examples of handpainted textures converted to normal maps?

[inlimbo]

i know handpainted normal maps exist and that it's easy to duplicate a base texture and adjust its levels for normal map use, but i don't think i've seen this in practice for the kinds of low-res handpainted characters we'd see in previous generations.

i'm interested in that and specifically examples that look natural in spite of the low-res source. anyone have an example or is anyone willing to put together a quick demo?

 

[inlimbo]

i'll use this image as an example:

the subtle brush-like shadow definition in his face is what i'm looking for. it's uncommon in normal mapped characters due to stark contrasts in lighting and materials

 

[Davros]

I dont think that shadow is due to normal mapping
plus i doubt you would apply it it skin textures
are you gtting mixed up with cell shading ?

XIII


ps: you usually create normal maps using filters in photshop for example
you dont hand paint them with the brush tool

 

[inlimbo]

my last reply was misleading and worded badly, but i posted that image not as an example of normal mapping, but as an example of the kind of hand painted shadow definition i'd like to see replicated in a normal mapped character.

hand painted normals do exist, but that aside, i don't think running that character's textures through photoshop filters or crazybump would be enough. i want to see subtle shadow and specular detail that would probably require more hand tuning.

 

[Xenus]

You mean like this? There are levels of cell shading that go past the crude filter look.

 

[inlimbo]

that looks like flat texture mapping with basic 1D texture lookup cel-shading. i don't want cel-shading as much as i want real normal mapped lighting that captures the brush stroke look i'm going for

 

[Davros]

why do you want it exactly ?
normal maps are to fake extra ploygons not to fake any type of hand painted effect and they certainly dont capture brush strokes
if you want "subtle brush-like shadow definition" then that would be either a texture or a shader not a normal map

i know handpainted normal maps exist

I'm sure somewhere someone has created one, but are they used I doubt it

to do it the artist would have to look at the first pixel and think what part of the model would it map to on the model and what value would it be (and he'd get it wrong)
and do this for every pixel
heres a normal map for a head can you imagine looking at a lit head model and trying to create the normal map by hand and getting it right. it would be an insane amount of work


If you wanted softer lighting the logical thing to do would be to reduce the contrast in an image editor
like so :
(but you'd probably lose detail)

 

[ebola]

the subtle brush-like shadow definition in his face is what i'm looking for. it's uncommon in normal mapped characters due to stark contrasts in lighting and materials

@inlimbo
Are you talking about the shadowing built into the texture where an artist has intuitively simulated Ambient Occlusion. ('brushed shadows').

Seeing this post reminded me of a discussion I was having with a couple of artists about car models back in the Dreamcast era (painted shadows..) vs modern console high poly era (model everything..), and vica versa going to mobile, going back to previous level hardware with the benefit of what we've learned.
I asked them, what's easier to author: - high poly art that you use as source for render-mapped low res+textures (AO, normals maps,specularmaps) or build low-poly, and paint the high detail, as we did back in the olden days.
I don't have a definitive answer ie. tradeoff of quality / time. AO channels also a good guess for specular channels. (raised areas = more specular..)

Looking at old art, it seems to me a lot of the hand-drawing was simulating 'AO' as opposed to directional light - which is why simply old taking color images and inputting into a normal map generator isn't a complete loss as I always thought it would be

I'm intrigued by the idea of 'crowd sourcing' up-res (more pixels + additional layers..) for old games .

@Davros - 'softening the normal map' - is that in effect an 'art-hack' for 'sub-surface scattering' ? (similarly, the 'brushed effects' an artist would intuitively paint into olschool flat textures would be trying to capture some SS effect)

 

[ebola]

<duplicate post sorry>

 

[inlimbo]

@ebola: yeah it's basically AO, but that would require the extra poly detail and non-traditional AO techniques.

@davros: reducing constrast is the logical solution, but that would soften the light uniformly. obviously i don't have hands-on time with normal maps, but i was thinking there must be a way to isolate contrast to parts of the color channel via shader. i just don't know if that would work at all like i imagine in practice. failing that, what about two layers of normal maps?