Learning PBR with chests
polycounter lvl 8
That's it, I'll finally try to get into PBR stuff, even if I don't really like realistic graphics. So I started a simple chest, nothing fancy, and here is where I am after some hours of reading everything I found on this site and eslewhere.
I'm using UE4 so, Metalness workflow. Had a hard time figuring why it looked bad, I didn't know there were different workflows, and almost every info I found was therory related, nothing practical explaining in detail how to create textures for PBR.
Keep in mind it's just a work in progress test, not final at all.
- the albedo. I just used an equalized wood texture. The metal is painted black, so I don't define it as metallic. The rivets and lock are metallic, so their reflection color is defined by the albedo ( gold-ish color ).
- the metalness, pure black and white. I wanted to show the metal under the paint in some areas so I added some spots. Doesn't look really good, it seems really hard to control the transition between materils, right ?
- the roughness. I used the wood texture and some metal texture to add variations. Not sure if it's a good idea, but it looks too "smooth" without it.
- the normal map, nothing special here.
- final result
Now, I have a problem with the ambiant occlusion, when I plug it into the AO slot, nothing happens, the AO just doesn't show up. So I cheated and added it in the albedo. I know it's bad, but seriously having assets with no prelight at all just feels really boring and bland.
Now I'm a big noob in PBR so I'm waiting for you to destroy what I've done, so I can correct everything ^^.
I'm using UE4 so, Metalness workflow. Had a hard time figuring why it looked bad, I didn't know there were different workflows, and almost every info I found was therory related, nothing practical explaining in detail how to create textures for PBR.
Keep in mind it's just a work in progress test, not final at all.
- the albedo. I just used an equalized wood texture. The metal is painted black, so I don't define it as metallic. The rivets and lock are metallic, so their reflection color is defined by the albedo ( gold-ish color ).
- the metalness, pure black and white. I wanted to show the metal under the paint in some areas so I added some spots. Doesn't look really good, it seems really hard to control the transition between materils, right ?
- the roughness. I used the wood texture and some metal texture to add variations. Not sure if it's a good idea, but it looks too "smooth" without it.
- the normal map, nothing special here.
- final result
Now, I have a problem with the ambiant occlusion, when I plug it into the AO slot, nothing happens, the AO just doesn't show up. So I cheated and added it in the albedo. I know it's bad, but seriously having assets with no prelight at all just feels really boring and bland.
Now I'm a big noob in PBR so I'm waiting for you to destroy what I've done, so I can correct everything ^^.
Replies
Just messing your box looks lovely. I'd turn that AO off though, because its in your diffuse its getting cut off by specular highlights and looking really fake. let unreal do that stuff for you when you bake lights
Also, your texture has no large scale variation. Try and work in some larger texture information that plays on local forms. This doesn't have to be dirt or damage either.
I've never had the AO do anything for me in UE4 either. I gave up on even bothering:
https://answers.unrealengine.com/questions/101059/ambient-occlusion-node-in-material-does-nothing.html
I really jumbled my words there..
simply put, I think the gaps in the wood need to be more visible.
As sort of a compromise between having a dedicated texture to ao if you for some reason don't want one, you can always use an AO map as more of a "dirt" pass, so while it's darkening up where the edges meet in corners (basically what ao is for) it doesn't look "false" when hit by direct light as it'll read more like dirt than shadow. I've currently been experimenting with this using a curvature and AO map in substance painter, and then going on top of a mask with a brush to get rid of some of the uniformity that comes with this method. I was doing everything manually with photo refs in photoshop across all the different maps for a bit, but am finding myself moving towards painter to minimize the going back and forth between all the files. (Photoshop still being used for stuff like making black+white maps to mask out things with the more advanced selection tools which I can then import and use in painter, or to put in specific details like icons/logos/text stuff without having to use the awkward stencil for it + ndo2)
I'm also unsure as to why your metal trim is not reading as metal in the metalness map at all. With the metal trim being completely black in your metalness map it's going to read more like plastic. I believe even painted metal will have some sort of value going on other than black although I'm not a 100% sure. I find myself using values in between for materials that are not 100% metal only yet definitely not black either. (Usually due to the material being a painted metal or compound, definitely a wider range of values when having dirt and grunge mixed on top of a metal part) The harsher black to white transition does work well though for things like paint chips/flakes which have a strong contrast by nature. I'd guess I'd play around with having your metal trim in the metalness map set to different values to see which one looks the best to you.
I still say trust your eyeballs on what looks the best when it comes to PBR. Especially since there are multiple styles of handling textures, although anyone can feel free to disagree with me on that
As a last suggestion, perhaps you could make it so the texture is a bit more grounded in how it would be "dirtified" in real life. IE dust landing on the top parts of the chest, dirt/grunge/scratches being more towards the bottom from the floor, and any areas handled the most. I believe you can pull off these effects a little easier by baking out a world normal map and using that to help get you started.
The albedo is just a base for now, I just wanted to put the materials right.
From what I've read, the metalness should always be black or white, never inbetween, and a painted metal is not considered metallic, unless it's a "metallic" paint of course. Now PBR is still a bit new, I know some people think we should apply the theory and others say we should adapt it to what looks better for us... honestly I've never seen a next-gen game with PBR that is perfectly used, most of the time the graphics look weird, we can clearly see objects made of a plain color albedo with a normal map, it's kinda bland imo.
I also removed the AO from the albedo. Now I'll try to work on the albedo itself.
Agreed
Is the wood a tiling texture by any chance or is it sculpt/retop/bake.
Just wondered if you modelled a low poly and used tileables from the get-go.
IMO the best is the 2nd version! Keep em coming!
Coming along nicely!
Shapewise:
Love the first 2 boxes for their authentic shape, the third one looks more of a table/stand then a chest.
Materials:
The metal looks solid, the only remark there is maybe a little more variation in roughness, but that can be personal choice.
As for the wood it looks to flat, quite uninteresting perhaps. A great source for inspiration is the art dump from Assassin's creed.
Found here ( link to page 2 for materials in specific )
http://www.polycount.com/forum/showthread.php?t=144111&page=2
Preview below.
As you can see the wood has much more variation in terms of roughness, you could make the dark parts of your wood a high roughness maybe 0.8 (just guessing here ) and the light parts 0.3 maybe?
(these values are in Unreal engine terms ofcourse)
Really hope this helps. Love to see more!
Luxap : yeah I know the third one is more like a trunk than a chest, you know the kind of trunk you put kids toys inside.
I guess you're right for the wood, I'll try to put more variation in the roughness.
Unrelated to the texturing, I have a hard time figuring out how to have good shadows, as you can see most of the self-shadowing looks bad, or even absent. I tried changing the shadow bias, but it results in "stripes" all over the scene. The scale of the meshes should be good, I made them based on a human from one of the demo scene, so the chests are like knee-high.
Also the AO doesn't seem to do shit, is that normal ?
While AO shouldn't techincally be in the diffuse, I have put a small amount of it into most of my projects. I don't really see the problem if it looks good?
I just submitted this to the unreal marketplace, here are some shots. Tricounts may seem high but I've put champfers and custom normals almost everywhere to have clean bakes and nice lighting.
Wires and textures will come later.
PS : some chests may look blurry, I think Unreal displayed the wrong mip map, I'll check that.