OpenGL - PBR (physically based rendering)

Code samples derived from work by Joey de Vries, @joeydevries, author of learnopengl.com/
All code samples, unless explicitly stated otherwise, are licensed under the terms of the CC BY-NC 4.0 license as published by Creative Commons, either version 4 of the License, or (at your option) any later version.

[@harald9676]

I went through several of your OpenGL videos last night. I have to say you present some of the most clear and correct content on the topic I have ever come across. No waffling, straight to the point and easy to understand. Thank you

[@doriancorr]

Brian, I greatly appreciate the work you put into this subject and the accompanying book. It is concise, explained well and most of all touches on topics without over complicating them.
Kudos to you!

[@zin3408]

i can not put into words how much i needed this
thank you so much!

[@Mcs1v]

Another well detailed rendering tutorial, nice job! ;)

[@ashwanishahrawat4607]

Thanks for the explanation the shading, technique and the code.

[@NrNi9e]

Very good explanation, thanks!

[@Vagelis_Prokopiou]

Thanks for the videos Brian. Really informative.

[@whynot-vq2ly]

I wish I could give more thumbs ups, thanks for this great explanation

[@user-yc9xk7yw3g]

If i'm not mistaken, the division by PI in the diffuse component and division by 4 * NdotL * NdotV is the normalization factor for keeping our NDF normalized (equal to 1)

[@DasAntiNaziBroetchen]

"Finnell effect"
I am dying

[@beaumanVienna]

5:50 k is a function of alpha, (alpha+1)^2/8 for a direct light source and alpha^2/2 for image-based lighting
Regarding the term GGX, this is so funny, it cracks me up every time I see it. Nobody knows what it means. As in not a single person on earth. My theory: the guy who invented it was drunk and wrote it down. The next morning, he couldn't remember anything but still sent the paper to Disney. That's what happened.

[@stephenkamenar]

finally. i always wondered what pbr was. was it gpu hardware, a specific shader, or just a loose guide for standardizing material properties

[@beaumanVienna]

The line kD = 1.0 - metallic threw me off at first, but maybe now I understand. So kD+kS=1 is for dielectrics, however, conductors have also some kind of a grounding term (e.g. kD+kS+kConductiveGrounding=1)?

[@aussieexpat]

Pbr is so hot right now.

[@GeorgeTsiros]

4:18 how can the sphere reflect light from a point of its surface that is not even exposed to light? images for α 0.1, 0.3 and 0.5 i can accept, but 0.8 and 1.0 must be incorrect?

[@thehambone1454]

How would PBR work for one directional light, this is for just point lights, correct?

[@baileyharrison1030]

Use the directional light direction vector directly as the light vector. Ie, don’t subtract it from the fragment position

[@Antagon666]

What boggles my mind: is not a N dot V always negative ? Since N points outwards of object and V inwards, so the angle is always greater than 90° isn't it ?

[@baileyharrison1030]

Confuses me too. Though I’ve noticed most shaders calculate the view vector as pointing away from the fragment instead of towards.

[@yep9620]

Based you say?

[@libsadiki]

First! on Feb. 28, 2022 that is...

[@papercolor8259]

very 666

[@samuelrasquinha6712]

what the heck?

[@papercolor8259]

@@samuelrasquinha6712 which means heck amazing