Normal map smoothing groups problem
Hello, Sorry for the generic title, I too have looked through far to many normal map problem posts and its been something simple like not splitting the uvws by the smoothing groups. However I seem to have done something odd.
I made an object with was a rectangular box bashed up. the lowpoly for it was just a rectangular box. It was made using a copy of the HP with the modifiers taken off.
On the LP i set different smoothing groups for each side and split the uvs.
I rendered it out with the RRT inside of max
when i came to look at the normal map on the LP, the edges seem fine apart from the ones touching the top face. after changing SG and re-baking a few times i tried removing the SG from the LP with the normal map on it. this give me the look i wanted. all the edges looked fine.
so why was it displaying wrong with the Smoothing Groups setup but right when i took them off the sides?
What i ended up doing was rebuilding the box and baking it again. This time it worked with Smoothing Groups.
as you can see here, this is what it looked like with Xoliulshader. also the bumps on the box don't stick out/in as much as the others
I then went and tried it with max's own bump display
And this shows some odd plane on the side of the box.
if i go in and move a vert on that box it becomes right. here's a video:
http://wireframebox.com/linkto/3ds/oddbox_sg.wmv
So this time the issue is not with the normal map but with the geometry.
I couldn't find out what it was so here is a scene file if any of you want to look
http://wireframebox.com/linkto/3ds/oddbox_sg_problems.rar
The first 2 lp's have the same map and the right one has a different one as its a different box.
While re-making a box didn't take long, i'd rather find out why this happened so it wont happen again. maybe people here have had odd errors along some edges on a bigger piece and never solved the problems. they just put it down to a bake error.
This is not something I've seen on her or any site before. whats it doing?
-lloyd
I made an object with was a rectangular box bashed up. the lowpoly for it was just a rectangular box. It was made using a copy of the HP with the modifiers taken off.
On the LP i set different smoothing groups for each side and split the uvs.
I rendered it out with the RRT inside of max
when i came to look at the normal map on the LP, the edges seem fine apart from the ones touching the top face. after changing SG and re-baking a few times i tried removing the SG from the LP with the normal map on it. this give me the look i wanted. all the edges looked fine.
so why was it displaying wrong with the Smoothing Groups setup but right when i took them off the sides?
What i ended up doing was rebuilding the box and baking it again. This time it worked with Smoothing Groups.
as you can see here, this is what it looked like with Xoliulshader. also the bumps on the box don't stick out/in as much as the others
I then went and tried it with max's own bump display
And this shows some odd plane on the side of the box.
if i go in and move a vert on that box it becomes right. here's a video:
http://wireframebox.com/linkto/3ds/oddbox_sg.wmv
So this time the issue is not with the normal map but with the geometry.
I couldn't find out what it was so here is a scene file if any of you want to look
http://wireframebox.com/linkto/3ds/oddbox_sg_problems.rar
The first 2 lp's have the same map and the right one has a different one as its a different box.
While re-making a box didn't take long, i'd rather find out why this happened so it wont happen again. maybe people here have had odd errors along some edges on a bigger piece and never solved the problems. they just put it down to a bake error.
This is not something I've seen on her or any site before. whats it doing?
-lloyd
Replies
it came out ok when i made a new box but that's not solving the issue.
here's me adding an extra edge,
Seems like it kinda pushs the odd section into the mesh :S
there's not extra geometry there tho
heres the uv with that extra edge added
it is also happening on the other side
all the faces are split. they are split because each face has a different SG. i thought that's how you uv'd things with SG's. split islands :S
You cant either export the mesh as an obj without normals and re import it, or you add smooth modifier on top of the stack and it will re calculate them.
Both remove the artifact for me. The only reason i mention the export method is sometimes its been a last resort for me when odd things are happening and nothing else works.
Im sure there is a ninja way of fixing the issue but this works
However exporting it out without normals then importing it back and setting the SG seems to work!
so if this happened again I'll do that.
Thanks. That's one of the things i didn't think of
-lloyd
Looks like its still happening
A. Normal maps need to be rebaked any time your mesh normals(hard edges, smooth groups, whatever) are changed, so you can not apply hard edges, bake, and then remove them, or visa versa, as they are reliant on your mesh normals.
B. You're getting artifacts because you have hard edges that share the same uv edge. Whenever you have hard edges, you also need to split up and move apart your uvs, or you will get these "seam" type artifacts.
A, Yeah i know this. but the mesh came out with bad looking edges, once i took the SG off it, it looked how it should. that's why it was an issue :S That shouldn't be happening.
B. The edges are split. that's why there's a problem. Its being odd. I got around it be exporting this mesh and reimporting it without normals. that wouldn't work if the edges were joined in the UVW as the UVW wouldn't change.
It appears like the uvw positions jump when the SGs are set and when i take them off they sort themselves out.