de.grogra.imp3d
Class Camera

java.lang.Object
  extended by de.grogra.imp3d.CameraBase
      extended by de.grogra.imp3d.Camera
All Implemented Interfaces:
Manageable, Shareable, Emitter, Scattering, Sensor

public class Camera
extends CameraBase
implements Shareable, Manageable, Sensor


Nested Class Summary
static class Camera.Type
           
 
Field Summary
static Camera.Type $TYPE
           
protected  float maxZ
           
static SCOType.Field maxZ$FIELD
           
protected  float minZ
           
static SCOType.Field minZ$FIELD
           
protected  Projection projection
           
static SCOType.Field projection$FIELD
           
protected  SharedObjectProvider sop
           
protected  Matrix4d transformation
           
static SCOType.Field transformation$FIELD
           
 
Fields inherited from interface de.grogra.ray.physics.Scattering
DELTA_FACTOR, IS_NON_OPAQUE, MIN_UNUSED_FLAG, NEEDS_NORMAL, NEEDS_POINT, NEEDS_TANGENTS, NEEDS_TRANSFORMATION, NEEDS_UV, RANDOM_RAYS_GENERATE_ORIGINS
 
Constructor Summary
Camera()
           
Camera(Projection p)
           
 
Method Summary
 void addReference(SharedObjectReference ref)
           
 void appendReferencesTo(java.util.List out)
           
 double completeRay(Environment env, Point3d vertex, Ray out)
           
 float computeBSDF(Environment env, Vector3f in, Spectrum specIn, Vector3f out, boolean adjoint, Spectrum bsdf)
          Evaluates bidirectional scattering distribution function for given input.
 double computeExitance(Environment env, Spectrum exitance)
          Evaluates the exitance function for given input.
static Camera createBackView()
           
static Camera createBottomView()
           
static Camera createFrontView()
           
static Camera createLeftView()
           
static Camera createParallel()
           
static Camera createPerspective()
           
static Camera createRightView()
           
static Camera createTopView()
           
 void fieldModified(PersistenceField field, int[] indices, Transaction t)
           
 void generateRandomOrigins(Environment env, RayList out, java.util.Random rnd)
          Pseudorandomly generates, for the given input, a set of origins for this emitter.
 void generateRandomRays(Environment env, Vector3f out, Spectrum specOut, RayList rays, boolean adjoint, java.util.Random rnd)
          Pseudorandomly generates, for the given input, a set of scattered rays.
 int getAverageColor()
          Returns an average color for the scattering entity.
 int getFlags()
           
 ManageableType getManageableType()
           
 Projection getProjection()
           
 SharedObjectProvider getProvider()
           
 void getRay(float x, float y, Point3d origin, Vector3d direction)
          Determines the ray which starts at the camera and goes through the specified point on the image plane of the camera.
 float getScaleAt(double x, double y, double z)
          Computes an estimate for the scaling factor from 3D world coordinates at (x, y, z) to 2D coordinates on the camera plane.
 float getScaleAt(float z)
          Computes an estimate for the scaling factor from view coordinates around a depth of z to 2D coordinates on the camera plane.
 int getStamp()
          Returns a stamp for this object.
 Matrix4d getTransformation()
           
 float[] getUVForVertex(Environment env, Point3d vertex)
           
 void getViewToClipTransformation(Matrix4d m)
          Computes the transformation from view coordinates (= camera coordinates, not world coordinates!)
 Matrix4d getWorldToViewTransformation()
          Returns the world-to-view transformation of this camera.
 float getZFar()
           
 float getZNear()
           
 void initProvider(SharedObjectProvider provider)
           
 Manageable manageableReadResolve()
           
 java.lang.Object manageableWriteReplace()
           
 boolean projectView(float px, float py, float pz, Tuple2f point2D, boolean checkClip)
           
 boolean projectWorld(double px, double py, double pz, Tuple2f point2D)
           
 void removeReference(SharedObjectReference ref)
           
 void setProjection(Projection value)
           
 void setTransformation(Matrix4d value)
           
 void setZFar(float maxZ)
           
 void setZNear(float minZ)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

$TYPE

public static final Camera.Type $TYPE

maxZ

protected float maxZ

maxZ$FIELD

public static final SCOType.Field maxZ$FIELD

minZ

protected float minZ

minZ$FIELD

public static final SCOType.Field minZ$FIELD

projection

protected Projection projection

projection$FIELD

public static final SCOType.Field projection$FIELD

sop

protected transient SharedObjectProvider sop

transformation

protected final Matrix4d transformation

transformation$FIELD

public static final SCOType.Field transformation$FIELD
Constructor Detail

Camera

public Camera()

Camera

public Camera(Projection p)
Method Detail

addReference

public void addReference(SharedObjectReference ref)
Specified by:
addReference in interface Shareable

appendReferencesTo

public void appendReferencesTo(java.util.List out)
Specified by:
appendReferencesTo in interface Shareable

completeRay

public double completeRay(Environment env,
                          Point3d vertex,
                          Ray out)
Specified by:
completeRay in interface Emitter

computeBSDF

public float computeBSDF(Environment env,
                         Vector3f in,
                         Spectrum specIn,
                         Vector3f out,
                         boolean adjoint,
                         Spectrum bsdf)
Description copied from interface: Scattering
Evaluates bidirectional scattering distribution function for given input.

The computed spectrum is an integral over the spectrum of the following product:

|cos θ| BSDF(ωi, νi; ωo, νo)
where BSDF is the bidirectional scattering distribution function (= BRDF + BTDF) at the point env.point, ωi the (negated) direction of the incoming light ray, νi the frequency where the incoming ray is sampled, ωo the direction of the outgoing light ray, νo the frequency where the outgoing ray is sampled, and θ the angle between the surface normal and out.

If adjoint is false, in and out describe true light rays from light sources to sensors. In this case, ωi = in, ωo = out, and the integral is

bsdf(ν) = |cos θ| ∫ BSDF(in, νi; out, ν) specIni) dνi
Otherwise, adjoint is true. in and out then describe importance rays (inverse light rays from sensors to light sources). In this case, ωi = out, ωo = in, and the integral is
bsdf(ν) = |cos θ| ∫ BSDF(out, ν; in, νo) specIno) dνo

If this Scattering instance is in fact a Light source, adjoint is false, and the BSDF is defined as BSDF(in, μ; ω, ν) = L1(ω, ν) δ(μ - ν), i.e., the directional distribution of the emitted radiance at env.point, see Emitter. In this case, in is not used.

If this Scattering instance is in fact a Sensor, adjoint is true, and the BSDF is defined as BSDF(ω, ν; in, μ) = W1(ω, ν) δ(μ - ν), i.e., the directional distribution of the emitted importance at env.point, see Emitter. In this case, in is not used.

The computation should be physically valid. This excludes, e.g., ambient or emissive light contributions.

The returned value is the value of the probability density pω that would be calculated by Scattering.generateRandomRays(de.grogra.ray.physics.Environment, javax.vecmath.Vector3f, de.grogra.ray.physics.Spectrum, de.grogra.ray.util.RayList, boolean, java.util.Random) if the ray happened to be one of the randomly generated rays.

Specified by:
computeBSDF in interface Scattering
Parameters:
env - the environment for scattering
in - the (negated) direction unit vector of the incoming ray (i.e., pointing away from the surface)
specIn - the spectrum of the incoming ray
out - the direction unit vector of the outgoing ray (i.e., pointing away from the surface)
adjoint - light ray or importance ray?
bsdf - the computed spectrum of the outgoing ray will be placed in here
Returns:
the value of the probability density for the ray direction

computeExitance

public double computeExitance(Environment env,
                              Spectrum exitance)
Description copied from interface: Emitter
Evaluates the exitance function for given input. The computed value is the spectrum of the radiant exitance (emitted power per area) L0j(x, ν) at the point env.point in case of light sources, or the corresponding function W0j(x, ν) in case of sensors.

The returned value is the value of the probability density px that would be calculated by Emitter.generateRandomOrigins(de.grogra.ray.physics.Environment, de.grogra.ray.util.RayList, java.util.Random) if env.point happened to be one of the randomly generated origins.

Specified by:
computeExitance in interface Emitter
Parameters:
env - the environment for scattering
exitance - the exitance values will be placed in here
Returns:
the value of the probability density for the ray origin

createBackView

public static Camera createBackView()

createBottomView

public static Camera createBottomView()

createFrontView

public static Camera createFrontView()

createLeftView

public static Camera createLeftView()

createParallel

public static Camera createParallel()

createPerspective

public static Camera createPerspective()

createRightView

public static Camera createRightView()

createTopView

public static Camera createTopView()

fieldModified

public void fieldModified(PersistenceField field,
                          int[] indices,
                          Transaction t)
Specified by:
fieldModified in interface Manageable

generateRandomOrigins

public void generateRandomOrigins(Environment env,
                                  RayList out,
                                  java.util.Random rnd)
Description copied from interface: Emitter
Pseudorandomly generates, for the given input, a set of origins for this emitter. They are generated such that they can be used for Monte Carlo-based photon tracing algorithms in the following way.

At first, we consider the case where the emitter is in fact a light source. Let L(x, ω, ν) be the emitted spectral radiance for the frequency ν at the light's surface point x in direction ω. The radiant exitance (emitted spectral power per area) at x is defined as

L0(x, ν) = ∫ cos θ L(x, ω, ν) dω
where θ is the angle between the surface normal and ω. Now the directional distribution of the emitted radiance at x can be described by the density
L1(x, ω, ν) = L(x, ω, ν) / L0(x, ν)
so that the radiance is split into
L(x, ω, ν) = L0(x, ν) L1(x, ω, ν)
Let oi and si denote the origins and spectra of the N generated rays (N = rays.size). Then for a function f(x, ν) which is to be integrated over the light surface, the sum
1 / N ∑i si(ν) f(oi, ν)
is an unbiased estimate for the integral
∫ L0(x, ν) f(x, ν) dA
The integral ranges over the whole surface A of the light source. As a consequence, the spectrum of a ray is to be considered as the ray's radiant spectral power.

Now if the emitter is a sensor, let W(x, ω, ν) be the emitted spectral importance for frequency ν at the sensors's surface point x in direction ω. The quantities W0(x, ν) and W1(x, ω, ν) are defined similarly to the case of light sources:

W0(x, ν) = ∫ cos θ W(x, ω, ν) dω
W(x, ω, ν) = W0(x) W1(x, ω, ν)
The formulas for light sources are valid for sensors if the L-quantites are replaced by the corresponding W-quantities.

Let px be the probability density used for the ray origin, then the field originDensity is set to px(oi) for each ray. For emitters which are concentrated at a single point (e.g., point lights) px is not a regular function, the value originDensity will be set to a multiple of Scattering.DELTA_FACTOR.

The ray properties which are not mentioned in the given formulas are neither used nor modified. These are the direction and its density.

Specified by:
generateRandomOrigins in interface Emitter
Parameters:
env - the environment
out - the outgoing rays to be generated
rnd - pseudorandom generator

generateRandomRays

public void generateRandomRays(Environment env,
                               Vector3f out,
                               Spectrum specOut,
                               RayList rays,
                               boolean adjoint,
                               java.util.Random rnd)
Description copied from interface: Scattering
Pseudorandomly generates, for the given input, a set of scattered rays. The scattered rays are generated such that they can be used for a Monte Carlo integration of a function f(ω;ν) over cos θ BSDF(ωi, νi; ωo, νo) in the following way: Let di and si denote the directions and spectra of the N generated rays (N = rays.size). Then, for every frequency ν the sum
1 / N ∑i si(ν) f(di; ν)
is an unbiased estimate for the integral
∫ cos θ f(ω; ν) g(ω, ν; out, μ) specOut(μ) dμ dω
θ is the angle between the surface normal and ω. The domain of integration is the whole sphere, since the bidirectional scattering distribution includes both reflection and transmission (BSDF = BRDF + BTDF).

If this Scattering instance is in fact a Light source, adjoint is true, and the BSDF is defined as BSDF(out, μ; ω, ν) = L1(ω, ν) δ(μ - ν), i.e., the directional distribution of the emitted radiance at env.point, see Emitter. In this case, out is not used.

If this Scattering instance is in fact a Sensor, adjoint is false, and the BSDF is defined as BSDF(ω, ν; out, μ) = W1(ω, ν) δ(μ - ν), i.e., the directional distribution of the emitted importance at env.point, see Emitter. In this case, out is not used.

Let pω be the probability density used for the ray direction (measured with respect to solid angle ω), then the field directionDensity of the ray i is set to pω(di). For ideal specular reflection or transmission, or for directional lights or sensors, pω is not a regular function, the value directionDensity will be set to a multiple of Scattering.DELTA_FACTOR.

The ray properties which are not mentioned in the given formulas are neither used nor modified. These are the origin and its density.

Specified by:
generateRandomRays in interface Scattering
Parameters:
env - the environment for scattering
out - the direction unit vector of the outgoing ray (i.e., pointing away from the surface)
specOut - the spectrum of the outgoing ray
rays - the rays to be generated
adjoint - represents out a light ray or an importance ray?
rnd - pseudorandom generator
See Also:
Scattering.computeBSDF(de.grogra.ray.physics.Environment, javax.vecmath.Vector3f, de.grogra.ray.physics.Spectrum, javax.vecmath.Vector3f, boolean, de.grogra.ray.physics.Spectrum)

getAverageColor

public int getAverageColor()
Description copied from interface: Scattering
Returns an average color for the scattering entity. This color is used for simplified graphical representations of the corresponding objects.

Specified by:
getAverageColor in interface Scattering
Returns:
an average color in Java's default sRGB color space, encoded as an int (0xAARRGGBB).

getFlags

public int getFlags()
Specified by:
getFlags in interface Scattering

getManageableType

public ManageableType getManageableType()
Specified by:
getManageableType in interface Manageable

getProjection

public Projection getProjection()

getProvider

public SharedObjectProvider getProvider()
Specified by:
getProvider in interface Shareable

getRay

public void getRay(float x,
                   float y,
                   Point3d origin,
                   Vector3d direction)
Description copied from class: CameraBase
Determines the ray which starts at the camera and goes through the specified point on the image plane of the camera.

Specified by:
getRay in class CameraBase
Parameters:
x - the x-coordinate on the image plane
y - the y-coordinate on the image plane
origin - the origin of the ray, in world coordinates
direction - the direction of the ray, in world coordinates

getScaleAt

public float getScaleAt(double x,
                        double y,
                        double z)
Description copied from class: CameraBase
Computes an estimate for the scaling factor from 3D world coordinates at (x, y, z) to 2D coordinates on the camera plane.

Specified by:
getScaleAt in class CameraBase
Parameters:
x - x world coordinate
y - y world coordinate
z - z world coordinate
Returns:
scaling factor of camera projection at location

getScaleAt

public float getScaleAt(float z)
Description copied from class: CameraBase
Computes an estimate for the scaling factor from view coordinates around a depth of z to 2D coordinates on the camera plane.

Specified by:
getScaleAt in class CameraBase
Parameters:
z - z view coordinate
Returns:
scaling factor of camera projection at location

getStamp

public int getStamp()
Description copied from interface: Manageable
Returns a stamp for this object. Each modification to this object increments the stamp. The initial stamp is non-negative.

Specified by:
getStamp in interface Manageable
Returns:
a stamp

getTransformation

public Matrix4d getTransformation()

getUVForVertex

public float[] getUVForVertex(Environment env,
                              Point3d vertex)
Specified by:
getUVForVertex in interface Sensor

getViewToClipTransformation

public void getViewToClipTransformation(Matrix4d m)
Computes the transformation from view coordinates (= camera coordinates, not world coordinates!) to clip coordinates.

Parameters:
m - the transformation is placed in here

getWorldToViewTransformation

public Matrix4d getWorldToViewTransformation()
Description copied from class: CameraBase
Returns the world-to-view transformation of this camera. It transforms world coordinates to view coordinates (= camera coordinates).

Specified by:
getWorldToViewTransformation in class CameraBase
Returns:
world-to-view transformation

getZFar

public float getZFar()
Specified by:
getZFar in class CameraBase

getZNear

public float getZNear()
Specified by:
getZNear in class CameraBase

initProvider

public void initProvider(SharedObjectProvider provider)
Specified by:
initProvider in interface Shareable

manageableReadResolve

public Manageable manageableReadResolve()
Specified by:
manageableReadResolve in interface Manageable

manageableWriteReplace

public java.lang.Object manageableWriteReplace()
Specified by:
manageableWriteReplace in interface Manageable

projectView

public boolean projectView(float px,
                           float py,
                           float pz,
                           Tuple2f point2D,
                           boolean checkClip)

projectWorld

public boolean projectWorld(double px,
                            double py,
                            double pz,
                            Tuple2f point2D)

removeReference

public void removeReference(SharedObjectReference ref)
Specified by:
removeReference in interface Shareable

setProjection

public void setProjection(Projection value)

setTransformation

public void setTransformation(Matrix4d value)

setZFar

public void setZFar(float maxZ)

setZNear

public void setZNear(float minZ)