NORMAL MAPPING for dummies :)

[Anthonie]

Normal Mapping stores light info. sort of. in other words. The normals react to the light and makes the model look like highpolygon. The normal map doesn listen to the normals from the model I think. I think the (custom) normals are stored in the normal map to get allot more light detail than before.

I hope I explained it right and correctly

[newellteapot]

Hi Anthonie!

That sounds good to me...
Is anyone available to write a little simple tutorial or write about the procedure in any software? this thread could become a great resource :

[Anthonie]

well.

Nowadays you can do normal mapping in so many ways.
You can bake normalmaps in max or maya (or other large 3D packages) but you can also export
models to other apps such as zbrush and there bake the normal map or you can even
make normal maps out of normal texures in photoshop.

I could write a tutorial though but don't have time at all. But you can find enough stuff I believe

[newellteapot]

Cheers Anthonie! :)
Anyone has a bit of time to write about normal mapping? A different definition? Tutorials? ideas? Questions?
This is the place for normal mapping galore :)

[[Sanaloria]Snake]

huh ... it seems it doesn't store any light info at all, to me at least, it's just like a bump map : the only infos you have is relief details. The way it's done is interesting : you hae 3 color channels in your picture, R, G and B. their behave like X, Y and Y coordinates of a vector, representing the normal of the surface at a given point. For instance, you have :


-R---G---B-------
128 128 255 => Z+ (pointing from the screen to your nose)
000 000 255 => Z- (from your nose)
255 128 128 => X- (to the left)
000 128 128 => X+ (right)
128 255 128 => Y+
128 000 128 => Y-


This will alter the way the light behave on the object's surface when you render it, but it doesn't store light info (to make things clear). Lihgt info may be stored in a lightmap or in an HDRI map.


If you want more details about the 3 different kinds of normal maps you can have, read the following ;) :


- World space is a map regarding the world coordinates, this means if you rotate the object in your world (your scene), the shading of its surfaces will NOT change ! because the normals are said to be always turned to the same direction because of the world space normal map.


- Object space is nearly the same. In fact you are actually allowed to rotate the object but NOT TO DEFORM IT (with bones for example, or displacement maps), or you will get shading bugs (the same as above).


- Tangent space is the better of all, even if it needs some additionnal CPU time (but not much). You can move, rotate and deform the object as you wish. Note the main color of tangent space is blue because 128 128 255 is orthogonal to your surface (it's your triangle's normal).


If you need tutorials, look inside the Application Specific forums, there may be interesting stuff there.

[Ghostscape]

http://www.poopinmymouth.com/tutorial/normal_workflow.htm
That explains the workflow in Max. There are a lot of other tutorials if you google for this, and there is a big giant thread in the WIP Game Art forum about this already.

Do you know what a normal is? A normal map is simple a RGB representation of the normals, so that you can have normals on a per pixel basis instead of a per face or per vertex basis.

A normal is a normalized (means the values add up to 1) vector (a direction + intensity) that describes the direction the face or vertex (or with a normal map, a pixel) is facing. It is functionally a little arrow sticking perpendicular to the surface. If your palm was a face, it's face normal would come directly out of it, like if you were balancing a pole on your hand.

Lighting in a 3d world is calculated by comparing the angle of the light to the normal. So if you had a normal facing away from the light, it would be dark, and if you had a normal facing towards the light, it would be bright.

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