Need clarification about PBR Rougness+Metalness workflow
polycounter lvl 7
Hello everyone! I need your help.
Sorry for may be lame questions but I'm absolutely new to this PBR concept and quite scared of doing things the way I shouldn't.
So this is my scene of wooden planks in Marmoset. Please have a look at the maps I made and the shader setup.. Here's what I'm striving to learn:
1. Is my Albedo map is correct in sense of "Material Values Chart" for wood material? How do I check if my Albedo is correct for certain material types? How exactly do I have to use those three color swatches given in that chart? I do understand that I have to color pick lets say roughness swatch in that chart and later be aware not to exceed that maximum whiteness drawing my grayscale map in photoshop but how to use Albedo color swatch and what "Reflectivity" color swatch is for?
2. My main material is wood, so what should I do with the default Specular slot in Marmoset's shader? Currently I couldn't think of anything better than just changing "Specular" to "Metallness" slot and just set it to 0..
3. Do you think my Rougness map is ok and the way it should look? I'm concerned because obviously my wood planks look very unrealistically smooth even if I make prominent Normal details - they just start to look like plastic toys with carved wood texture. My roughness map won't help, what am I doing wrong?
4. There's a "Reflection" slot in Marmoset with Horizon Occlusion slider in it. What it really does?
Hope I didn't bore you with my silly questions. Thanks in advance!
Sorry for may be lame questions but I'm absolutely new to this PBR concept and quite scared of doing things the way I shouldn't.
So this is my scene of wooden planks in Marmoset. Please have a look at the maps I made and the shader setup.. Here's what I'm striving to learn:
1. Is my Albedo map is correct in sense of "Material Values Chart" for wood material? How do I check if my Albedo is correct for certain material types? How exactly do I have to use those three color swatches given in that chart? I do understand that I have to color pick lets say roughness swatch in that chart and later be aware not to exceed that maximum whiteness drawing my grayscale map in photoshop but how to use Albedo color swatch and what "Reflectivity" color swatch is for?
2. My main material is wood, so what should I do with the default Specular slot in Marmoset's shader? Currently I couldn't think of anything better than just changing "Specular" to "Metallness" slot and just set it to 0..
3. Do you think my Rougness map is ok and the way it should look? I'm concerned because obviously my wood planks look very unrealistically smooth even if I make prominent Normal details - they just start to look like plastic toys with carved wood texture. My roughness map won't help, what am I doing wrong?
4. There's a "Reflection" slot in Marmoset with Horizon Occlusion slider in it. What it really does?
Hope I didn't bore you with my silly questions. Thanks in advance!
Replies
2. Yes, you should do what you did.
3. Your settings for the mirco-surface layer in Marmoset is wrong, it currently says "Gloss" it should be roughness. For wood, your roughness map is far to dark, with roughness, dark = shiny, white = matte. The roughness of wood can vary quite a bit, depending on the surface... it's is varnished polished wood? It's roughness map will be pretty dark dark. It is dirty rough wood like your's? It'll be closer to white then.
Honestly, roughness is something pretty difficult, I guess the best advice I'd give you is this: start by trying to narrow down the general value of roughness that is correct for the material, then, start thinking about value variations to emphasize the feeling of the material more.
4. I really don't have an answer for you on this one, don't worry too much about it, it's just that when you're dealing with PBR there's no more "specular" it's all reflections.
Sushi - Great tip on inverting trick, it worked!
Thanks a tonn guys!
2) There are two different workflows, spec/gloss and metal/rough. So you have the correct idea using the metallic input since you are using a roughness map.
3) There is no right or wrong Roughness, it is the artists map to put as much detail into it. But you still need to think a bit about what you are doing and what makes sense.
Also don't play with the Horizontal Smoothing slider, leave it at 1.
4) The Reflections drop down is there to let you choose between reflection models, namely GGX( Which is what Unreal 4 uses) and blinn-phong. Its pretty much just a ton of math that does the calculations for how the reflections work.
As far as the horizontal occlusion slider does I haven't the slightest clue, which I'm now curious about.