Bevel / Chamfer Edges vs Normal Map Bake

VanessaCeline

Hey guys, in your opinion, what is better: Beveling edges directly or baking a high poly with beveled edges onto the low poly? I'm trying to figure out what would be better also from an optimization point of view, but also visually. Apparently, one bevel is the same as splitting the uv s for normal baking, at the same time with baking you could make it look similar to multiple bevels. But then, what if you want to use tileable textures? With some objectswouldn't that be a bit of a pain combined with normal baking (if that's even possible)? 

tynew

When an object has a large enough bevel IRL you'd want to bevel the geometry. Depending on how close the object is viewed in-game, you want to maintain the silhouette. If you have some large objects, such as long vertical pillars/walls, you'd typically want to bevel this. Whereas compared to something small like a tissue box on a desk it would not be required. 

It also comes down to the budgets and requirements of your game and system (mobile etc.) Having LODs and UVing beveled meshes can be a tedious process. If you do bake high res AND use tileable textures, the UVs will just be split along a seam along one of the beveled edges, most likely the edge that has the lowest visibility towards the player. Most of the time for current spec environment pieces, all large corners/edges are beveled and the normal map is only used for micro details and decals. 

VanessaCeline

@tynew That's really good info! I have a big individual project going on right now for university and I've been wondering for some time how to approach it. I'm am trying to go more towards realism, so I think having directly beveling geometry might also help with that. 

icegodofhungary

If I'm understanding everything correctly, your environment pieces would use actual bevels. You can fake bevels with trim textures as well, but those aren't baked unique to the object. You usually save the unique baking for props. Unique UVs for large environments is too time consuming and requires too much texture memory.

VanessaCeline

@icegodofhungary Let's say I have, for example, a street lamp of 6 meters with a lot of edges that need bevelling. How would you approach this? Initially I did this with a bake, but if there's a way to save time while maintaining quality and optimization I'm up to it. Do you think trim textures would work for that? At the very least, I could straighten the UV Edges so that they fit the trim texture I suppose? I never used trim textures but I've heard about them, I would have to do some research before to see how I could get bevelled edges on a trim. 

icegodofhungary

I'm super biased because I love trim textures but you can use them for pretty much anything, so I would definitely try to make my street lamps using a small trim sheet. I would say that a street lamp isn't important enough to spend a lot of time on or do a full unique UV bake with zbrush sculpt. Unless it's a very important street lamp. This is also a good reason to use trims instead.

https://www.youtube.com/watch?v=IziIY674NAw

https://www.youtube.com/watch?v=DipfrjCgYW8&list=PLBi3xvwvY3dk09fNSd7jrnEscXS_6_1p2

https://www.gdcvault.com/play/1022323/The-Ultimate-Trim-Texturing-Techniques

http://twvideo01.ubm-us.net/o1/vault/gdc2015/presentations/Olsen_Morten_TheUltimateTrim.pdf

https://www.artstation.com/artwork/1eREK

If the bevel needed is large enough, I would just use a geometry bevel. You could also use a combination of trims and tiling textures. They're not mutually exclusive. You could also use a combination of unique UVs and trim UVs and tiling textures. Though you want to keep the amount of materials low for each object, so I probably would just use a trim alone.

VanessaCeline

@icegodofhungary

I am trying to get somewhere on the line of realism / photorealism, i've actually seen that god of war uses trim sheets as well now that i think about it, so that should be fine :-? Thanks a lot for the resources btw! I might actually use this for my project! 

How do you combine trims and tiling textures btw? Right now I use Unity HDRP, they have a layered material option but I don't know how good that'd be for optimization.

Oh, and another question: If let's say, i have a lot of ornaments for different objects, would you use trim textures, or decals? Or maybe something else?

icegodofhungary

Apply trims to the parts of your mesh that need it, apply tiling to the parts that need it. Multiple materials per object. I say it would depend on the ornaments. If you look in the artstation example I posted, the person creates some unique metal meshes out of trim and then uses them as modular pieces to create things that a plain trim texture couldn't. But yeah, you can still use decals over trim stuff too.

VanessaCeline

@icegodofhungary Nice! Hope I'll get the hang of it soon then. Would save a lot of time once I learned it.