Coated glass from real measured spectral data

[Soup]

I look forward to more data! It's giving really good results, and there's no better way to get good Indigo renders than with real data.

[galinette]

Dear all,

Here is some spectral angular data for blue-looking solar control glass. Currently, it is not possible to use it on Indigo, but you may use it for any test purpose.

The data corresponds to the class/coating/air interface only. For the other side (uncoated) of the glass, you should use the standard specular material of indigo, which calculates R and T coefficients from refractive indexes.

This coating is intended to be used on the indoor side of the glass (otherwise the color is less fancy). It should also be modelled as a double glazing unit to be 100% correct, the coating being inside the gas space.

To summarize the standard mounting:
outdoor air / glass / coating / gas space / glass / indoor air

Typical glass thickness is 6-10mm. Gas space is 16mm.

T coefficient is given for an angle of incidence measured on air side, whatever the direction of light is. Rair coefficient is given for the angle of incidence, that means measured in air. Rglass is given also for the angle of incidence, that means measured in glass.

Have nice material modelling! More glass data to come...

Etienne

[galinette]

I just saw a very interesting use of shaders in the 'metal temperature' topic.

To implement my coated glass shaders, I could use my tabulated data as a 2d texture (axis : angle and wavelength).

What would be required in Indigo to do this is:
- Access to the angle of incidence in the shader. This could be also calculated from the missing normal & light vectors.
- Possibility to override the R and T coefficients of the specular material, by a shader. One important thing is, R is different depending if light is entering the medium or exiting the medium.

Regards,

Etienne

[Lemo]

Hey galinette, amazing work with your materials
I saw your fake pearl, and I was wondering if this technique could be applied somehow to a "fake" coated glass as well?
I'm currently working on a wip project here, that you could be interested in.

[galinette]

Hello,

It is possible to increase the reflection only using this fake technique, and not to decrease it. Unfortunately, lens coatings are antireflection coatings so this is not possible.

It would be possible to approximate the look of antireflection lenses in reflection by using a low IOR and add the colored reflection as in the pearl, but then refraction will be wrong

Etienne

[Lemo]

Okay thanks for the details
I'll see if I can get something "convincing" enough for my purpose with the blend then

[pixie]

bumping interesting threads should be a profession!

[galinette]

Undertaker is a profession! That post was six feet under.

[pixie]

Undertaker is a profession! That post was six feet under.

And yet one would still get amazing results from indigo even then!

[beche]

Hello, I try to win the undertaker challenge championship !
I m interested in any solution on how to process mesured data of glasse in Indigo.
@galinette did you find a solution ?

[Jay-ko]

I think so

Have you seen the material provided here?
https://indigorenderer.com/materials/materials/1019


What is your kind of data?

[Zom-B]

There is also some private encoded data possible that Saint-Gobain Glass uses for materials to hide the raw data and keep it save still alowing to render it:

https://indigorenderer.com/materials/ma ... iew_source

[beche]

Thanks folks,

Yes I was aware of that private data from SGobain.
But what I have is a specific mesured glass data that I want to input inside indigo/xml (no need to encode it).
Is there a way to do this the same way as SGobain did it ?
I don't need to use the same data as SGobain (don't know what it is made of).

[Tyler]

Hi there,

does someone would know how to make an Anti Refractive coated Glass material?
thanks