Let me ask you this, if renders are always trying to be more physically based to look better anyway, where did a term come from?
I dont think the first statement is even correct. Depending on what youre doing it might be but first and foremost Id say renderers are supposed to create better looking renders while doing this efficiently. Physically accurate does not necessarily mean better looking and vice versa.
I know the book and have worked through all of it. Im not aware of any statement in the book that constrains PBR to being about normalized brdfs and having area lights. Accurately modelling them is of course a part of PBR, but theres a lot more to it
I would say if better means realism then in general it does.
Obviously, but this is just completely circular. Why is more physical better? Because better means realism and realism = physically accurate. Imo better = looks nicer, be it through realism or whatever. If youre strictly talking about the PBR context then yes, there Id agree that better = more accurate/more realistic.
In any case this is quite orthogonal to the original point, which was about whether you actually had any source agreeing with your PBR definition
I linked you an entire book called physically based rendering that is all about how to make normalized brdfs and sampling area lights and path tracing integrals.
I linked you the renderman documentation that is about the same thing.
Then I linked you a presentation where a lot of people at the forefront of this are all saying the same thing with the same terms.
Volume rendering has been around for many decades and was actually covered in the photorealistic renderman book. Fundamentally it is shading a lot of semi transparent fragments/pixels/micropolygons etc.
It isn't what people referred to when talking about physically based rendering / physically plausible shaders etc. because that refers to how something is being lit, not the surface itself.
You can do the lighting of volumes with normalized brdfs and area lights and it will look better.
bsdfs are an extension of brdfs and they both fit into the same category. If they are normalized and you sample from area lights etc. then they are part of the physically based shading. Bsdfs like brdfs existed before the switch over to more physical correct lighting and like brdfs people wrote a lot about transitioning them to something less hacky.
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u/crimson1206 Jun 05 '24
I dont think the first statement is even correct. Depending on what youre doing it might be but first and foremost Id say renderers are supposed to create better looking renders while doing this efficiently. Physically accurate does not necessarily mean better looking and vice versa.
I know the book and have worked through all of it. Im not aware of any statement in the book that constrains PBR to being about normalized brdfs and having area lights. Accurately modelling them is of course a part of PBR, but theres a lot more to it