Advanced Lighting Override Material
 
 
 
Command entry: Material/Map Browser Materials Standard Advanced Lighting Override
NoteThe Advanced Lighting Override material appears in the Browser only if the currently active renderer supports it.

This material lets you directly control the radiosity properties of a material. Advanced Lighting Override is always a supplement to a base material, which can be any renderable material. The Advanced Lighting Override material has no effect on ordinary renderings. It affects the radiosity solution or light tracing.

Advanced Lighting Override has two main uses:

As the rollout for the Advanced Lighting Override material states, you don’t have to apply this material to obtain a radiosity solution, and most models will never require it.

ImportantThe mental ray renderer does not support the Advanced Lighting Override material.

Obtaining a Better Image

Materials that use default settings can be highly reflective. This can lead to overexposed or washed-out radiosity solutions. In general, the best way to adjust this is to reduce the HSV Value (V) of a material color; or, for a bitmapped material, reduce the RGB Level. In some situations, Radiosity Override can improve the appearance of the radiosity solution. Examples of situations where Radiosity Override can help include color bleeding and large dark areas:

Creating Special Effects

Self-illumination makes an object appear to glow in ordinary renderings, but does not contribute energy to the radiosity solution. To have radiosity processing take a self-illuminating material into account, make this material the base material of Advanced Lighting Override, then increase the value of Luminance Scale.

Upper left: By default, self-illuminated neon lights do not influence the scene light.

Right: Advanced Lighting Override material scales the neon lights’ Luminance so the radiosity solution can take it into account.

Luminance scale takes the Self-Illumination map into account. You can use this to model effects such as a computer monitor in a darkened room.

The Special Effects group of the Advanced Lighting Override material also has a control for adjusting the quality of the Bump map in areas of indirect lighting.

Procedures

To adjust a material’s reflectance and transmittance, do either of the following:

To make a self-illuminating material emit radiosity energy, do one of the following:

Interface

Override Material Physical Properties group

These parameters control the base material’s advanced lighting properties directly.

WarningThere is no problem with reducing the default scale, but increasing it for any of these parameters might cause colors to “burn out”: If the scale is too great, they render as pure white, appearing overexposed.
Reflectance Scale

Increases or decreases the amount of energy the material reflects. Default=1.0.

Reflectance Scale increases or decreases the energy of reflected rays.

TipTo increase self-illumination, use Luminance Scale in the Special Effects group, not this control.
Color Bleed

Increases or decreases the saturation of reflected color. Default=1.0.

Color Bleed increases or decreases the saturation of reflected color.

Transmittance Scale

Increases or decreases the amount of energy the material transmits. Default=1.0.

Transmittance Scale increases or decreases the energy of transmitted rays.

NoteThis parameter affects only radiosity. It has no effect on light tracing.

Special Effects group

These parameters relate to specific components in the base material.

Luminance Scale (cd/m^2)

When greater than 0, scales the self-illumination component of the base material. Use this parameter to have self-illuminating objects contribute energy to the radiosity or light-traced solution. Cannot be less than zero. Default=0.0.

Typically, a value of 500 or more will give good results.

Indirect Light Bump Scale

Scales the effect of the base material’s Bump map in areas lit by indirect light. When this value is zero, indirectly lit areas are not affected by Bump maps. This value does not affect the Bump amount in areas where the base material is lit directly. Cannot be less than zero. Default=1.0.

TipThis parameter is useful because indirect bump mapping is simulated and not always accurate. Indirect Light Bump Scale lets you adjust the effect explicitly.

_____

Base Material

Click to choose or edit the Base material. You can also replace the base material with a different material type.