Parameters:

aMinAltitude - the altitude at which minimum visibility is reached

getMaxAltitude

public double getMaxAltitude()

Returns the altitude above which fog is no longer applied.

Returns:

the altitude above which fog is no longer applied

setMaxAltitude

public void setMaxAltitude(double aMaxAltitude)

Sets the altitude above which fog is no longer applied.

Parameters:

aMaxAltitude - the altitude above which fog is no longer applied