best script for bevellling+ normal map question
polycount lvl 666
Yeah , trying to do some slightly more techincal stuff. Just thought bevelling edges was the way to go. Any suggestions as to the best script for bevels. Meshtools perhaps?
Also if I buld in my bevels manually, then would I delete them after baking my normal map or is it just not possible to make a right angle look round.
The reason i ask is that i don't really want the pain of building manual bevels if I can get away with a faster method.
Imagine a tv which is basically box, but with round edges.
Ideally I would just have a box( with right angles) as the lowest level, but results have been pretty awful as if you assign a smoothing group of 1 to the whole box, the vertex shading is very poor and messes up the look of the normal map.
Any help would be appreciated:)
Also if I buld in my bevels manually, then would I delete them after baking my normal map or is it just not possible to make a right angle look round.
The reason i ask is that i don't really want the pain of building manual bevels if I can get away with a faster method.
Imagine a tv which is basically box, but with round edges.
Ideally I would just have a box( with right angles) as the lowest level, but results have been pretty awful as if you assign a smoothing group of 1 to the whole box, the vertex shading is very poor and messes up the look of the normal map.
Any help would be appreciated:)
Replies
You shouldnt have any vertex shading problems, because it only apears if you try to give a whole box smoothing group 1.And you never have to do that.
If your bevel is so small that your low-poly can be a box, then that means you can have different smoothing groups for the low-poly faces.
But if your bevel is bigger than that, then it means you have to add more polys to your low poly version, and by doing so you will get rid of the shading issues because of the smoothing group(more poly+1 smoothing group = ok).
So i cant imagine a case where you'd have to create a box as the low poly AND have all its faces on smoothing group 1.
My english is poor i know, so ill try to explain with an image:
from left to right: wireframe low poly,vertex shaded low poly,normal mapped low poly, high poly
Anyways, maybe this isnt what youre asking, in that case im sorry:).
_Oz,thanks for that diagram, very instructive. The only problem is now that in the case of the simple box, when I subdivide it turns in to virtually a sphere( in max BTW). To get around this I turn on separate by smoothing group and then subdivide a few more times.
Unfortunatley when i render the normal map, the hard edge of the low poly gets burnt in also. So i get a normal map that is producing a round edge on top of a box with hard edges. Any way to avoid this apart from going slightly higher poly with a chamfer box?
The reason i got confused was that it seems to be common practice to assign one smoothing group with characters, because they don't tend to have vertex shading issues as they are reasonably high poly these days.
then things are different if you're using tiling textures or trims, in that case, it may be wiser to smartly use hard edges/bevels combinations on the lowpoly to get the round edges where they need to be but also fix the shading errors that the normal map will not fix (since it's not baked in it)
I also tend to place the bevelled edge of a normalmapped trim even on an hardedged model, it tends to soften it slightly, and if you're using baked lighting, that should soften it even more.
if you're using realtime stencil shadows, bevel is the best way, since hard edges will be superobvious, wether they are nicely/uniquely normalmapped or not.
Check this image(this mesh isnt clean at all, was just to show what i mean:).
Oh and it may sometimes be kinda hard to guess where to put edges, in that case you can try dubplicating your model(select reference mode) move it away to the side, throw a turobsmooth on top of the new copy and turn on the subdivision to 2 or 3. This way you can work on your original and see whats happening in real time, no need for switching to subdivision mode(it can be laggy).
In this example I have almost made it work. The smooth edge you see on the left is mapped on to a hard corner. I think it doesn't work on the right because I have separated the uv's along the edge
In your second pic above, would that be your final low res model ie with all the extra edges built in, or would you optimise it again after generating the normal map. I am guessing that if you did optimise it again, it might look wrong.
And about my low poly, i'd create a whole new one,one that matches the high poly and one thats optimized as hell.
_Oz , so your optimized one would still have some bevels on it?
I just just noticed Vahls post about the stencil shadows and yeah now I think about it, even if I managed to fake it using my cheap ass method, it would still look wrong with shadows in game
1 you build in all the extra edges/bevels you need so it will subdivide properly.
2 generate the normal maps using the usual method
3 leave the bevels intact on the final in game low res model, not turn it back in to a right angled box?
man, i often get stuck on the simplest things , then go and solve some other complicated problem:)
Suprore, I had to clarify more than just the bevel issue. i need to keep these assets I am doing fairly low poly, so was trying to find a method to accomodate this. Sometime a day spent researching can save you a lot of time in the long run:]
EDIT Cheers for that _Oz,everyone, i am a lot clearer on stuff now.
Time is money, so don't spend ages trying to figure out a "fast way" if there's already a way which works fine...
Don't bevel or subdivide the box you're baking to, bevel/subdivide/chamfer whatever the highpoly source is. The low-poly shape you're baking to shouldn't need to be edited at all. No chamfers needed.
Vahl hit it on the head when he said if you tried to map a smooth edge on to a low poly right angled box, the stencil shadowing would give it away in game.
The stuff about bevelling was just another issue that i was dealing with.
I probably should have explained it better.
Here is a diagram
The one on the left I would use to make my high poly model and the optimised one on the right I would use for the my bake.
All i wanted to know was could I take the optimised one back to a right angle box without messing up the look of the normal map, but it seems not from what has been posted.
More of an experiment really.
Its kind of sunk in now that its the same as doing characters, the low poly should match as closely as possible to the silhouette of the high, so keeping in those bevels is a good thing anyway.
Thats not a tv BTW, its a suitcase with some robots hiding behind it:/
Anyway I am sorted now, thanks for the help dudes, appreciate it.
I was just having a go at some tech stuff now I have a bit of spare time.