Advanced foil interface law



Specular material with advanced foil interface law modelling a 3mm blue glass sheet with 8nm gold plating

Interface law The Advanced foil interface law is similar to the Thick foil interface law, but it adds the following features:

  • Custom child interface laws at both sides of the foil
  • Variable foil thickness
  • Optional birefringence anisotropy fields

The refractive indices of scene media located in front and behind the surface are taken into account, as well as the properties of the layer. The latter is defined by an internal medium defined in the law element, and a thickness shader.


Rendering tempering marks

The polarization state of light is computed accurately by this law.

This law is well suited for coated flat glass sheets and polymer foils, and can model very well glass tempering marks.


Using this feature requires an Advanced Edition license

Children Nodes

Interface law external The foil external interface law
Interface law internal The foil internal interface law
Medium medium The foil medium
Scalar shader thickness The foil thickness
Scalar shader mx2 Foil anisotropy along the x axis
Scalar shader my2 Foil anisotropy along the y axis
Scalar shader mxy Foil anisotropy along the xy axis


name type description
thickness real The foil thickness in meters

Ocean XML 3.0 example

<intlaw type="advfoil" name="intlaw">
     <intlaw type="thinfilm" name="external" thickness="8e-009">
             <medium type="linked" name="medium" target="ocean-metals::Au"/>
     <intlaw type="fresnel" name="internal"/>
     <medium type="linked" name="medium" target="ocean-building-glass::blue"/>
     <scalarshader type="uniform" name="thickness" value="0.003"/>