Normal Map Tutorial - High Def Normal at Low Poly Models

[Deedlit]

I just read that and belive founded amazing to help create complex models just using normal maps and using low poly count models, i know most of you guys already know that, but for me a begginer at 3ds max helped alot, hope you guys like.

Im not owner / tutor / creator of that, its just a simple link if owner (christopher albeluhn) wanna i remove from here lemme know.

http://www.chrisalbeluhn.com/Normal_Map_Tutorial.html

[blindmankind]

i do not get it, my normal map is only purple and not rainbow

what i am doing wrong?

[thatTESguy]

i do not get it, my normal map is only purple and not rainbow

what i am doing wrong?

 

Object or tangent normals?

 

A tangent normal map look like this:

 

An object normal map looks like this:

 

 

See http://wiki.polycount.com/NormalMap/ for an explanation.

[blindmankind]

i get only the tangent normal map, but i want the object normal map

how can i make it with photoshop?

 

[gerra6]

i get only the tangent normal map, but i want the object normal map

how can i make it with photoshop?

It's not really something you can do in Photoshop, at least, not really.

 

This sort of normal map needs to be baked in a 3D program like Blender, Max, Maya, etc.

 

The basic idea is that you start with a very high poly model, one like all of those crazy mods that waste 30,000 verts on a pair of stockings.

 

Then you bake all of that crazy geometry data into one of two types of high resolution normal maps.

 

Here's the general rule of thumb:

 

If you are baking a normal map for a non-deformable object, generate an 'Object Space' normal map. That's the rainbow looking normal map.

 

If you are baking a normal map for a deformable object (like clothing, skin, etc), generate a 'Tangent Space' normal map.

 

Basically, you start with a high resolution model and a low resolution version of the same model (use appropriate techniques to drastically reduce the vertex count of the model - generally a combination of scripts and sculpting).

 

Then you bake the high resolution model onto the low resolution model to generate your normal map (the actual techniques vary depending on the tool and the program).

 

The high resolution normal maps will give your low resolution model the illusion of high resolution detail. Which is a lesson many modders on the Nexus sorely need to learn. (Speaking as a modder who primarily writes tools for other modders to use.)

[Deedlit]

Agree with gerra6, and about the "Which is a lesson many modders on the Nexus sorely need to learn." belive very truth that, lost count of how many "armors" mod i deactived because that make game very unstable.

[blindmankind]

hm, "If you are baking a normal map for a deformable object (like clothing, skin, etc), generate a 'Tangent Space' normal map"

but why there are allways the object map for a skin?

so i can use a tangent map on a skin, or is tangent space map another thing? ;o

 

sorry for my bad english, i do not understand much^^

[gerra6]

Compare the rainbow looking normal map to the mostly purple normal map.

 

do you see those 'hard' edges between colors in the rainbow normal map. Those basically define some fairly drastic differences in the way the shading on the mesh will be rendered from one side of the object to the other.

 

If you generate an object normal map for something that is highly deformable, those hard edges in the normal map end up giving invalid information about the structure of the mesh to whatever is rendering that object.

 

Now...I don't know much about Skyrim normal maps specifically...I know that Skyrim skin meshes use several different types of maps, but I haven't really looked at what they are. So it's possible that Skyrim uses object normal maps for skin...no idea. It doesn't seem like a good idea to me unless they wrote their shaders expecting exactly that.

[FastestDogInTheDistrict]

The high resolution normal maps will give your low resolution model the illusion of high resolution detail. Which is a lesson many modders on the Nexus sorely need to learn. (Speaking as a modder who primarily writes tools for other modders to use.)

 

 

*guilty as charged*

 

I normally address this by adding more vertices, & thus making the mesh higher-poly. Can this normal map method add smooth curves to a mesh where there are only jagged edges? Eg: the Vanilla Wolf Armour mesh, which is VERY low-poly, does not lend itself well to conversion for curvier bodies like SeveNBase.

[Deedlit]

 

The high resolution normal maps will give your low resolution model the illusion of high resolution detail. Which is a lesson many modders on the Nexus sorely need to learn. (Speaking as a modder who primarily writes tools for other modders to use.)

 

 

*guilty as charged*

 

I normally address this by adding more vertices, & thus making the mesh higher-poly. Can this normal map method add smooth curves to a mesh where there are only jagged edges? Eg: the Vanilla Wolf Armour mesh, which is VERY low-poly, does not lend itself well to conversion for curvier bodies like SeveNBase.

 

Good point, never tested that, but in theory yes, all depends the high poly model you made the texture, keep in mind will not be really like high poly, but will get similar.

[gerra6]

I normally address this by adding more vertices, & thus making the mesh higher-poly. Can this normal map method add smooth curves to a mesh where there are only jagged edges? Eg: the Vanilla Wolf Armour mesh, which is VERY low-poly, does not lend itself well to conversion for curvier bodies like SeveNBase.

Well, adding a few vertices here and there can be necessary at times, particularly if you are attempting to modify a piece of armor to match a different body style, such as with the Clothing Bodystyle Converter

 

On the other hand, I get lots of PM's from folks who attempt to run 300,000 face nifs with 27 geometry blocks and 7 scene roots through my tools and wonder why things start to choke. Sure, the end result is that I refactor my code to be more robust and most of my tools automatically spot and clean bad nifs now, but it's an ugly road.

 

Anyways:

 

Extra vertices to help clothing and armor better match the body style nif: Good (but try clothing converter first)

Extra vertices to improve *noticeable* curves: Mostly Good

Non-Visible vertices: BAD

Extra vertices that add no real detail: BAD EVIL BAD

Socks with 170,000 Triangle Points: DIE IN FIRE.

 

BTW...not kidding about the socks. Check it out.wa5.nif

 

Now...maybe they're the most amazing socks on the planet. Maybe they deserve more resources than a half dozen dragons. I dunno.

 

Me...I'd make a 600 poly version (if that) and bake a normal map.

[FastestDogInTheDistrict]

300,000 face nifs with 27 geometry blocks and 7 scene roots

 

*guilty as charged*

 

Now I feel REALLY bad about the Dawnguard meshes I'm working on this weekend!

 

 

... and those socks NEED TO DIE! A 28466 vertice, game-melting, 3dsMax-traumatising, sock-shaped monkey wrench. Also - they're weirdly lumpy. Where on earth did THOSE come from?

[gerra6]

No idea where they originally came from.

 

I first received them in a PM asking why my tool kept crashing.

[blindmankind]

me thanks for try to help me, but i do not get it^^

i use my paintskill and mod a bit the existing map ;]

[Deedlit]

No idea where they originally came from.

 

I first received them in a PM asking why my tool kept crashing.

lol the funny is the "asking why my tool kept crashing" lol and he/she asked why lol.

[thatTESguy]

 

300,000 face nifs with 27 geometry blocks and 7 scene roots

 

*guilty as charged*

 

Now I feel REALLY bad about the Dawnguard meshes I'm working on this weekend!

 

 

... and those socks NEED TO DIE! A 28466 vertice, game-melting, 3dsMax-traumatising, sock-shaped monkey wrench. Also - they're weirdly lumpy. Where on earth did THOSE come from?

 

 

Surprisingly though, skyrim can handle face-melting amounts of vertices fairly well - it's the 4K diffuse/normal/specular maps (fill rate) that is somewhat more punishing for performance. I will admit to testing bodies with something like 100-150K verts (again, nothing that I'll ever think about releasing publicly), and the frame rate impact for 2 characters with that body is something like ... 0.5-1 FPS lower. On a 6950 (not exactly a new card these days). (that said, the verts were used for some horribly complex organic shapes that deserved that sort of vert count - not flat stuff like the link above).

 

 

 

 

 

 

I can sort of tolerate vert use like that. I can't tolerate texture use where someone uses something like 5% of a 4k x 4k texture, or (god forbid) includes a 1024x1024 texture of solid black/white. (no texture detail, no alpha, nothing. Oh, it's also invariably saved at DXT5 or something with a completely useless, white alpha map).

 

A lot also depends on what the verts will be used for. Are those socks going to be only on the main player/companions? If so, probably not that big of a problem. Will someone use them to create an army of a few dozen poorly textured furries and put a fight outside Windhelm? That ... may be a problem.

 

[thatTESguy]

To answer the OP questions though:

 

Skyrim uses object (model space) normal maps for body data, including face, hands and feet. Tangent for everything else. This is controlled via a simple flag in the NIF file; if you want object space armors or tangent space bodies, you can make that yourself. I still don't have a good explanation of why skyrim uses object normals for bodies besides "no seams", which you can also achieve with tangent normals, at least technically. Some forums at least suggest that object normals might be faster, which is nice, but almost irrelevant for most purposes.

 

You can convert between the two if you have your low poly mesh, and XNormal, which offers a conversion option. No 3ds max, blender, whatnot required (except to generate the initial model file from the NIF for XNormal to read)

 

PS http://docs.cryengine.com/display/SDKDOC4/Tangent+Space+Normal+Mapping ... object space normals might allow for a bit more laziness in aligning normals along seams / meshes - they will look "seamless" even if the normals aren't perfectly aligned.

[Deedlit]

@bllindmankind , i hope that can helps with your doubt : creating normal maps i just pointed that right page because looks like you got a problem with that.