ShaderHelper< ShaderParameters > Class Template Reference

#include <adskShader.h>

List of all members.

---

Detailed Description

template<typename ShaderParameters>
class ShaderHelper< ShaderParameters >

Shader helper class.

This class has several methods which can be used to override the default shading behaviour.

Template Parameters:

ShaderParameters

The shader parameter structure.

Public Member Functions
	ShaderHelper (miState *pState, ShaderParameters *pParameters)
	Constructor for shader helper.
	~ShaderHelper ()
	Deconstructor for shader helper.
void	setupMayaBumpMapping () const
	Adjust normal for Maya's bump mapping.
miBoolean	computeHideSource () const
	Determine if source should be hidden.
void	computeTransparencyForShadow (miColor &pResTransp, miBoolean pHideSource) const
	Computes transparency for shadow rays.
void	evaluateParameters ()
	Evaluates shader parameters necessary for later computations.
miColor	computeTransparency () const
	Computes transparency parameters for non-shadow rays.
miScalar	computeSpecularGlow () const
	Computes the specular glow parameters for the shader.
void	setASQWeight (MayabaseState *&MBS, BRDFComponent &bc, const miColor &pColor, const miColor &pTransparency, miScalar &pGlowIntensity) const
	Set the ASQ weight for this shader call.
miColor	computeAmbientResult (const miColor &pAmbientColor, const miColor &pColor) const
	Computes the ambient result color.
miScalar	computeTranslucence (miScalar pDotNL, miVector &pLightDirection, miScalar pTranslucence, miScalar pTranslucenceFocus, miScalar pTranslucenceDepth, void *pLightBlindData) const
	Computes the translucence result for the shader.
float	computeDiffuseAreaLightFactor (miVector &pBumpNormal, void *pLightBlindData) const
	Computes the diffuse factor for area lights.
float	computeSpecularAreaLightFactor (miVector &pBumpNormal, void *pLightBlindData) const
	Computes the specular factor for area lights.
miColor	getReflectedColor () const
	Return the reflected color for this shader.

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Constructor & Destructor Documentation

template<typename ShaderParameters>

ShaderHelper< ShaderParameters >::ShaderHelper	(	miState *	pState,
		ShaderParameters *	pParameters
	)			[inline]

Constructor for shader helper.

This will be called once per evaluation of the main shading function for the shader.

Parameters:

[in,out]	pState	A pointer to the mental ray state structure.
[in]	pParameters	A pointer to the shader parameters.

template<typename ShaderParameters>

ShaderHelper< ShaderParameters >::~ShaderHelper

(

)

[inline]

Deconstructor for shader helper.

This will be called once per evaluation of the main shading function for the shader.

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Member Function Documentation

template<typename ShaderParameters>

void ShaderHelper< ShaderParameters >::setupMayaBumpMapping

(

)

const [inline]

Adjust normal for Maya's bump mapping.

This function adjusts state->normal to account for bump mapping. Override it to change how bump mapping works.

template<typename ShaderParameters>

miBoolean ShaderHelper< ShaderParameters >::computeHideSource

(

)

const [inline]

Determine if source should be hidden.

Most Maya shaders define the hideSource attribute to determine if the source geometry should be hidden (often used with glow). Override this to tell the main shading function whether or not the source should be hidden.

Returns:

True if source should be hidden, false otherwise.

template<typename ShaderParameters>

void ShaderHelper< ShaderParameters >::computeTransparencyForShadow	(	miColor &	pResTransp,
		miBoolean	pHideSource
	)			const [inline]

Computes transparency for shadow rays.

This function computes the transparency of the shader when hit by a shadow ray.

Parameters:

[out]	pResTransp	The resulting transparency.
[in]	pHideSource	True if the source is hidden.

template<typename ShaderParameters>

void ShaderHelper< ShaderParameters >::evaluateParameters

(

)

[inline]

Evaluates shader parameters necessary for later computations.

This function is called after other initialization to give the helper a chance to evaluate any parameters necessary for later computations.

template<typename ShaderParameters>

miColor ShaderHelper< ShaderParameters >::computeTransparency

(

)

const [inline]

Computes transparency parameters for non-shadow rays.

This function is called to evaluate the transparency parameters for the shader on non-shadow rays.

Returns:

The transparency color for use in later computations.

template<typename ShaderParameters>

miScalar ShaderHelper< ShaderParameters >::computeSpecularGlow

(

)

const [inline]

Computes the specular glow parameters for the shader.

This function is called to evaluate any specular glow parameters to the shader for use in later computations.

Returns:

The amount of specular glow.

template<typename ShaderParameters>

void ShaderHelper< ShaderParameters >::setASQWeight	(	MayabaseState *&	MBS,
		BRDFComponent &	bc,
		const miColor &	pColor,
		const miColor &	pTransparency,
		miScalar &	pGlowIntensity
	)			const [inline]

Set the ASQ weight for this shader call.

This function adjusts the ASQ weight according to the light loop's impact on the final shader result.

Parameters:

[in,out]	MBS	The current Maya state.
[in]	bc	BRDF component information.
[in]	pColor	The diffuse color for the shader.
[in]	pTransparency	The transparency for the shader.
[in]	pGlowIntensity	The glow intensity for the shader.

template<typename ShaderParameters>

miColor ShaderHelper< ShaderParameters >::computeAmbientResult	(	const miColor &	pAmbientColor,
		const miColor &	pColor
	)			const [inline]

Computes the ambient result color.

This function computes the color returned in the ambient channel of the shader result structure.

Parameters:

[in]	pAmbientColor	The ambient color of the material.
[in]	pColor	The diffuse color of the material.

Returns:

The ambient result.

template<typename ShaderParameters>

miScalar ShaderHelper< ShaderParameters >::computeTranslucence	(	miScalar	pDotNL,
		miVector &	pLightDirection,
		miScalar	pTranslucence,
		miScalar	pTranslucenceFocus,
		miScalar	pTranslucenceDepth,
		void *	pLightBlindData
	)			const [inline]

Computes the translucence result for the shader.

This function computes the translucence result for the shader given various parameters. This result is combined with the diffuse component to produce the diffuse result.

Parameters:

[in]	pDotNL	The dot product between the light vector and the normal.
[in]	pLightDirection	The light vector.
[in]	pTranslucence	The amount of translucence for the material.
[in]	pTranslucenceFocus	The translucence focus for the material.
[in]	pTranslucenceDepth	The translucence depth for the material.
[in]	pLightBlindData	Custom light shader data.

Returns:

The translucence result for the shader.

template<typename ShaderParameters>

float ShaderHelper< ShaderParameters >::computeDiffuseAreaLightFactor	(	miVector &	pBumpNormal,
		void *	pLightBlindData
	)			const [inline]

Computes the diffuse factor for area lights.

This function computes the diffuse factor for area lights.

Parameters:

[in]	pBumpNormal	The normal after bump adjustments.
[in]	pLightBlindData	Custom light shader data.

Returns:

The diffuse factor for area lights.

template<typename ShaderParameters>

float ShaderHelper< ShaderParameters >::computeSpecularAreaLightFactor	(	miVector &	pBumpNormal,
		void *	pLightBlindData
	)			const [inline]

Computes the specular factor for area lights.

This function computes the specular factor for area lights.

Parameters:

[in]	pBumpNormal	The normal after bump adjustments.
[in]	pLightBlindData	Custom light shader data.

Returns:

The specular factor for area lights.

template<typename ShaderParameters>

miColor ShaderHelper< ShaderParameters >::getReflectedColor

(

)

const [inline]

Return the reflected color for this shader.

Return the reflected color for this shader.

Returns:

The reflected color for this shader.