org.sunflow.core.light

Class PointLight

Implemented Interfaces:
LightSource, RenderObject

public class PointLight
extends java.lang.Object
implements LightSource

Constructor Summary

PointLight()

Method Summary

int
getNumSamples()
Get the maximum number of samples that can be taken from this light source.
void
getPhoton(double randX1, double randY1, double randX2, double randY2, Point3 p, Vector3 dir, Color power)
Gets a photon to emit from this light source by setting each of the arguments.
float
getPower()
Get the total power emitted by this light source.
void
getSamples(ShadingState state)
Samples the light source to compute direct illumination.
boolean
update(ParameterList pl, SunflowAPI api)
Update this object given a list of parameters.

Constructor Details

PointLight

public PointLight()

Method Details

getNumSamples

public int getNumSamples()
Get the maximum number of samples that can be taken from this light source. This is currently only used for statistics reporting.
Specified by:
getNumSamples in interface LightSource
Returns:
maximum number of samples to be taken from this light source

getPhoton

public void getPhoton(double randX1,
                      double randY1,
                      double randX2,
                      double randY2,
                      Point3 p,
                      Vector3 dir,
                      Color power)
Gets a photon to emit from this light source by setting each of the arguments. The two sampling parameters are points on the unit square that can be used to sample a position and/or direction for the emitted photon.
Specified by:
getPhoton in interface LightSource
Parameters:
randX1 - sampling parameter
randY1 - sampling parameter
randX2 - sampling parameter
randY2 - sampling parameter
p - position to shoot the photon from
dir - direction to shoot the photon in
power - power of the photon

getPower

public float getPower()
Get the total power emitted by this light source. Lights that have 0 power will not emit any photons.
Specified by:
getPower in interface LightSource
Returns:
light source power

getSamples

public void getSamples(ShadingState state)
Samples the light source to compute direct illumination. Light samples can be created using the LightSample class and added to the current ShadingState. This method is responsible for the shooting of shadow rays which allows for non-physical lights that don't cast shadows. It is recommended that only a single shadow ray be shot if ShadingState.getDiffuseDepth() is greater than 0. This avoids an exponential number of shadow rays from being traced.
Specified by:
getSamples in interface LightSource
Parameters:
state - current state, including point to be shaded
See Also:
LightSample

update

public boolean update(ParameterList pl,
                      SunflowAPI api)
Update this object given a list of parameters. This method is guarenteed to be called at least once on every object, but it should correctly handle empty parameter lists. This means that the object should be in a valid state from the time it is constructed. This method should also return true or false depending on whether the update was succesfull or not.
Specified by:
update in interface RenderObject
Parameters:
pl - list of parameters to read from
api - reference to the current scene
Returns:
true if the update is succesfull, false otherwise