org.sunflow.core.light
Class SphereLight

java.lang.Object
  extended by org.sunflow.core.light.SphereLight
All Implemented Interfaces:
LightSource, RenderObject, Shader

public class SphereLight
extends java.lang.Object
implements LightSource, Shader


Constructor Summary
SphereLight()
           
 
Method Summary
 Instance createInstance()
          Create an instance which represents the geometry of this light source.
 int getLowSamples()
           
 int getNumSamples()
          Get the maximum number of samples that can be taken from this light source.
 Color getOpacity(ShadingState state)
          Returns how much light is blocked by this shader.
 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.
 Color getRadiance(ShadingState state)
          Gets the radiance for a specified rendering state.
 void getSamples(ShadingState state)
          Samples the light source to compute direct illumination.
 boolean isOpaque()
          Returns true if this shader is fully opaque.
 boolean isVisible(ShadingState state)
           
 void scatterPhoton(ShadingState state, Color power)
          Scatter a photon with the specied power.
 boolean update(ParameterList pl, SunflowAPI api)
          Update this object given a list of parameters.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SphereLight

public SphereLight()
Method Detail

update

public boolean update(ParameterList pl,
                      SunflowAPI api)
Description copied from interface: RenderObject
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

getNumSamples

public int getNumSamples()
Description copied from interface: LightSource
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

getLowSamples

public int getLowSamples()

isVisible

public boolean isVisible(ShadingState state)

getSamples

public void getSamples(ShadingState state)
Description copied from interface: LightSource
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

getPhoton

public void getPhoton(double randX1,
                      double randY1,
                      double randX2,
                      double randY2,
                      Point3 p,
                      Vector3 dir,
                      Color power)
Description copied from interface: LightSource
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()
Description copied from interface: LightSource
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

getRadiance

public Color getRadiance(ShadingState state)
Description copied from interface: Shader
Gets the radiance for a specified rendering state. When this method is called, you can assume that a hit has been registered in the state and that the hit surface information has been computed.

Specified by:
getRadiance in interface Shader
Parameters:
state - current render state
Returns:
color emitted or reflected by the shader

scatterPhoton

public void scatterPhoton(ShadingState state,
                          Color power)
Description copied from interface: Shader
Scatter a photon with the specied power. Incoming photon direction is specified by the ray attached to the current render state. This method can safely do nothing if photon scattering is not supported or relevant for the shader type.

Specified by:
scatterPhoton in interface Shader
Parameters:
state - current state
power - power of the incoming photon.

createInstance

public Instance createInstance()
Description copied from interface: LightSource
Create an instance which represents the geometry of this light source. This instance will be created just before and removed immediately after rendering. Non-area light sources can return null to indicate that no geometry needs to be created.

Specified by:
createInstance in interface LightSource
Returns:
an instance describing the light source

isOpaque

public boolean isOpaque()
Description copied from interface: Shader
Returns true if this shader is fully opaque. This gives a quick way to find out if a shader needs further processing when hit by a shadow ray.

Specified by:
isOpaque in interface Shader

getOpacity

public Color getOpacity(ShadingState state)
Description copied from interface: Shader
Returns how much light is blocked by this shader.

Specified by:
getOpacity in interface Shader