LightingFunctions.md

Lighting Functions

Half Direction

Description	Node Showcase:
Calculates the direction vector halfway between two vectors A and B.

Input	Type	Description
A	Float3	The first vector, Vector A.
B	Float3	The second vector, Vector B.

Output	Type	Description
Half Direction	Float3	The halfway vector between Vector A and B.

L dot H

Description	Node Showcase:
Returns the dot product between the Light direction and the Half-way direction between the View and Light direction.

Input	Type	Description
View Direction	Float3	The camera view direction.
Light Direction	Float3	The light direction.

Output	Type	Description
LdotH	Float	The dot product value.

L dot V

Description	Node Showcase:
Returns the dot product between the Light direction and the View direction.

Input	Type	Description
View Direction	Float3	The camera view direction.
Light Direction	Float3	The light direction.

Output	Type	Description
LdotV	Float	the dot product value.

N dot H

Description	Node Showcase:
Returns the dot product between the surface Normal and the Halfway vector between the View direction and the Light direction.

Input	Type	Description
Normal	Float3	The surface normal in world space.
View Direction	Float3	The camera view direction.
Light Direction	Float3	The light direction.

Output	Type	Description
NdotH	Float	the dot product value.

N dot L

Description	Node Showcase:
Returns the dot product between the surface Normal and the Light direction.

Input	Type	Description
Normal	Float3	The surface normal in world space.
Light Direction	Float3	The light direction.

Output	Type	Description
NdotL	Float	the dot product value.

N dot V

Description	Node Showcase:
Returns the dot product between the surface Normal and the View direction.

Input	Type	Description
Normal	Float3	The surface normal in world space.
View Direction	Float3	The camera view direction.

Output	Type	Description
NdotV	Float	the dot product value.

R dot V

Description	Node Showcase:
Returns the dot product between the Reflection direction and the View direction.

Input	Type	Description
Light Direction	Float3	The light direction.
Normal Direction	Float3	The surface normal in world space.
View Direction	Float3	The camera view direction.

Output	Type	Description
RdotV	Float	the dot product value.

Reflect Direction

Description	Node Showcase:
Calculates the direction a light ray would reflect against a surface.

Input	Type	Description
Light Direction	Float3	The light direction.
Normal Direction	Float3	The surface normal in world space.

Output	Type	Description
Light Direction	Float3	The reflection direction.

Schlick Fresnel

Description	Node Showcase:
Implements the Schlick Fresnel specular term.

Input	Type	Description
Specular Colour	Color	The Colour of the surface.
Light Direction	Float3	The light direction.
View Direction	Float3	The camera view direction.

Output	Type	Description
Schlick Fresnel	Color	The fresnel colour.

ShadeSH9

Description	Node Showcase:
Implements the Unity ShadeSH9 function. This allows for real time lighting usage in shading.

Input	Type	Description
Normal	Float3	The surface normal in world space.

Output	Type	Description
SH Shading	Float3	The Shading values.

SHEvalLinearL0L1

Description	Node Showcase:
Implements the Unity SHEvalLinearL0L1 function. This combines the Spherical Harmonics matrix's L0 and L1 coefficients.

Input	Type	Description
Normal	Float3	The surface normal in world space.

Output	Type	Description
Spherical Harmonics	Float3	The L0 and L1 coefficient combination.

SHEvalLinearL2

Description	Node Showcase:
Implements the Unity SHEvalLinearL2 function. This is the highest frequency band of the Spherical Harmonics.

Input	Type	Description
Normal	Float3	The surface normal in world space.

Output	Type	Description
Spherical Harmonics	Float3	The L2 Spherical Harmonics band.

SH Get Basis Vectors

Description	Node Showcase:
Gets the local XYZ coordinate space of Unity's Spherical Harmonics matrix (SHa terms).

Output	Type	Description
Harmonic XYZ	Float3	The basis vectors of the Harmonics.

V dot H

Description	Node Showcase:
Returns the dot product between the View vector and the Halfway vector between the View and Light direction.

Input	Type	Description
View Direction	Float3	The camera view direction.
Light Direction	Float3	The light direction.

Output	Type	Description
VdotH	Float	the dot product value.