Why do we use only specular dds for IBL?

How does Babylon handle the diffuse irradiance?

Does that help: Master Physically Based Rendering (PBR) - Babylon.js Documentation ?

Hi Deltakosh,
Thanks for the link. I am still confused somehow. As far as I know, we could use a convoluted texture to model the irradiance (diffuse) part. So how can we eliminate this one in Babylon? Is there a white paper or something which explains this technique in detail? :grinning:

If you read shaders then you can go there:

But else we implement the Disney BRDF.

Not sure though to get your question :slight_smile: You want to eliminate the irradiance?

No I don’t want to eliminate the irradiance. I just wonder how we can calculate the diffuse without an irradiance map? :slight_smile:

Ah! I vaguely remember that Babylon use Spherical Harmonics to handle the irradiance instead of irradiance map. I will dig more in the implementation detail.

Here I see Irradiance Jones.

How ever I have trouble to find the original white paper. Could you please help me if you know where I can find the original paper?

Many thanks!

Pinging @sebavan who wrote the shader

No paper on this one, a friend of mine created it :slight_smile: and I blindly trusted and reused it knowing the sh were giving the same results for a bit more compute if I remember well.