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titleGlow Parameters

Glow Parameters

Glow can make an object appear to emit light. This is useful when you need a textured effect like lit panels, circuitry, or other complex effects with local influence in lighting.

 

 

Gain

Glow gain or weight.

 

 

Color

Controls the incandescence color, or glow, of the material.

 

  

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titleReflection & Refraction Parameters

Reflection/Refraction Parameters

Refraction Gain

Refraction gain.

Reflection Gain

Reflection gain.

Refracton Color

Refraction color.

Roughness

Refraction and reflection roughness.

Refractive Index

Index of refraction.

Thin

If on, correctly split energy according to Refractive Index between reflection and refraction, but do not bend the ray in refraction (simulating a double pane of glass with a single pane).

Interior Parameters

Single Scatter Albedo

Single scatter albedo. Connect this to a 3D pattern to control the intensity of the scattering.

Single Directionality

Controls the directionality of the scattering.0 : isotropic1 : forward-1 : backward

Extinction

Extinction color. Connect this to a 3D pattern to control the density of the interior.

Integration Mode

Control volume integration type:Ray MarchingRatio Tracking. Unused, this is currently internal to the PixarAnimation Studios.

Min Extinction Color

Minimum extinction color.

Max Extinction Color

Maximum extinction color.

Step Size

Ray marching step size. Step size is based on the resolution of the 3D pattern that is connected. Inadequate step size will produce artifacts.

Max Steps

Max number of steps.

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titleGlobal Properties Parameters

Properties Parameters

Bump

Normal to use for all illumination unless it is overriden by the individual lobe's bump normal.

Presence

Connect a mask here to apply a cutout pattern to your object. Presence is defined as a binary (0 or 1) function that can take on continuous values to antialias the shape. Useful for creating leaves and other thin, complex shapes.

IMPORTANT NOTE: This value should be either 0 or 1. A value between 0 and 1 will produce unwanted noise !!!

Presence Cached

Specify whether presence is cached or not.

Shadow Mode

Shadow opacity computation mode:

  • Shader and shadow color (0)
  • Shadow color only (1)

Shadow Color

Specify shadow color.

Specular Energy Compen

Applies fresnel energy compensation to diffuse and subsurface illumination lobes. A value of 1.0 attempts to fully balance those illums by darkening them against the specular and rough specular illumination responses.

Specular and Rough Specular roughness are also taken into account. The effect fades off as specular face or edge color approaches 1.0, so metals can add a diffuse baseline.

Clearcoat Energy Compen

Applies fresnel energy compensation to all lobes other than clearcoat itself. A value of 1.0 attempts to fully balance those illums by darkening them against the clearcoat illumination response.

Clearcoat roughness is also taken into account. The effect fades off as clearcoat face or edge color approaches 1.0, so metals can add a diffuse baseline.

Irradiance Tint

A tint applied to illumination before being scattered by subsurface or single scatter.

Unit Length

Subsurface and single scatter unit length. It is a multiplier on Mean Free Path Distance. Mean Free Path Distance is often measured in millimeters. If the scene is modeled in some other scale, Unit Length should be set accordingly. The default value of 0.1 is appropriate for scenes modeled in centimeters and Mean Free Path Distance measured in millimeters.

Utility Pattern

Note that there is no inputAOV in PxrSurface because we can wire the connection to the utilityPattern instead. It produces the same result as inputAOV. Utililty pattern can be used for other purposes.

It is a dynamic array of utility patterns that get evaluated but their results are not used by this bxdf.

A utility pattern is useful to find out how much this object gets sampled and for collecting statistics so you could theoretically prune and optimize the scene. Once this information is collected, you should disconnect the utility pattern because it is expensive to evaluate. Also, if you need to collect information about shadow rays, you need to set the Shadow Color to greater than 0.0 so the utility pattern is invoked.