EnvMap.fx File Reference

Defines
#define	CUBEMAP_SIZE   128
	size of the cube map taken from the reference point of the object
#define	LR_CUBEMAP_SIZE   4
	size of the cube map for diffuse/glossy reflections
#define	RATE   (CUBEMAP_SIZE/LR_CUBEMAP_SIZE)
	cube map downsampling rate for diffuse/glossy reflections
#define	PI   3.14159f
#define	TechniqueUsingCommonVS(name)
	a helpful macro to define techniques with a common vertex program
#define	Technique(name)
	a helpful macro to define techniques
Functions
ReduceTextureVS_output	ReduceTextureVS (ReduceTextureVS_input IN)
	See the pixel program.
float4	ReduceTexturePS (ReduceTextureVS_output IN)
	Downsamples a face of a cube map.
float4	GetContibution (float3 q, float3 L)
	Returns the precalculated contribution of a texel with regard to the specified query direction.
ConvolutionVS_output	ConvolutionVS (ConvolutionVS_input IN)
	See the pixel program.
float4	ConvolutionPS (ConvolutionVS_output IN)
	Convolves the values of a cube map.
float3	Hit (float3 x, float3 R, sampler mp)
	This function approximately traces a ray from point x towards direction R. Depth information is obtained from the alpha channel of mp.
float4	metal_reflectivity (float3 L, float3 N, float3 V)
	Simple Fresnel term approximation for metals.
EnvMapVS_output	EnvMapVS (EnvMapVS_input IN)
float4	EnvMapImpostorPS (EnvMapVS_output IN)
	Environment mapping with distance impostors.
float4	EnvMapImpostorMetalPS (EnvMapVS_output IN)
float4	EnvMapClassicPS (EnvMapVS_output IN)
	Classic environment mapping technique.
float4	EnvMapClassicMetalPS (EnvMapVS_output IN)
	Classic environment mapping technique with a simple Fresnel term approximation (metal_reflectivity()).
float4	EnvMapDiffusePS (EnvMapVS_output IN)
	Determines diffuse or specular illumination with a single lookup into PreconvolvedEnvironmentMap.
float4	GetContibution (float3 L, float3 pos, float3 N, float3 V)
	Calculates the contribution of a single texel of SmallEnvironmentMap to the illumination of the shaded point.
float4	EnvMapDiffuseLocalizedPS (EnvMapVS_output IN)
	Calculates diffuse or specular contributions of all texels in SmallEnvironmentMap to the current point. For each texel of SmallEnvironmentMap, function GetContibution(float3,float3,float3,float3) is called.
float4	GetContibutionWithCosLookup (float3 L, float3 pos, float3 N, float3 V)
	Calculates the contribution of a single texel of SmallEnvironmentMap to the illumination of the shaded point.
float4	EnvMapDiffuseLocalizedWithCosLookupPS (EnvMapVS_output IN)
	Calculates diffuse or specular contributions of all texels in SmallEnvironmentMap to the current point. For each texel of SmallEnvironmentMap, function GetContibutionWithCosLookup() is called.
IlluminatedSceneVS_output	IlluminatedSceneVS (IlluminatedSceneVS_input IN)
float4	IlluminatedScenePS (IlluminatedSceneVS_output IN)
	Displays the environment with a simple shading.
	TechniqueUsingCommonVS (EnvMapClassic)
	TechniqueUsingCommonVS (EnvMapImpostor)
	TechniqueUsingCommonVS (EnvMapDiffuse)
	Technique (IlluminatedScene)
	Technique (ReduceTexture)
	Technique (Convolution)
Variables
float4x4	World
	World matrix for the current object.
float4x4	WorldIT
	World matrix IT (inverse transposed) to transform surface normals of the current object.
float4x4	WorldView
	World * View matrix.
float4x4	WorldViewProjection
	World * View * Projection matrix.
float	texel_size
	upload this constant every time the viewport changes
float4	eyePos
	current eye (camera) position
float4	reference_pos
	Reference point for the last cube map generation.
int	nFace
int	iShowCubeMap
float4	objColor
float3	nMetal
	real part of the refraction coefficient for metals
float3	kMetal
	imaginary part of the refraction coefficient for metals
float	sFresnel
	Fresnel refraction param.
float	refractionIndex
float	intensity
float	shininess
float	brightness
texture	EnvironmentMap
texture	SmallEnvironmentMap
texture	PreconvolvedEnvironmentMap
texture	Decoration
sampler	EnvironmentMapSampler
sampler	PreconvolvedEnvironmentMapSampler
sampler	SmallEnvironmentMapSampler
sampler	DecorationSampler

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Define Documentation

#define CUBEMAP_SIZE   128

size of the cube map taken from the reference point of the object

#define LR_CUBEMAP_SIZE   4

size of the cube map for diffuse/glossy reflections

#define PI   3.14159f

#define RATE   (CUBEMAP_SIZE/LR_CUBEMAP_SIZE)

cube map downsampling rate for diffuse/glossy reflections

#define Technique (  name   )

Value: ; \ technique name \ { \ pass p0 \ { \ VertexShader = compile vs_3_0 name##VS(); \ PixelShader = compile ps_3_0 name##PS(); \ } \ } a helpful macro to define techniques

#define TechniqueUsingCommonVS (  name   )

Value: ; \ technique name \ { \ pass p0 \ { \ VertexShader = compile vs_3_0 EnvMapVS(); \ PixelShader = compile ps_3_0 name##PS(); \ } \ } a helpful macro to define techniques with a common vertex program

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Function Documentation

float4 ConvolutionPS (  ConvolutionVS_output  IN  )

Convolves the values of a cube map. Calculates the diffuse/specular irradiance map of resolution LR_CUBEMAP_SIZE by summing up the contributions of all cube map texels with regard to the current query direction. Parameters: SmallEnvironmentMap  is bound to EnvMap::pCubeTextureSmall (cube map of resolution LR_CUBEMAP_SIZE)

ConvolutionVS_output ConvolutionVS (  ConvolutionVS_input  IN  )

See the pixel program.

float4 EnvMapClassicMetalPS (  EnvMapVS_output  IN  )

Classic environment mapping technique with a simple Fresnel term approximation (metal_reflectivity()).

float4 EnvMapClassicPS (  EnvMapVS_output  IN  )

Classic environment mapping technique. Simply determines the ideal reflection/refraction direction and performs a cube map lookup into that direction Parameters: EnvironmentMap  is bound to EnvMap::pCubeTexture (cube map of resolution CUBEMAP_SIZE)

float4 EnvMapDiffuseLocalizedPS (  EnvMapVS_output  IN  )

Calculates diffuse or specular contributions of all texels in SmallEnvironmentMap to the current point. For each texel of SmallEnvironmentMap, function GetContibution(float3,float3,float3,float3) is called. Parameters: SmallEnvironmentMap  is bound to EnvMap::pCubeTextureSmall (cube map of resolution LR_CUBEMAP_SIZE)

float4 EnvMapDiffuseLocalizedWithCosLookupPS (  EnvMapVS_output  IN  )

Calculates diffuse or specular contributions of all texels in SmallEnvironmentMap to the current point. For each texel of SmallEnvironmentMap, function GetContibutionWithCosLookup() is called. Parameters: SmallEnvironmentMap  is bound to EnvMap::pCubeTextureSmall (cube map of resolution LR_CUBEMAP_SIZE)

float4 EnvMapDiffusePS (  EnvMapVS_output  IN  )

Determines diffuse or specular illumination with a single lookup into PreconvolvedEnvironmentMap. Parameters: PreconvolvedEnvironmentMap  is bound to EnvMap::pCubeTexturePreConvolved (cube map of resolution LR_CUBEMAP_SIZE)

float4 EnvMapImpostorMetalPS (  EnvMapVS_output  IN  )

float4 EnvMapImpostorPS (  EnvMapVS_output  IN  )

Environment mapping with distance impostors. Determines the ideal reflection/refraction direction and approximately traces a ray toward that direction using the Hit() function. Parameters: EnvironmentMap  is bound to EnvMap::pCubeTexture (cube map of resolution CUBEMAP_SIZE)

EnvMapVS_output EnvMapVS (  EnvMapVS_input  IN  )

float4 GetContibution (  float3  L, float3  pos, float3  N, float3  V )

Calculates the contribution of a single texel of SmallEnvironmentMap to the illumination of the shaded point. Parameters: L  vector pointing to the center of the texel under examination. We assume that the largest coordinate component of L is equal to one, i.e. L points to the face of a cube of edge length of 2. pos  is the position of the shaded point N  is the surface normal at the shaded point V  is the viewing direction at the shaded point

float4 GetContibution (  float3  q, float3  L )

Returns the precalculated contribution of a texel with regard to the specified query direction. Parameters: q  query direction (i.e. surface normal in diffuse case, ideal reflection direction in specular case). L  vector pointing to the texel center

float4 GetContibutionWithCosLookup (  float3  L, float3  pos, float3  N, float3  V )

Calculates the contribution of a single texel of SmallEnvironmentMap to the illumination of the shaded point. The only difference from GetContibution(float3,float3,float3,float3) is that now we use precalculated integral values to compute reflectivity (instead of using only one sample).

float3 Hit (  float3  x, float3  R, sampler  mp )

This function approximately traces a ray from point x towards direction R. Depth information is obtained from the alpha channel of mp. Returns: the approximate hit point.

float4 IlluminatedScenePS (  IlluminatedSceneVS_output  IN  )

Displays the environment with a simple shading.

IlluminatedSceneVS_output IlluminatedSceneVS (  IlluminatedSceneVS_input  IN  )

float4 metal_reflectivity (  float3  L, float3  N, float3  V )

Simple Fresnel term approximation for metals. The metal is described by its (complex) refraction coefficient (nMetal,kMetal).

float4 ReduceTexturePS (  ReduceTextureVS_output  IN  )

Downsamples a face of a cube map. Downsamples the nFace-th face of a cube map from resolution CUBEMAP_SIZE to LR_CUBEMAP_SIZE by averaging the corresponding texel values. The EnvironmentMap is sampled via EnvironmentMapSampler. Parameters: nFace  uniform parameter identifies the current face (0...5)

ReduceTextureVS_output ReduceTextureVS (  ReduceTextureVS_input  IN  )

See the pixel program.

Technique (  Convolution   )

Technique (  ReduceTexture   )

Technique (  IlluminatedScene   )

TechniqueUsingCommonVS (  EnvMapDiffuse   )

TechniqueUsingCommonVS (  EnvMapImpostor   )

TechniqueUsingCommonVS (  EnvMapClassic   )

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Variable Documentation

float brightness

texture Decoration

sampler DecorationSampler

Initial value: sampler_state { Texture = <Decoration>; MinFilter = LINEAR; MagFilter = LINEAR; AddressU = CLAMP; AddressV = CLAMP; }

texture EnvironmentMap

sampler EnvironmentMapSampler

Initial value: sampler_state { Texture = <EnvironmentMap>; AddressU = WRAP; AddressV = WRAP; }

float4 eyePos

current eye (camera) position

float intensity

int iShowCubeMap

float3 kMetal

imaginary part of the refraction coefficient for metals

int nFace

float3 nMetal

real part of the refraction coefficient for metals

float4 objColor

texture PreconvolvedEnvironmentMap

sampler PreconvolvedEnvironmentMapSampler

Initial value: sampler_state { MinFilter = LINEAR; MagFilter = LINEAR; Texture = <PreconvolvedEnvironmentMap>; AddressU = WRAP; AddressV = WRAP; }

float4 reference_pos

Reference point for the last cube map generation.

float refractionIndex

float sFresnel

Fresnel refraction param.

float shininess

texture SmallEnvironmentMap

sampler SmallEnvironmentMapSampler

Initial value: sampler_state { MinFilter = Point; MagFilter = Point; Texture = <SmallEnvironmentMap>; AddressU = WRAP; AddressV = WRAP; }

float texel_size

upload this constant every time the viewport changes

float4x4 World

World matrix for the current object.

float4x4 WorldIT

World matrix IT (inverse transposed) to transform surface normals of the current object.

float4x4 WorldView

World * View matrix.

float4x4 WorldViewProjection

World * View * Projection matrix.

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