P3D v4 PBR versus not PBR

Christian Bahr

Resource contributor
Hi.

The difference between PBR and non-PBR textures/material on the Cub can be clearly seen. Not too dominant but easily recognizable.

Can I also show my PBR models here? :)
 
This is an excellent example of where PBR is prudent and where it is not. Most airplanes, airliners...have a really rough finish (fine sandpaper like). They are mostly dull except for the bare metallic surfaces. PBR IMO, exaggerates the environment effect.

The car model however........cars have super smooth clear coated finishes. PBR works greatly there, very realistic.

The Tiger Moth however, has a very nice balance. Very well done, I would not expect to see much effect on the fabric, but very noticeable on the prop which is typically gloss varnished.

David
 
A

Aviasim

Guest
This is an excellent example of where PBR is prudent and where it is not. Most airplanes, airliners...have a really rough finish (fine sandpaper like). They are mostly dull except for the bare metallic surfaces.
To be honest - I have never seen an aircraft with such a finish - IMO, "really rough, fine sandpaper like" is not very aerodynamic, aircraft painters are hell bent on getting the best, lightest finish to bring down FUEL cost. It'd literally make no sense, in either way you look at it, to have a "really rough finish" - I'm calling rubbish on that one.
 

=rk=

Resource contributor
Ok now also be honest, do you walk around the tarmac, rubbing nacelles and wings? Because you can't see a pitted finish, even from inside the cabin, just like you can't see the dimples in a golf ball, until you look very closely. Golf balls are very shiny, btw and the dimples make them fly farther by employing "boundary effect."

I don't know if you realize, but it is a very severe environment and things deteriorate!



This excerpt from Boeing:

"MAINTENANCE
Beyond the need for washing, the comparative cost of maintaining painted and polished surfaces is significantly affected by the policies of individual operators. Most repaint their airplanes every four years, often during a scheduled C- or D-check, but do not completely strip the paint during each cycle. Instead, they alternate between complete stripping and merely scuff-sanding the existing paint layer and applying a new topcoat. Painting costs include labor, stripper, paint, primer, masking materials, and proper disposal of consumables.

Airplanes should never carry more than two layers of paint. With more than two layers, operating efficiency drops, inspections become more difficult, and corrosion can start in chips that remain under a fresh topcoat. Excessive paint buildup is a particular concern on aging airplanes, as the buildup may cause difficulty during inspection of the rows of rivets and lap splices that connect fuselage panels.

Maintaining the appearance of a polished airplane requires repolishing up to three times a year with a special compound applied with mechanical buffers, as well as regular washing to clean oxidation buildup from unpainted surfaces. Both activities require a considerable investment in buffing equipment and personnel. Periodic maintenance can be performed while a polished airplane is being repolished, but not while a painted airplane is being stripped and repainted.

While the lighter weight of a polished airplane saves fuel costs, as shown in (table 1), this savings is more than offset by the higher cost of washing, polishing, and painting a polished fuselage throughout its service life (table 2). The net operating cost of polished airplanes, calculated as a percentage of the total operating cost, is between 0.06 percent and 0.30 percent more than the total operating cost of fully painted airplanes."

https://www.boeing.com/commercial/aeromagazine/aero_05/textonly/fo01txt.html

So by extension, if a plane is painted, there is no polishing done whatsoever.

 
To be honest - I have never seen an aircraft with such a finish - IMO, "really rough, fine sandpaper like" is not very aerodynamic, aircraft painters are hell bent on getting the best, lightest finish to bring down FUEL cost. It'd literally make no sense, in either way you look at it, to have a "really rough finish" - I'm calling rubbish on that one.
You must not work around airplanes. Or you are clueless as to what fine sandpaper porosity is. I'll give you an example, and then you can go "rubbish" by yourself. A typically military gray new paint job will be like an 800 grit sandpaper. If you rub oily hands in it, the stain will likely become permanent. That surface finish may actually become so rough with time, that you can get a bruise if you are not careful. On well flown airliners, that porosity is mostly due to air friction "biting" into it over the years, salt damage, and severe orange peeling of the finish. Of course, a brand new fresh of the booth airliner will be very shiny at first....but that's not what I was referring to. We typically don't sim airplanes fresh of the hangar, and the better developers know well how to weather an airliner.

Rick gave you some good examples above. But if you'd rather have a Deltron 3000 finish on your 787, go for it! I may even paint it for you ;-)
 

Christian Bahr

Resource contributor
I'm calling rubbish on that one.
It is really a pity that you see it that way! It can be assumed that the contributor was not interested in drawing an absolutely realistic comparison of an aircraft paint or wing covering. It's about making a comparison between PBR and non-PBR. That's been done very well by Anthony31 :)
 
Many thanks to Anthony and Christian for posting actual "worked examples" ...rather than just commentary. :cool:


Might this distinguish 'real' FS developers from 'virtual' FS developers in this forum ? :scratchch



And now for something completely ...different (?) :p


"I just realized that Howard wasn't concerned about smooth rivets due to drag reduction as much as he was enabling his OCD for that smooth texture"

Code:
https://www.youtube.com/watch?v=bSw9A-ZIo8M


GaryGB
 
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=rk=

Resource contributor
Rick gave you some good examples above.
Ty, I'd observe the US Airways livery is the best example of friction induced degradation, with the exception of the nose cone. The reinforcing ribs imply it is flexible and the impact damage at the extreme front, demonstrates the paint is more brittle than the underlying material and consequently "chips off," while it seems possible that the fairer angles of the cone actually serve to adhere the finish, by giving just enough, but not too much as to delaminate the paint. Notice how clean the cone looks on the United livery.

Another thing I find interesting, is what I would guess to be drag induced wear. You see large patches of bare white, just behind the cockpit, about where the vortices breaking away from the glass would swirl. Also behind the front door of one of the United 747's and just in front of the wing root fairing of the same plane.

Something to consider when texturing for reality.

Might this distinguish 'real' FS developers from 'virtual' FS developers in this forum ?
It might, indeed, unless Anthony linked a video of his Tiger Moth, being used in a scene from The Aviator.
 
AFAIK, the subject of this thread is:

PBR versus not PBR

...with posting of "worked examples".


I am doubtful the OP was intended to make this a thread about the whys and wherefores for- and against- PBR being implemented. :rolleyes:

Rather IIUC, it was intended to show what it looks like in MSFS / P3D with- and without- PBR having been implemented on 3D models. :pushpin:


I believe that given the complexities involved with PBR being implemented on 3D models with currently available utilities / methods, a thread such as this would be very useful for FS Developers (whether 'real' or 'virtual' at this point in time) to see more "worked examples" that may be considered when making a decision as to whether, when, and how- ...they may implement PBR on 3D models in the future.


In keeping with the usefulness of the above "worked examples", IMHO it would be even more useful to have a brief summary description of the currently available utilities / methods used for the 3D models that do have PBR implemented posted along with a screenshot from FS ...within a thread such as this. :idea:

Many thanks in advance to Anthony and Christian if they would be so kind as to revisit this thread, and post a brief summary description of the currently available utilities / methods used for the 3D models that do have PBR implemented in their above screenshots from FS. :teacher:



PS: I also believe it would be useful that images taken from a 3D modeling / rendering application (rather than from a run time 'Flight' session in FS, be kept in a separate thread elsewhere ...along with off-topic discussions as to the whys and wherefores for- and against- PBR being implemented).

Hmmm... "Flight"' ...oops... I used the "F-word" at FS Developer again (twice in one post) ! :laughing:


GaryGB
 
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A

Aviasim

Guest
All your examples are of very old planes, clearly. The point is that a new paint scheme does NOT have a sandpaper finish - military wasn't even mentioned until he tried to back himself up. Of course the paint pits and chips - this is why they are given a new paint..and it is NOT smooth/rough finish regardless. I will say though, even military planes didn't have a rough finish, just a matte paint - but clearly if you show me a plane that has had thousands of hours flight time and use it as an example to back your argument, don't make it contradicting. The point is - NOBODY will paint an aircraft/airline and give it a rough finish, maybe in the 1920's, definitely not now

@pinkjr Calm down, you could have made your own point more clear and you didn't even mention military planes, you said all aircraft/airlines - neither did you say after X thousand hours the paint becomes rough. I spend a lot of time around aircraft, or are you yet another FSDeveloper wizard that can see in to my life to say/assume otherwise, getting all too common here at FSDeveloper. "Let's make a false claim and then defend it by throwing in false accusations and a bit of name calling". Join the rest, pink.
 

=rk=

Resource contributor
All your examples are of very old planes, clearly. The point is that a new paint scheme does NOT have a sandpaper finish - military wasn't even mentioned until he tried to back himself up.
Not sure your point, actually. There was no presumption, nor affirmation that the Tiger Moth and Porsche represented new finishes, however there is a VERY VALID distinction between the two, PBR and otherwise, that is not at all elucidated, or disproven, by your assertion about new liveries, so it doesn't serve to add any clarity, imo. The remainder of the post appears to be off topic vitriol.

The point is - NOBODY will paint an aircraft/airline and give it a rough finish, maybe in the 1920's, definitely not now
.
All jets, so they probably were post 1930:



Except maybe a noob.



...with posting of "worked examples".
SO far, we've seen anything but that from you.
 

Christian Bahr

Resource contributor
SO far, we've seen anything but that from you.
I take that part over, if I may. with pleasure :)

It is not so easy to approach the subject of Physical Based Rendering, PBR for short ;)

Because it is the one 3-D objects with the new PBR material to provide, which is quite easy, and the other is to then equip the objects with real PBR textures. So if you want to create a "PBR Add-On", then it is not enough to just apply PBR material to objects, you also have to create PBR textures. This is initially associated with some time and effort, as you have to know how to create such PBR textures. That means you have to read a lot and understand the basics of PBR. But gradually the veil clears around PBR and there are first presentable results:

1_p3dv4_pbr_pilot_reflektionen.jpg


Here in the picture you can see the airport avatar Chesley. He "wears" different PBR textures. Its safety vest consists of a PBR texture that makes the stripes reflect the light more than the rest of the vest.


2_p3dv4_pbr_pilot_metall_reflektionen.jpg


But not only the vest reflects the light. The emblem on the cap, which is made of metal, reflects the light. The avatar is composed of different PBR materials and PBR textures for clothing, skin, flashlight, cap etc :)


For example, all objects at my EDLE Essen/Mülheim Airport have now been completely equipped with PBR material. In some cases, PBR textures have already been created, such as for the gas station, the follow-me vehicle and the glass on the terrace:

4_p3dv_pbr_glas.jpg


The glass panels of the terrace are made of a handmade PBR texture. Impurities can be seen in the glass from certain viewing angles. In addition, the incident light is reflected and it reflects the environment in the glass.

3_p3dv4_pbr_material_texturen.jpg


At the entrance to the fire department you can see small reflections of light. They are also generated by a PBR texture.

PBR may perhaps be described by the fact that the light calculations in the P3Dv4 take place according to physical laws. This makes it easier for the individual developer, since he no longer has to make countless material settings and no longer has to interpret how an object, be it made of glass, metal, plastic or fabric, reacts to light. Now only very few material settings have to be made. Here is an example of the conventional P3Dv4 material settings ....

p3dv4_material.jpg

The setting options in the conventional P3Dv4 material editor (marked in red) are relatively extensive!

p3dv4_pbr_material_texturen.jpg

Looks pretty clear, the material settings for PBR :)

Here are a few pictures ... from Paros ... from Mülheim ...


p3dv4_paros_porsche_pbr_3.jpg




p3dv4_porsche_pbr_1.jpg

Porsche with PBR Material and PBR Textures


p3dv4_porsche_pbr_2.jpg

Antonov AN-2 with PBR Material and PBR Textures

Everything is not perfect yet! But is a start :wizard:
 

=rk=

Resource contributor
It does look really immersive. What I'd like to see is differential reflection, from any other source than environment. Granted, Chelsey's vest reflects sunlight differently than does the orange nylon, are you able to exaggerate it's reflection of effect generated lights, as compared to the less reflective orange nylon?
 

Christian Bahr

Resource contributor
It does look really immersive. What I'd like to see is differential reflection, from any other source than environment. Granted, Chelsey's vest reflects sunlight differently than does the orange nylon, are you able to exaggerate it's reflection of effect generated lights, as compared to the less reflective orange nylon?
I can do that. But do not know exactly what effect the vest should have. Did you think it should be completely metallic and have the reflective properties of polished paint?

2019-10-17_19-4-23-431.jpg


The light source is dynamic lights attached to the gas station. And from behind comes the light of Spots attached to the main building. Die Weste hat in etwas die Reflektionseigenschaften wie der Lack des Porsche. But the difference is that the vest has a fabric structure!
 

=rk=

Resource contributor
Not polished paint. I'd think it would be obvious that we would want the reflective stripes to be highly reflective, upon an instance of effect light, similar to this:

FSX eve.JPG




and otherwise as dark, relatively, as the rest of the clothing. The above is simply a night texture that demands the presumption of reflectable light.
 

Deano1973

Resource contributor
I'm probably out of my depth here, but regarding PBR - there doesn't seem to be anything that it does that cannot be done with a good combo of bump, diffuse and speculars ( with alphas ) and the various reflectivity settings within the sim. Am I missing something - does PBR make this process easier? I can of course see the positive effect that it has, but as I haven't tackled it yet within my workflow I suppose I just haven't understood precisely the advantages of using it. Perhaps with the new crop of sims PBR's effects show more clearly than in P3D.
 
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