A question on Bevelled Edges, Normals and UV Mapping
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Hey all, Been meaning to join up here for ages now! Such a great place!
So I do environment art and Materials and am really keen on building my skills and techniques. I really like the world of Deus Ex, and so I am building a similar, cyberpunk environment in unreal 4. I've been using texture sheets for trims and those kind of details, as mentioned in this fantastic post, however I was last night reading an interview about the making of mankind divided and I came across this titbit of info:
"For bevelled edge, we actually break the vertex normal. We cannot afford texture memory to map the bevel’s normal unto the texture, so we build a tool that defines which bevels you want to have a nicely bent bevel normals on. This tool remembers all of the bevels on any given mesh in max, and it remembers them forever, you can give a solid beating to a mesh and the “bevels” are still located in the tools memory, coherently. This is important because breaking vertex normal is risky as any modification to a mesh generally modifies the normal greatly. Instead, we remember what we want to be bevelled, and we automatically reprocess these normal every time we export. This does cost a bit of vertex memory, but we save a lot by not putting this information into textures."
I am wondering exactly what that means or how to go about it? I've edited vertex normals in max before, so I know what they are, just don't understand exactly what he's saying here. So my understanding is they are able to make un-bevelled edges into bevelled ones, similar to when baking or using a texture sheet, except it's stored in the mesh, and not part of the texture sheet! So it might be similar to face weighted normals?
Sounds super useful, so if anyone has any help going about this, it would be great as unwrapping the geometry to a sheet takes forever!
Thanks in advance!
So I do environment art and Materials and am really keen on building my skills and techniques. I really like the world of Deus Ex, and so I am building a similar, cyberpunk environment in unreal 4. I've been using texture sheets for trims and those kind of details, as mentioned in this fantastic post, however I was last night reading an interview about the making of mankind divided and I came across this titbit of info:
"For bevelled edge, we actually break the vertex normal. We cannot afford texture memory to map the bevel’s normal unto the texture, so we build a tool that defines which bevels you want to have a nicely bent bevel normals on. This tool remembers all of the bevels on any given mesh in max, and it remembers them forever, you can give a solid beating to a mesh and the “bevels” are still located in the tools memory, coherently. This is important because breaking vertex normal is risky as any modification to a mesh generally modifies the normal greatly. Instead, we remember what we want to be bevelled, and we automatically reprocess these normal every time we export. This does cost a bit of vertex memory, but we save a lot by not putting this information into textures."
I am wondering exactly what that means or how to go about it? I've edited vertex normals in max before, so I know what they are, just don't understand exactly what he's saying here. So my understanding is they are able to make un-bevelled edges into bevelled ones, similar to when baking or using a texture sheet, except it's stored in the mesh, and not part of the texture sheet! So it might be similar to face weighted normals?
Sounds super useful, so if anyone has any help going about this, it would be great as unwrapping the geometry to a sheet takes forever!
Thanks in advance!
Replies
In the red highlighted areas we have bevel details that I would have assumed were fakes by a normal map, however, the environment is NOT baked and he said specifically that they didn't use a texture to do that, what they used was a technique involving splitting normals and using some kind of script to to create these details. So what I'm asking is what you think this tool of theirs is doing and how it all comes together to create these details! Hope thats a bit clearer!
If I'm mistaken and some of them are smoothed (even though there are visible hard edges on some of the screenshots) they are probably talking about face weighted normals:
https://polycount.com/discussion/154664/a-short-explanation-about-custom-vertex-normals-tutorial/p1
Edit - I checked out the article once again and I'm pretty sure its simple beveled hard edges.