how to make a hard surface normal map

onrew

in this link
http://www.iddevnet.com/quake4/ArtReference_CreatingTextures
there is a hard face normal map, the high polygon mesh include different part , and like this type of normal map ,how to bake it in maya? combine it or use boolin or something? THX

Eric Chadwick

[ QUOTE ]
Texture Modeling Tips:
...
2. Float Parts and Pieces: Be sure to “float” model parts and pieces. It’ll lessen the poly count on your texture and make it easier to model.


[/ QUOTE ]

I'm not a Maya guy, but I think the instructions make it clear that you don't boolean nor do you combine the meshes. The normal map projection tool (not sure what Maya's is called, do a search) will ignore the distances, combining the meshes for you. This method works the same in most 3D apps.

Xnormal is a great normalmap baker, if you haven't tried it.
http://www.xnormal.net/

Joseph Silverman

http://boards.polycount.net/showflat.php?Cat=0&Number=211925&an=0&page=2#Post211925 !

Eric Chadwick

When is all that great info gonna be distilled down?

I tried, posters didn't like the idea of me repurposing their content into Rick's wiki. Woulda made some good linkage though.

Maybe a sticky is the best we can do.

onrew

THX GUYS!and if I have a high poly character model with a lot of details with different part in his cloth,belt,gear,
ect.like a model used in a film.can I bake normal map to only one mesh?

Sage

Yes. You'll find once you start baking normal maps it will bake any poly that's near enough even if you don't want it. You'll have to compensate for this by moving the unwanted polys away from each other. So if you have 3DS max you can apply an edit poly to your low and high poly while both are selected and then move the parts of the object around so only the parts that need to be touching each other are on top of each other. If this doesn't make sense to you then, just try baking things a few times and you'll see why sometimes you'll have to move things around. Eric if you are willing I can supply you with a simple prop to cover how to deal with normal maps. And no it won't be a grate, it would be a realistic light post. I hope to have that done today. It be nice if the normal map thread started by Per128 was made sticky since that was the whole point of it in the first place.

Alex

Eric Chadwick

Thanks Sage, though by "content" I meant people's tips/tricks. I think the basic deal is people don't want their hard-earned knowledge sitting on someone else's personal site. Polycount's wiki coulda been a good place for it, but it doesn't work. CGTalk's wiki is easy to use though.

Sorry for hijaacking your thread onrew, good luck with it, and keep the questions coming.

Sage

Eric I assumed thats what you meant. I'm making props and scenes for my reel and figured I would share what I learned from the experience. I figured you could add some insight of your own if you have the time. Part of the reason so many of threads show up is because the content created on many sites doesn't show up on web searches. It also doesn't help that the search feature on Polycount doesn't work well anymore like it used to before the site went down.

Onrew sorry for derailing your thread. Ask whatever you want, that's how people learn. What bugs me is when people post replies like, it's been asked before and don't say where to find the information or maybe the post that has the information isn't enough to answer the question.

Later.

Alex

Flewda

I'm not sure if anyone covered this, but I think that method (of having the different parts really far away from eachother) is not the best approach to this. If you do that, you will receive little to no ambient occlusion information from that geometry. And AO can be as important as the normal map (IMO). If the objects aren't close enough, the light/bounces won't affect them the same way it would if they were built right on top of eachother, thus, no AO.

Neox

well you could create AO with crazybumps fake method, works pretty fine for most cases

Sage

Flewda, you can make a copy of your object, one for the normals bake for example and one for the AO if needed. I always keep a copy of the object I use for baking and one for the low poly. And the same for the hi poly if they are going to be at different places. With Max it's easy you just turn off the edit poly modifier and it pops back into place. Also if you use floating geo you need to do something to compensate for the fact that you are using them when baking AO at times anyway. How do you do your normal mapping process? Nice site by the way.

Alex

Flewda

Thanks

I try not to use floating polys for for any sort of concave piece. I will float pieces that extrude out til I am blue in the face (like rivits/bolts, etc). But all in all I try to make everything concave one mesh (per element, not an entire object necessarily). I feel that the results are really nice when I do it this way. It may not be so bad to do it the other way when you are just baking a wall panel, or another tiling piece, but when I am creating a high res prop or whatnot, I like to keep everything together as it would be in reality.

Sage

Onrew Cholden has a tutorial on his site that covers normal mapping in Maya. Here is the link. Hope this helps.

http://chrisholden.net/tutor/tutors.htm


Flewda, I guess my work flow is very similar to yours. I avoid floating intrusions as well. Sometimes I just bake them to a plain and layer them in photoshop, or with crazybump.

Alex

onrew

THX, there are great, and I have some test about the RGB channal ,but I don't know how is B channal work in a normal map,say 2 different noraml map have the different x y (R G)normal dirction,these two information determine the face's shodows but why we need a B channal,?

Panupat

Well I think it's not that you *need* Blue channel, but it's just there in every image file formats. Unless you can name me 1 format that only has R and G and no B... or greyscales.

The blue channel is good tho. Try fill it with white and it can get really hard to see what's going on with the normal maps.

Sage

I believe the blue channel in the normal maps stores the height or up direction information of the normal.

Alex

onrew

yes I learn it form some documents,so I make 2 mesh ,one is heigher than the other one , but they have the same X Y normal dirction,and the different between these two map is the size of area , but the same gray in RGB.
and B channal means we can control the the gray of shodows,that's usefull in deal with seam