The Iridescent material is both reflective and iridescent. The material is composed of a diffuse and reflection component. It approximates the property of surfaces that have their reflected color varying in function of the angle of view and the angle of light.
It simulates a surface made by thin film layers separated by air spaces, resulting in a rainbow effect like on soap bubble, sunglasses or butterflies wings. This material supports reflection caustics.
The diffuse component of the material is controlled by a set of attributes which defines the diffuse diffusion of the material.
|Diffuse Brdf||Define the BDRF model used for the diffuse component. The material supports 2 models: Lambert (extended) and Oren Nayar|
|Diffuse Color||Define the diffuse color of the material.|
|Diffuse Gain||Define the gain of the diffuse reflection.|
|Diffuse Roughness||Define the surface roughness of the diffuse component.|
The reflection component of the material is controlled by a set of attributes which defines the reflectivity of the material.
|Reflection Color||Define the color of the reflection.|
|Reflection Gain||Define the gain of the reflection.|
|Reflection Exit Color||Define the color returned by the path tracer when the path has reached the maximum reflection depth set in the path tracer.|
|Fresnel Ior||Define the index of refraction of the surface.|
|Reflection Roughness||Define the surface roughness of the reflection component.|
The material supports Roughness and multiple microfacet models that can be selected using the Brdf attribute.
|GGX||GGX distribution results are very close to empirical data.|
|Ward||Ward distribution is very close to Beckmann's but behave quite differently with anisotropy|
|Beckmann||Beckmann distribution tends to provide sharper reflections when compared to GGX|
The iridescence effect is controlled by a set of attributes which defines the physical property of the material.
|Iridescent Exposure||Define the exposure of the iridescence.|
|Iridescent Power||Define the exponent for the iridescence which corresponds to the interference power that is proportional to the number of thin layers constituting the material.|
|Iridescent Film Thickness||Define the thickness of the film layers (in nanometers) through which the light is refracted.|
|Iridescent Air Thickness||Define the thickness of the air layers (in nanometers) which corresponds to the spacing between the thin film layers.|
|Iridescent Diffuse||Enable the iridescent absorption on the diffuse component of the material.|
|Iridescent Reflection||Enable the iridescent absorption on the reflection component of the material.|