BRDF Class Reference

#include <BRDF.h>

Inheritance diagram for BRDF:

List of all members.

Public Types
enum	RetVal {   NONZERO_CONTRIB = 1, BAD_PARAMS = 2, NL_NEGATIVE = 3, NV_NEGATIVE = 4,   NL_OR_NV_NEGATIVE = 5, ZERO_CONTRIB = 6 }
Public Member Functions
	_isIsotropic (isotropic)
virtual	~BRDF ()
bool	diffuse (void) const
bool	specular (void) const
bool	isotropic (void) const
bool	anisotropic (void) const
virtual RetVal	reflectance (const MatVisitor &visitor, const Vector3 *L, const Vector3 *V, const Vector3 *N, Vector3 &color)=0
virtual RetVal	reflectanceVNL (const MatVisitor &visitor, const Vector3 *L, const Vector3 *V, const Vector3 *N, double NV, double NL, Vector3 &color)=0
virtual RetVal	reflectanceNL (const MatVisitor &visitor, const Vector3 *L, const Vector3 *V, const Vector3 *N, double NL, Vector3 &color)=0
virtual BRDF *	clone () const =0
virtual double	albedo (const MatVisitor &visitor, const Vector3 &N, const Vector3 *V) const =0
virtual void	importanceSample (const MatVisitor &visitor, const Vector3 &D, double r1, double r2, Vector3 &dir, double *pPDFVal)=0
virtual Vector2	dir2uv (const MatVisitor &visitor, const Vector3 &N, const Vector3 &D) const =0
Public Attributes
	__pad0__: _isDiffuse(diffuse)
Protected Member Functions
virtual void	_duplicate_attributes (const BRDF &src)
Protected Attributes
bool	_isDiffuse
bool	_isIsotropic

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Detailed Description

Bidirectional Reflectance Distribution Functions

Definition at line 17 of file BRDF.h.

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Member Enumeration Documentation

enum RetVal

Informations about reflectance Enumerator: NONZERO_CONTRIB  color is set (including black) BAD_PARAMS  unable to compute reflectance NL_NEGATIVE  dot-product of normal, N, and light direction, L, is less than zero NV_NEGATIVE  dot-product of normal, N, and viewer direction, V, is less than zero NL_OR_NV_NEGATIVE  either N*L or N*V is less than zero ZERO_CONTRIB  no energy is reflected in given direction Definition at line 22 of file BRDF.h.

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Constructor & Destructor Documentation

virtual ~BRDF (   )  [inline, virtual]

Destructor Definition at line 56 of file BRDF.h.

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Member Function Documentation

virtual void _duplicate_attributes (  const BRDF &  src  )  [inline, protected, virtual]

Reimplemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF. Definition at line 36 of file BRDF.h. References BRDF::_isDiffuse, and BRDF::_isIsotropic. Referenced by SpecularBRDF::_duplicate_attributes(), and DiffuseBRDF::_duplicate_attributes().

_isIsotropic (  isotropic   )  [inline]

Definition at line 51 of file BRDF.h.

virtual double albedo (  const MatVisitor &  visitor, const Vector3 &  N, const Vector3 *  V )  const [pure virtual]

Albedo for importance sampling strategies. Parameters: visitor  visitor of material coefficients N  normalized normal vector V  normalized direction to viewer Returns: albedo Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

bool anisotropic (  void   )  const [inline]

Returns: true if BRDF is anisotropic (reflectance dependents on rotation around normal), false otherwise Definition at line 80 of file BRDF.h.

virtual BRDF* clone (   )  const [pure virtual]

Duplicates the BRDF Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

bool diffuse (  void   )  const [inline]

Returns: true if BRDF is diffuse, false otherwise Definition at line 61 of file BRDF.h.

virtual Vector2 dir2uv (  const MatVisitor &  visitor, const Vector3 &  N, const Vector3 &  D )  const [pure virtual]

Gets direction in global coords and returns its generating "random" numbers (i.e. the inverse function to importanceSample()) Parameters: visitor  visitor of material coefficients N  normalized normal vector D  normalized direction Returns: "random" numbers generating direction D; x item of returned vector corresponds to r1 of importanceSample() method, y item corresponds to r2 Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

virtual void importanceSample (  const MatVisitor &  visitor, const Vector3 &  D, double  r1, double  r2, Vector3 &  dir, double *  pPDFVal )  [pure virtual]

Point sampling interface - importance sampling. This method gets two random numbers and preffered direction of random sample and selects amd returns random direction. Energy contribution gained from such random directions should be laer devided by average spectral reflectance (e.g. visitor.avgDiffuse() or visitor.avgSpecular()) in order to account for the fact that the reflectance should have used different values for individual spectrums (e.g. RGB) Parameters: visitor  visitor of material coefficients D  normalized vector determining prefered direction of the sample r1  random number from the range [0,1) r2  random number from the range [0,1) dir  random direction selected by this method pPDFVal  corresponding PDF value Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

bool isotropic (  void   )  const [inline]

Returns: true if BRDF is isotropic (reflectance is independent of rotation around normal), false otherwise Definition at line 73 of file BRDF.h.

virtual RetVal reflectance (  const MatVisitor &  visitor, const Vector3 *  L, const Vector3 *  V, const Vector3 *  N, Vector3 &  color )  [pure virtual]

Computes and returns actual reflectance. Parameters: visitor  visitor of material coefficients L  normalized direction to light source V  normalized direction to viewer N  normalized normal vector color  computed reflected energy (color) Returns: additionnal informations about reflected energy Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

virtual RetVal reflectanceNL (  const MatVisitor &  visitor, const Vector3 *  L, const Vector3 *  V, const Vector3 *  N, double  NL, Vector3 &  color )  [pure virtual]

Computes and returns actual reflectance. This variant speeds up the computation using given precomputed dot-product of N and L Parameters: visitor  visitor of material coefficients L  normalized direction to light source V  normalized direction to viewer N  normalized normal vector NL  precomputed dot-product of normal N and L color  computed reflected energy (color) Returns: additionnal informations about reflected energy Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

virtual RetVal reflectanceVNL (  const MatVisitor &  visitor, const Vector3 *  L, const Vector3 *  V, const Vector3 *  N, double  NV, double  NL, Vector3 &  color )  [pure virtual]

Computes and returns actual reflectance. This variant speeds up the computation using given precomputed dot-products of N, V and L Parameters: visitor  visitor of material coefficients L  normalized direction to light source V  normalized direction to viewer N  normalized normal vector NV  precomputed dot-product of normal N and V NL  precomputed dot-product of normal N and L color  computed reflected energy (color) Returns: additionnal informations about reflected energy Implemented in BlinnBRDF, CookTorranceBRDF, DiffuseBRDF, LambertianBRDF, PhongBRDF, and SpecularBRDF.

bool specular (  void   )  const [inline]

Returns: true if BRDF is specular, false otherwise Definition at line 66 of file BRDF.h.

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Member Data Documentation

__pad0__

Contructor Parameters: diffuse  determines whether this BRDF is diffuse (reflectance is independent of viewer direction) isotropic  determines whether this BRDF is isotropic (reflectance is independent of rotation around normal) Definition at line 51 of file BRDF.h.

bool _isDiffuse [protected]

Definition at line 32 of file BRDF.h. Referenced by BRDF::_duplicate_attributes().

bool _isIsotropic [protected]

Definition at line 33 of file BRDF.h. Referenced by BRDF::_duplicate_attributes().

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The documentation for this class was generated from the following file:

• esg/include/esg/brdf/BRDF.h

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