I run the help desk and we get asked painting and how to paint for the new sim enough for me to have this on standby . This is purely a MSFS run down. There are different implementations of PBR across the internet which is why the OP was possibly having trouble finding info. So as much as I know DCS/xplane does it a different way, not helpful for a rundown on MSFS.
Might come in handy for someone who has watched the videos and then thought I'd love to see it in action in MSFS. And ASOBO have done everyone a solid and actually let you do that. Most of it is in the SDK but it might come in handy in a different form.
It's a bit long and I dont normally receive acknowledgement from the recipient that they even got it let alone understood it but it is there to save me time when the same question comes up. YMMV
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Purely from a MSFS only point of view ( as unfortunately there are 3 major different types of PBR ) MSFS is using the metal rough workflow. To see this in action in the game
- Turn on developer mode in the options.
- Load up your favourite plane at the airport of your choice. If you are focussing on the plane a small airport.
- In the dev toolbar at the top under options, 3rd from the bottom is pbr channel.
- Turn them on one at a time to see what effect it has and what it is controlling to give you the end result.
- To go back click disabled which will render all channels together and give you your PBR compiled back.
In this submenu the ones we are mainly worried about as aircraft addon devs ( scenery may differ ) are .
1. Albedo (srgb ) this is sometimes referred to as base colour ( without the u for americans
) or diffuse channel.
This channel only holds colour info so no shading no metal roughness or anything. It is like basically saying this is red so paint it red. or asking a young 3 year old to paint a red car. They arent going to be worried about shading scratches and gloss etc.
2. Metal this is sometimes referred to as metalness . NOTE it is not the same as the other PBR type glossiness which can be made to work but shenanigans are required to convert. In this case the whiter the channel the more metal it is. Check out some glass some devs use a tickle of metal some dont.
3. Roughness NOTE it is not the same as the other PBR type called specular. Yes you can convert but shenanigans are required to convert. generally the lighter the channel the more rough it is and the darker the channel the more glossy it is. again check out some glass and or chrome to check it out.
4. NDOTL . I have no idea what it means, but it is the normal channel. The purpleish looking map. This is not a bump/height/displacement channel. often referred to as one. The easiest way to check is the colour of the map. If it is black/white it is a bump/height/displacement map and not ( yet ) used in MSFS if it is a blue/purple map it is a normal map and is used. Basically it is giving the detail like perforations on leather or carbon fibre, scratches in paint to the metal underneath etc. Not normally used for big detail.
5. AO (SRGB ) this is ambient occlusion or occlusion. It basically is the shadowing. It darkens things in holes and lightens things that are lit... To see it in real life look around the room you are in right now during the day with no lights on. Note the corners of the room and where the wall meets the floor. That darkened area or the small shadows under a picture on the wall is ambient occlusion. Devs use this to "sit you in the plane " the sim uses it to bolster it's own shadows. FSX didnt have this which is why it was often faked in the texture. P3d V4.5 introduced it and MSFS has a very good implementation of it.
From a painters point of view all of these channels would need to be done if starting from scratch if the paintkit has these channels already done for you and you can slide your decals /changes in then you really only need to worry about the albedo channel. We put the suffix _alb on ours. We are lazy . eg. left_wing_alb.dds. If there is an alpha channel that is the same as it was in FSX and used for opacity. You need the dev to have output the model with that functionality in mind so if you are trying the trick of making something invisible to hide it in sim the dev would have to output the model with that in mind.
If you dont agree with the devs roughness/metal choices - used to dirty up ,scratch or generally thump a plane then you will need to edit the roughness and metal channels in the packed file. That is the oddly coloured file. We put the suffix _comp on ours. eg. left_wing_comp.dds. You will need an editor that can show channels. Then you will be able to edit the Red channel , green channel ,blue channel .
Red = Ambient occlusion ( number 5 above ).
Green = Roughness ( number 3 above )
Blue = Metalness or metal ( number 2 above ).
Ambient occlusion ( red channel ) for a painter or repainter is hard to do as generally a dev is going to render that from the DCC package that they are using. So if the shadowing is off you can have a go at it but it might be time to contact the dev on why you think it is wrong, a possible fix, which texture it is and/or a request for a fix... nicely though, devs are people too and possibly have a folder in their email programmes where less than nice people get sent to.
And lastly if you think that rivet 169,734 is in the wrong place then you need to edit the normal map. We use the suffix _norm for that. This can be done with nvidia photoshop plugins ( or standalone normal map converters ) .Quick tip in Photoshop is to use the highpass filter on the grey scale a touch it can sharpen the normals a little. But be careful as it can introduce artifacts that look like small little pluses which will then get put into the normal and you will see it as a depression or raised little plus on your livery. Dont ask how I know!
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