specular maps and normal maps

[animatr]

have some procedural questions about spec maps and normal maps. First of all, spec maps: what's the best way of creating a specular map? What are some tips and tricks and what not that make great spec maps? I know what a specular map does, but i have seen many specular maps that i look at and not sure they look like they do. Poop has one for his skateboarder on his website that particular interests me.

And for normal maps: What's the best way to get your spec map to really bring out that normal map? What normal map generation program do most of you use? (i have been using max's projection mapping, but not too happy with the results. I tried using Melody, but I was getting strange results just trying to do a projection like in max)

and most importantly, what's the best way to paint your diffuse for your normal map? do you paint over the normal map? is there a better method?

Thanks for your time!

Jeremy

[Eric Chadwick]

I like to generate a heightmap at the same time I generate a normal map, which I find works great as an overlay or multiply layer on top of the specular, so the specular doesn't show in the deep cracks. If the heightmap doesn't look good, I'll generate an ambient occlusion map (AO) instead.

I also like to multiply this on top of the diffuse map at 75% or less, depending. Adding a little AO is good, since real-time lighting usually doesn't include good AO (it is starting to be used though). Also provides a guide for color location.

Specular maps... I just try to think like shininess. /images/graemlins/smile.gif Where would I be glossy, where not? If I am shiny, why am I? Wet? Smooth? Greasy? This helps me determine the color to use and where to put it.

I find it helps sometimes to use a hue for the specular that's 180º or 120º from my color map hue, but subdued. Adds richness because it tends to desaturate the color mmap underneath the specular highlight, which then causes the rest of the texture to look more saturated. That's why you'll see people using purple or blue for the flesh tone specular, because it's a kind of hack to get a sub-surface-scatter kind of look to the sides of the specular.

Pior has a great tutorial (http://pioroberson.com/tuts/tut_texturing_tricks.htm) that includes how to generate a specular, though for me painting is generally better/faster.

Helps me to reinforce the specular with bump detail. I just did a Medeival stone wall with drippy green slime running over the stones... the normal map gives the slime a slightly-raised edge, the diffuse makes it a bit green, and the specular uses a light orangish color.

I find it's good to use a full range of value for every map... thresholding a map to solid-ish colors reduces the richness of the texture. Holds true for color maps, specular maps, AO maps, etc. Specular color maps in most engines need to be fairly dark, but within that range you'll get better results with variation, instead of just solid areas of color.

We had a good discussion about specular color and lighting awhile back, might be a good read. I used to use the nick "posm"...
http://dynamic.gamespy.com/~polycount/ubb/Forum8/HTML/004130.html?00037


Whew. Typing this out is good for me, helps me think.

[Daz]

Hey animatr, I have some thoughts about creating specular maps here: http://www.3dm3.com/tutorials/maya/character/index6.php

[Eric Chadwick]

Hey Daz, what's the reasoning behind painting the pores as bright dots? I'd think you would want the inverse... dark inside the pores, light on the rims all around them, so the specular stays outside. When I look closeup at my own face, the insides of the pores shine the least. (or maybe I just need a good scrubbing)

[Daz]

Well, I guess it depends how you visually read the image as to wether or not you see the white as dots. I kinda see it more as the black is breaking up the white. But I dunno. It's really whatever works that counts. Im sure you could come up with a much better representation of a skin pattern. I don't actually use this one anymore, but If I posted what I do use, I'd be giving it all away! /images/graemlins/smile.gif This was about principles really, as opposed to the Art assets themselves.

[animatr]

wow. thanks for the great info guys and all for the awesome links. learned tons of stuff. Makes me want to go back and redo some of my older stuff:) thanks again! If anyone has anymore tips and tricks, spread the joy!

[CheeseOnToast]

Hey Daz...do you know any way to make spec maps show up in real time, in Maya's high quality display mode? I can change a Blinn shader's specular roll off and eccentricity with the sliders and these changes will be shown fine, but as soon as I plug in a texture it no longer displays. Any thoughts?

[Eric Chadwick]

Well Daz, the result turned out great. That's all that matters! Did you use any color in his spec map, or was it purely an intensity map?

On the same site as Daz's tutorial, there's also an old tutorial from J-J-J Mortimer. He has some info about specular color, though it looks like he used two maps as combo specular and reflection passes. Not much meat there in terms of info, but he did offer some nice large example images.
http://www.3dm3.com/tutorials/maya/texturing/index6.php

[Eric Chadwick]

Hey CheeseOnToast, I wonder if you could adapt Ben Cloward's excellent HLSL shaders for use in Maya? He supports real-time specular, etc. They're written for use in Max, but I would imagine Maya would somehow support these shaders as well...
http://www.monitorstudios.com/bcloward/resources.html

[Daz]

Haha, I just reread my own line which explains a few things:

"Specular map 1 ) To be really clever here, we should probably use the same base texture pattern for skin colour base, skin bump and skin spec in terms of its patterning of skin pores. For some bizzare reason that I can't recall, I didn't in this case, but I think you'd have to be a pretty astute observer to notice. So starting from scratch, or from an existing base map you've made, create a pattern that looks somewhat like skin pores. "

That'll make you the astute observer then Eric ;-p

For skin I usually just use the stahlberg ramp method of tinting it blue to counteract the tendency for it to yellow when hi-lighted.

CheeseOnToast: the weird thing about that is, at work we use the high quality display mode for normal maps, and some of us can get it to work, and some of us cant. I personally cant, and I think it's due to an aging grafx card. But the ones that can get the normal map showing in the viewport fine, just slot the spec in the spec colour and it just works!

[PaK]

worthy to be sticky imo

[Eric Chadwick]

Hahha Daz, not so astute if I didn't actually absorb your words the first time. Good tutorial, especially (for me) the image-reference section.

I still don't understand the yellow-tendency thing. Per had a good point, in that other thread:
-Specular is additive, and adding grey to anything retains the existing saturation.
-If you want less saturation in the highlights, the specular map needs to be the opposite colour of the diffuse.

I wonder if the yellowish highlight tint is because the skin color is (for caucasians) mostly tan already, and the white light is simply brightening the colormap.

But when I look at a photo of someone in the sun (my son last summer), I don't see a yellow tendency.
http://www.ericchadwick.com/examples/images/20050704jason.jpg
What I see is the skin generally turning red right next to the light/shadow terminus, like under his cheeks and eyebrows. For me this is what makes skin come alive or not.

So, if I'm thinking correct, using a bluish specular color seems to help solely because it desaturates the lit side, allowing the terminus to be more saturated, simulating SSS.


I dunno, I'm still kind of confused about the colored specular thing. I'm thinking it mostly works this way because of our primitive lighting/rendering tools. I should probably have some 3D examples here instead of photos.

[Daz]

Well, I guess I took mr. Stahlbergs word for it without really questioning it. I think you're right in your assessment of how the principle came about. It was all born from his attempt at vague SSS in the maya software renderer, so the desaturation could well be an attempt to bring out the red near the terminus.
I've actually found that the blue-hi-lights thing works better in renders attempting to be outside, and I think that's because Im assuming that a very bright hi-light would be bouncing off a surface that is somewhat reflective and hence have some sky colour in it perhaps?

[MoP]

Yep, I think Daz is right about the blue thing - if a subject was indoors and lit differently, blue might not be the best choice - it seems to work best for outside renders because the sky tends to tint a lot of things bluish on a sunny day.

[sinistergfx]

Well, that really depends on how blue you make it. Mainly the blue is to oppose the color of the skin so you get desaturated highlights. Helps you get away from the usual plastic-y look of cg.

[Eric Chadwick]

OK that's what I thought. It seems to be a quickie to counteract our lack of rendering power. I see what you all are saying about the blue "northern light" part of outside lighting.

We have something in the pipe here that might help out with this, but it'll likely incur multiple passes. The idea is to dynamically generate a mask between two materials, based on the light angle (or others), with some additional controls for the gradient. Should be cool...

[perna]

ok guys, my 2 pesetas, quickly
specular is reflection of strong light source(sun)
ambient light is reflection of global light(sky)
materials have different properties of reflection. Clay has wide and desaturated highlights. Smooth plastic has saturated and sharp highlights.

There's a lot to be said about the physics of light and the reflective properties of materials, maybe I should write a doc finally

[perna]

oh, yes so the point: use blue in skin specular maps still indoors. there's no difference. The blue is there to describe the nature of the material, not the external light sources.
[edit]: EricChadwick, everything hit by sunlight in that photo is drenched in yellow, the grass, the trees, the skin. Shadowy areas are influenced mostly by the ambient sky color, like the house. Now check out the strong highlights on your sons skin, they're almost grey. Very desaturated.
The red skin in the shadowy areas is because you're not seeing light hitting skin directly there, but light as it has traveled through flesh and been stripped and now consists only of red wavelengths

[Keg]

http://www.itchy-animation.co.uk/tutorials/light01.htm

Set of tutorials talking about the properties of light. might be useful for some

[Eric Chadwick]

Yeah, that's a good review Keg. Another here (http://itchstudios.com/psg/art_tut.htm), from a painter's perspective. You've probably seen it.

Hmmm, Per I'll have to disagree with you that the sunlight is yellow in this shot. The shiny wet parts look white to me. I see some mild yellow edge-ringing around his right forearm, artifact of the sharpen filter. But for the life of me I can't see any yellow light, anywhere. /images/graemlins/frown.gif

Would have helped if there was something like a neutral-white reference ball to judge the color balance.

I do agree though that the skin along the shadow edges is showing sub-surface scattering of the light, being filtered through the blood inside.

Not trying to argue for/against blue speculars, I'm just not seeing it reflected in the real world. I do see however that it does serve to make a more varied surface, since we're mixing complimentary colors. Also I need to stop writing and start doing more. /images/graemlins/smile.gif

[melissa]

This is great information guys thanks.

[Etheros]

Eric. woah, respect. I'l learm 3dsmax with your books.
Glad to see you here.

[Eric Chadwick]

Thanks, man. Gotta say though that the knowledge pool is much wider around here than me, I've learned a ton more from the amazing people on this board.

And I've tried writing a book, well at least a chapter (http://www.ericchadwick.com/portfolio/html/chadwick_nrpsun.html), and it wasn't really worth the effort, for me anyway. You can learn a lot from writing though, so I encourage others to give it a go. It's just not a money-making proposition, is all.

[moose]

Specular is a monster, especially when coping with your normal. One thing to remember that ive been making sure ive paid attention to was that all details you put into your diffuse should, in some form or another, exist in all other textures.

You dont have to go ape shit and put noise all over your normal, but if there are major dark areas that are cracks or dings, it really helps to put this into your normal and specular maps. As for my process:

I will get a mesh, and all sorts of render files from Ror; a Normal Map, ambient occlusion map, lit render, lighting render, shadows render, color map, and height map. When texturing, i will generally maily use the occlusion, and lighting maps, set them to overlay / multiply at a light opacity to get the general form of the high poly baked into the diffuse (subtly).

From there i go to town on the diffuse, adding whatever it is that needs added. As i add major bits to the diffuse, i will go into the normal and get matching parts in it via the normal map filter in PS.

After chunking and detailing, ill build up the specular based on diffuse information, either completely taking areas of spec out, or really poping areas up so they shine. In order to get the most out of all 3 maps, you need to keep things consistent and flowing, so it doesn't look random.

For speculars, yes blues do work really well, and make some really pretty colors. However, you should think about what color your diffuse is, and what color you actually want the surface to be - since no one willsee your texture work in the dark, and light = specular. Ambient light will let you fill in the general colors, but when light hits it, there could actually be gold hidden under the grime. I try not to think about the technicalities of how light actually works (although ive read a bit to understand how it works and reflects light), and focus on "what looks the best?" If its blue, yay. If its gold, yahoo. Whatever is pretty /images/graemlins/smile.gif

[Eric Chadwick]

Nice. Glad to see your post here moose. What do you use these days for viewing/refreshing the combined result while you work? The game you're creating for, or another tool like Modo?

[moose]

no prob, ive been missing my PC roots lately /images/graemlins/smile.gif

i will go between a mix of Max, Maya, and just straight up in engine. Each has their drawbacks to make you grit your teeth, and make insane drawings, finding what works for you, and what shows off your work best is what matters.

Max is nice, because it is extremely fast for updating your texture, however... i havent found a good way to show specular, diffuse, and normal in real time. If i use max, it'll be for tweaking UVs.

Maya works, too and has the same perks of max (fast updating of updating textures), and some downsides of Max. You are able to have the specular show in the viewport in real time however it blooooooowwwsss the hell out of the images.

9 times out of 10, its best to just preview, view, and make decisions based on what the stuff looks like in engine, whichever that may be. UE3 allows for relatively quick importing, and provides instant actual feedback of what the final asset it. Likewise for any other engine - Normal maps and specular are handled different in each engine (i assume), so that its best just to view whatever you're doing in the medium you want to present it.

[Wrath]

[ QUOTE ]
Yeah, that's a good review Keg. Another here (http://itchstudios.com/psg/art_tut.htm), from a painter's perspective. You've probably seen it.

Hmmm, Per I'll have to disagree with you that the sunlight is yellow in this shot. The shiny wet parts look white to me. I see some mild yellow edge-ringing around his right forearm, artifact of the sharpen filter. But for the life of me I can't see any yellow light, anywhere. /images/graemlins/frown.gif

Would have helped if there was something like a neutral-white reference ball to judge the color balance.

I do agree though that the skin along the shadow edges is showing sub-surface scattering of the light, being filtered through the blood inside.

Not trying to argue for/against blue speculars, I'm just not seeing it reflected in the real world. I do see however that it does serve to make a more varied surface, since we're mixing complimentary colors. Also I need to stop writing and start doing more. /images/graemlins/smile.gif

[/ QUOTE ]

Big difference between real world lighting and RGB models. The blue tint to specular maps is probably done to counteract some of that unnatural color result because of the math involved.

Just as an example, if you were to take a red object in life and shine a yellow light on it, it would appear black. The red surface only reflects that portion of the spectrum, and the light doesn't contain that. On a computer however, 'red' is defined as RGB 255,0,0 and a 'yellow' light would be RGB 255,255,0...so you would see a red objects. Exactly the same hue as you would get with a pure white light. In order to get similiar results you'd have to use a pure blue or pure green (in RGB values) light as any red value would cause the object to appear red.

Why blue, probably because it's a complement to the red-green hues in most skin tones so you get appropriate looking specular highlights that won't oversaturate the base skin tone underneath.

And for the record, most black body type light sources tend to shift toward blue on the kelvin scale the hotter/brighter they are. Sunlight sits around 6500k compared to 'pure' white light around 5000k. Our eyes and brain do a fantastic job of white balancing under various color temperatures.

[Eric Chadwick]

That is a _really_ good point.

[okkun]

I found Max works pretty well for previewing normal and specular intensity/color. I think the only thing that doesn't work is having a map for specular falloff/glossiness so you'll need to use some imagination for that or render.

After Max 8 I think the texture download size for DX was improved so you can work with 2048's in the viewport while checking "DX display of standard material". (don't forget to up your normal bump to 100 from the default 30)

Once you bring it into UE3 you'd want to mess around with other things you can't do in Max but I rarely have to go into the engine until my normals and specular are ready for a more advanced material.

[J.I. Styles]

I agree with okkun on previewing in max, but I disagree with previewing in max if you're importing into ue3 -- ue3's specular and gloss ranges are completely different to what's possible in max. You can slide the intensity, but that's only a multiply value, there's still range differences to max from a 0 to 1 range. The saturation of specular is a big one too, and so is the specular hotspot "cone" (the bell curve that the intensity ramps to the peak of a 1.0 white). I'm a supporter of if you can preview in engine/editor while you texture, then definitely do so -- using the final shaders in a final lit environment will result in a faster and usually closer result to what you want since there's no translation task in-between.

[okkun]

Yeah I need to clarify that. I wouldn't suggest using max for absolute final tweaks/levels. I try to bake as many properties as possible so it helps having what is at least a good approximation of the final result while Im working.

If I can import my textures into an engine once that's brilliant. If I make sure it looks good in Max first the likelyhood of that happening is much greater.

[Sean McBride]

I've found that max is extreamly slow when you've got a couple 2048 sections loaded up (diffuse, specular, and normal) so i tend to preview all of my stuff in UE3. As long as you check that "Defer compression" you're good to go. Dosn't take much longer to import into your package than loading it up into max.

[fritz]

i don't understand color spec. whenever i try to load my color spec map in the color spec map slot in max maps...i get no spec whatsoever.

[Eric Chadwick]

fritz, works for me.

1. load diffuse, specular color maps.
2. crank up the Specular Level spinner.
3. turn on "DX Display of Standard Material"
4. turn on "Show Map in Viewport"
5. drill down into specular color bitmap, click its own "Show Map in Viewport" icon.

For some reason I have to "remind" Max that there's a color spec map there, otherwise I just get white spec.

hth

[CMB]

Wheres is DX display button everyone is talking about?

[Eric Chadwick]

Material has rollout called "DX something." Check the checkbox, then the Show Map In Viewport button (blue checkered box towards the top of the Material Editor) changes to a pink checkered box.

[Mr Ray]

Im having a few problems atm hopefully someone can point me in the right direction.
I used poops tut as my base of resource (btw any1 backed up mops normalmap tut on cgchat?) The normal map produces wires and I havent got any overlapping uvs, plus i cant get the viewpoint to see the normal mapping. Any suggestions?
http://img.photobucket.com/albums/v297/Mr.Ray/th_nm.jpg (http://img.photobucket.com/albums/v297/Mr.Ray/nm.jpg)

[Ruz]

only proble with the dx shaders in max is that they hog a hell of a lot of memory. workflow is normally:
oops made a mistake , try and undo then max crashes

[fritz]

Eric Chadwick...still no color spec. my spec works fine in the spec slot. then i went and added some color to one area of my spec map for a test. slapped that sucker in the color spec....basically did everything you typed out(thanks by the way)and still no color spec. s'weird. diffuse and normal are still there...just no spec at all. hmmmmmm

and Ruz...yes!!! i was wondering if it was just me. haha

[fritz]

OK...what a minute. i got it to work but i don't know if this is right or not. i loaded the color spec in the spec slot then i copied it to the color spec. and now it works kind of. am i supposed to have both: spec and color spec slots loaded w/a spec map? because when i just throw a spec map in the color spec slot i get nuttin.

[MoP]

yeah fritz, you need the map in the "Specular Color" and "Specular Level" slot in order for it to work right. Otherwise it's only affecting the colour of the specular, and not the power of it.

[fritz]

HAHAHA!!!!! YAY!!!!!!...another stoopid question by fritz answered. thanks MoP and eric getting closer....getting closer.

[fritz]

OK...here we go...gettin there for sure. liking what i'm seeing. a couple of things: first of all...why is there such a crazy desrepency(sp?) between spec in viewport and render...MY GOD MAN!!!!. and secondly, i come from a bit of an old school background...where you paint in shades of grey/white for spec. now, with the color...and i'm seeing some of it....but is it just one of those things that is supposed to be CRAZY subtle? i mean i've looked at rockstars color spec for his dominance guy...and there are almost no highlights on the face....just purple. i'm gettin so close...it's drivin' me mad. hahahahaha.

**nevermind on the render part. ha.

[Eric Chadwick]

Well, the color is also the power. The bitmap's colors multiply against the default white specular. The darker the color, the less specular you see. So if you put the same bitmap in both channels, your specular is going to be twice as dark.

AFAIK specular power can be calibrated quite differently between apps/game engines. In Max's case it's a linear 0-100 range, so 0,0,0 is no specular and 255,255,255 is 100% specular. Other apps may use a different range where 127,127,127 is 100% specular, and >127 takes it to a higher range (HDR-style).

[Joshua Stubbles]

MrRay - make sure you don't have an alpha channel of the wireframe in the normal map.

[dejawolf]

http://www.onona3d.com/pdf/texturing.pdf
a very good beginner tutorial on various shaders, surfaces, and such.

[snap.crackle.pop]

[ QUOTE ]
http://www.onona3d.com/pdf/texturing.pdf
a very good beginner tutorial on various shaders, surfaces, and such.

[/ QUOTE ]

Great dejawolf, i seen this sometime ago and lost the link.

Thanks

[PrayingMantis]

This thread is really great.
I was asking myself why did you use a bluish specular map for the skin, now I know it.
I was looking at this picture, and I don't understand the map.
The diffuse color seems to get no details and it seems to be the specular color who retains them.
But I think it misses the Normal Map.
Can you explain this map ?
http://shika.50webs.com/images/sumea_thumb.jpg (http://shika.50webs.com/images/acilia_main.jpg)

[Eric Chadwick]

PrayingMantis, image isn't showing up (artist is probably using hotlink protection for his images.) Probably this page: http://shika.50webs.com/images/girl.html

When normal and specular maps are being used, the dynamic lighting provides the details. He's using a normal map, just not showing it (subtext says so). If you bake high-frequency lighting info in the diffuse map, it tends to fight the dynamic lighting.

However he did add some soft shadowing in his diffuse, this helps when you don't have dynamic lighting that can add self-shadowing to the model.

[PrayingMantis]

Yes that's her, and for the hotlink, I have done a Thumbnail, sometimes it works sometimes not. I dunno why. If you only see a blue square click on it and it will work.
What disturbed me, was the details on the leather part, the sword and the gold part on the specular map.

[Eric Chadwick]

I think the best way for you to see what's going on is to borrow the textures, put them on some quickie geometry, and examine them with a game-style shader. I suspect that the sword would look better with better spec and diffuse choices, but it may look just fine as-is.

In general, I think it helps to look at it this way... if it looks good when moving around in-game, then it doesn't matter how ugly or odd the textures look on their own. It only matters that the sword shines nicely at runtime.

[PrayingMantis]

Hum ok that's a new prob, how can I preview it in Unreal Engine 3 ? Buying a game like gear of wars can provide me to custom and import some mesh like you can do it in previous unreal ?
Or did I have to be in the industry ?

[Eric Chadwick]

I hear http://www.roboblitz.com/ uses UE3 and comes with an editor. Or you could try one of the freebie apps here
http://boards.polycount.net/showthread.php?t=45485

[fritz]

so...instead of instancing a color spec in both specular slots...would it be more wise to drop a color spec map in the color spec map slot. and then a greyscale spec map in the default spec map slot?

[Eric Chadwick]

If you're using Max, I'd say use a colormap in the Specular Color slot for color and intensity both, and use a different grayscale map in the Glossiness slot for the width of the specular (white = tiny & tight, black = wide & super-soft).

Specular Level slot only does intensity. Specular Color slot works the same if you feed it a grayscale map, but it also allows purdy colours. http://boards.polycount.net/images/icons/smokin.gif

[fritz]

thanks eric. i will definitely give it a try.

cheers!

[seforin]

ok maybe im a bit off reading through all of this,

now creating a specual COLOR map you use in both Specular and specular color

you then take your texture sheet and make it a darkscale of it instead of grey scale?

and all things that would be shinner you make shiny manually (dodge tool or whatever)

But I see that people like rockstar and the link to that girl in the above, the faces are almost purple?

Can anyone explain whats the best way to go about making a specular color map here?

[Eric Chadwick]

Looks like you didn't read very much.

Two posts above yours, I answered your 1st question. As for your 2nd question, Wrath answered it (http://boards.polycount.net/showpost.php?p=632437&postcount=27) about 1/2 way through the thread. Your last question is a matter of personal preference, there's no one magical method. The best way is what lights well in your situation. IMHO experimentation is the best teacher.

[seforin]

ah so basically There is no easy way to do this? If you wanna do a color specular map instead of a gray scale map, you can just make the entire thing based off a shade of blue for skin (Which kinda explains that purple ive seen on a few) and then making things lighter or darker from there for glows and such?

[Eric Chadwick]

Glow is not specular, they're entirely separate effects.

I guess all the info in this thread is not sinking in, so I don't know how to re-phrase it so you'll hear what people are saying here. Hmmm. Try to think like shininess... a human face is usually more shiny on the nose than under the eyes, so the purple/blue tends work better when it's more intense there.

The best spec color maps are basically painted from scratch. It does help to blend in a cavity map or ambient-occlusion pass. Also helps to make the specular more intense along the edges of things, so edges get a little extra kick. But all the rest you need to paint by hand.

I've said it so many times, but it really does come down to this... improve your drawing and painting skills. These are the foundation. Once you have a solid visual understanding of the world around you, you'll get better at breaking things down into their consituent elements, like diffuse vs. specular vs. glow. Drawing is the process of seeing. Seeing is the foundation of reproduction.

[seforin]

no no no I understand , Ive just before used specular to fake a glow effect because it gave the extra shine to the area I needed. I usually paint a soft brush on my diffuse and then I tend to use a emissive map for brighter glow and then I would even go as far to paint on the specular map to give it a additional shine

and I agree about what you mean with painting and drawing to gain a better understanding to light around you, I do it day by day with drawings. I was just a bit lost as far as the best effect to create a specular map but I had a buddy best explain the easiest solution to go about creating it is to take your 2 channels from your RGB, play with the layers levels and then paint from there

[clee101]

For me, I figured that when I get to the texturing stage, I would let the normal map take care of the shadows and volume, and let my spec maps take care of the highlights and shine.. My diffuse map can look kinda flat, but it will have all the details and color. This works for me and have seen other artists do the same way.. The only thing im not too sure of is the specular color map. It's very tricky to get it to work and have yet to figure it out. Anyone have any good answers to it?

[Eric Chadwick]

Gloss Map handles the width of the highlight (white = tiny & tight, black = wide & super-soft), while the Specular Color map handles the brightness and tint of the highlight. Two different effects, not all games support both.

The darker the specular color map, the less specular you see. The reason to avoid just using grayscale values in the color map is to avoid some of the inaccuracy built into the CG lighting model (read (http://boards.polycount.net/showpost.php?p=632437&postcount=27)). For human skin, you can use blue/purple instead of grayscale. Also you can use color for metallic sheen (gun metal blue), fake iridescence (insect wings), or just general visual interest.

[Eric Chadwick]

Just saw this again, and thought of you. http://boards.polycount.net/images/icons/poly106.gif
http://www.iddevnet.com/quake4/ArtRefere...7ea3f511a7a1fab (http://www.iddevnet.com/quake4/ArtReference_CreatingModels#head-4152af2ebdcdf51e21eaf84fd7ea3f511a7a1fab)

[clee101]

Thanks alot Eric! ohh yeah, I saw those quake 4 tutorials too. I actually learned alot from those. I just skimmed thru those and I havent read into it in depth. Ill continue to study more into it and test things out. Thanks again.

[clee101]

I have another question on specular maps.. Where do you put in your specular map into in Max8? Specular color or specular levels and how much do you dial it up to 30-100? I found that when I dropped my spec map into spec color, I didnt notice the effect as much as when I dropped it into the specular level.

[Eric Chadwick]

I'd recommend using a realtime shader, like Ben Cloward's. Closer to real in-game performance than using Max's scanline renderer.

[clee101]

I see. I checked out Ben Clowards website as you mentioned and found lots of good stuff! Which one of the shaders would you recommend me to use? Simple normal map shader? Normal map specular shader? There were quite a few to choose from. Thanks again!

[Eric Chadwick]

Sure. Depends on what your model needs.

I guess this is for a portfolio piece instead of an actual in-game asset? If it was in-game, you'd likely use the game itself to see/adjust the shader. You always try to go with the least expensive shader you can, so your framerate doesn't suffer. But if it's just for renders/screencaps, then Ben's Normal Map Specular Shader - 3 Lights (http://www.bencloward.com/shaders_NormalMapSpecular3lights.shtml) is a good one.

I'd also suggest checking out the ShaderFX (http://www.lumonix.net/) tool he's working on, should give you more insight into how shaders work, why you'd choose one over the other, and lets you design new ones. Pretty cool project.

[Rob Galanakis]

Here's an article I am working on that may give some info as well.

http://www.twcenter.net/wiki/Shaders

BTW, I can't recommend ShaderFX enough, its a great tool!

[bounchfx]

this is a great thread, but one thing that confused me .. I was looking at the image of the girl: http://shika.50webs.com/images/girl.html
and I see the spec color map, especially the skin.. and I got to thinking - isn't the specular color the color that shows when theres a light on it? if that is the case why isn't her skin the blueish/purple color? her stomach and face are obviously being lit.

Can anyone explain this to me? Thanks a lot!

[Vailias]

sort of but not fully. The specular color map won't replace the diffuse color, but be added to it (or some other positive mathematics)so if you add a blue color to a predominately red or orange area you end up with a whiteish highlight. (think in RGB color theory)

If you simply added white it would wind up washing out in the falloff and looking more plastic like.
Now if you had the spec color as an orange or yellow the skin winds up looking like its glowing or otherwise not fully natural, but not necessarily bad, but certainly a stylized effect.

[Rob Galanakis]

The skin color he uses is .85 .62 .48
The skin specular color is .19 .26 .28

Specular lighting is added to the diffuse lighting (let's just assume the diffuse factor is 1), meaning, if the specular were 1 (at the center of the highlight) we'd have 1, .88, and .76. The colour is still slightly reddish, but almost white.

If we have a specular factor of .5, we'd end up with about .95, .75, .62. So you can see, the bluish specular colour counter-acts the reddish skin colour, so we get a nice whitish highlight (skin specular is white because of the oils).

[bounchfx]

Ohh, so the spec adds to it? interesting.. but still mildy confusing, I'll have to play with it a bit, because I've seen some shots showing specularity at the full color of the spec color map and not just blended.. I think..

I gotta play around with this stuff.

but neat, thanks

[Ged]

wow good thread, just been reading through some of this and I was wondering if some of you guys in the industry could tell me some specifics.

what channels should I use in max if I want to make a typical next gen game model. Say I have made a colour, specular colour and normal map.

Can I turn on : colour, specular colour, specular level, glossiness and normal map in max?

the specular colour, specular level and glossiness could all use the same map right?
do games really support all these?

I have been using ben clowards shaders a bit lately, is this more likely the way forward? should I just ignore the typical max settings?

[NeoShroomish]

Glossiness goes in the glossiness slot. Source supports greyscale specular, normals and a gloss map, and it's current gen, so yes.

[Eric Chadwick]

[ QUOTE ]
the specular colour, specular level and glossiness could all use the same map right?
do games really support all these?

[/ QUOTE ]
Yes they do, although Specular Level is just a grayscale version of Specular Color. Use one or the other, depending on what you want, not both at the same time (otherwise you'll be double-reducing the spec amount).

Glossiness (aka Specular Width, Specular Power) is a different beast altogether, and typically only grayscale (you could wire different gloss widths per RGB color channel, but you don't get much bang for the buck).

To take advantage of these in Max you'll want to ditch the default Max materials in favor of custom FX or HLSL shaders. Ben Cloward and J.I.Styles have some nice presets. ShaderFX is another nice way to go.

[Ged]

Thanks Eric, I will try this when Ive got my fzero ship done, whenever that is :P. Im thinking of buying roboblitz just so that I can get some stuff into the UE3 engine and play with it there.

[pillowsama]

Wow, that was a lot of help... but it seems like all these are only available in max, is it possible in maya at all? with color spec maps and all that?

[Eric Chadwick]

pillowsama: I did a Search using +maya +specular +shader and found this...
http://boards.polycount.net/showthread.php?t=48294

Search is your friend, my friend.

[Ruz]

so what is the point of a glossy map. The effect of a gloss map as opposed to a numerical value seem so similar as to not worth using one.

[Eric Chadwick]

Per-pixel, baby!

If you're using a different shader for each surface type (skin vs. cloth vs. metal), then might be best not to use a gloss map. Each shader would use a different numerical specular power (power/gloss/width = same thing). More batches, but faster fill rate.

If you're using the same bitmaps/shader for multiple surface types, but you want different specular widths, then a glossmap is the way to go. Less batches, slower fill rate.

Depending on hardware of course, just talking general performance here.

[Ruz]

he he, that was so obvious Eric , yet i never thought about it purely in those terms. i was looking or some amazing extra effect that using gloss maps might give.
Obviously even a very simple gloss map would give you the desired variation without extra passes. cheers for that

[pillowsama]

holi, thnx i'll keep that in mind hehe, I've been working on my portfolio, learnt a lot from character modeling 2, the pipeline from gears works just perfect ... but there are just little things like this that I wish to be better, but thnx i'll keep that in mind and search more next time!

[Ruz]

I was thinking for about specuar maps and it occurred to me that use a texture could in some ways interefere with the specular look. For example a spec map would be used to make sure for example the beard line is not shiny (for a simple example)
the cheeks nose etc would be normally be slightly shiny. Now using a texture , you quite often have a dark area in the folds of the eyes where the nostrils are/ sides of the nose, because usuallly you have taken the spec from a desaturated diffuse map.
the problem here is that quite often these dark bits are the areas that in reality would be most shiny ie mucus membranes.

My point is that surely the normal and the lighting would make the spec shine in the right places and combined with spec power and a greyscale specular strength outlining broader areas would be more accurate.

EDIT actually what i really meant was that 3d sepcular stuff sucks

[Eric Chadwick]

Most real-time lighting doesn't cast a enough of a decent self-shadow, so for me the spec color map helps solve that problem, by making sure I avoid that unwanted unshadowed lighting in the cracks & nostrils.

Mass Effect is one example of how bad self-shadowing can be, remember the vids where the blocky shadows shimmer all over their faces? I imagine they'll throw some time at it before it ships, but there are always a lot of things to do at the end of a project.

I disagree though, 3D specular can really rock, if you have the tools/support for it.

[Ruz]

I think get your meaning eric. its like you can't rely enough on the proper lighting/shadows, so you have to fake it a little with the spec map. gives it a kind of consistency

[Eric Chadwick]

Yeah. Same thing with using a blue spec color for skin (which I learned in this very thread)... another trick to compensate for some of the idiosyncrasies in game lighting.

[Malus]

Hey everyone, quick question for the collective 3D hive mind.

I remember seeing an interesting technique to create normal maps which I'd like to use on a current project. Problem is I can't remember where I saw it .. :P

From what I recall you created a light rig consisting of a red, blue and green light within maya, this rig lights the 3D mesh you'd like to use as a base for the map.

Once lit you take a screen grab from the front viewport which can be used as a normal map.

Seemed like a great fast way to to use existing objects to make normal maps.

One cool aspect was the mesh could use the existing normal maps applied to the mesh to add detail to the captured texture.

If anyone recalls how its done or has a link that would be fantastic.

Or alternatively if I'm just smoking too much crack and it never existed then thats good too. /images/graemlins/smile.gif

Cheers.

[aniceto]

this?
http://i32.photobucket.com/albums/d3/shika01/normalmap_LightDiagram.jpg

[Malus]

I'll give it a go Aniceto, thanks mate.

I did find a quick solution using Xnormal's bake normal from photo function which worked really well.

Just set up a quick scene to light the mesh in from the left, right, top and bottom.

Thanks though. /images/graemlins/smile.gif

[monkeyboy_garth]

[ QUOTE ]


From what I recall you created a light rig consisting of a red, blue and green light within maya, this rig lights the 3D mesh you'd like to use as a base for the map.

Cheers.

[/ QUOTE ]

Yeah, I remember seeing exactly the same thing. I can't remember where I saw it though.

http://www.bencloward.com/shaders_NormalMapMaker.shtml this sounds similar but not exactly what you're talking about. It's for max too I think. Bugger, I can't remember where I saw that rig/tutorial - it's killing me!

btw give us Hellboy!

[Eric Chadwick]

http://www.pinwire.com/articles/26/1/Generating-High-Fidelity-Normal-Maps-with-3-D-Software.html
and
http://farm2.static.flickr.com/1203/1330615923_6ce00c07fc.jpg (http://electricbiscuitonline.blogspot.com/2007/09/knitted-hellboy.html)

[monkeyboy_garth]

Snap! Thanks - that's awesome.

[verybad]

Oh MY god. That's better than real. THat's can't be done, I must be dreaming.

[Keg]

I'm pretty sure that's actually handmade and not a cg render.

http://www.etsy.com/shop.php?user_id=1271 <- rest of that user's work.

[dejawolf]

eureka! its all so clear to me now!

specular surfaces are always darker than non-specular surfaces! non-specular surfaces scatters the light more, showing less of the colour to the human eye!
and of course you get the bonus that specular surfaces has better contrast.

[rooster]

i dont think I follow your epiphany deja can you explain more?

[dejawolf]

well, its blindingly obvious. wet matte paint is dark, but when it dries, it turns lighter!
however, if you spray water on it, it becomes dark again.
the more matte something is, the darker it becomes when wet.
gloss paint on the other hand doesnt turn darker when wet(well maybe a little dark because of shadow)

glossy surfaces' highlights has very bright shine, because it reflects more of the light from the lightsources to your eye, instead of spreading it into a broader highlight which can be seen at steeper angles.

[Rob Galanakis]

Indeed, such a phenomenon has to do with the conservation of energy. The GPU Gems3 chapter on Skin Rendering has a bit about how they apply it (pp 332-336), not sure if it is in the web version as well.

[dejawolf]

today i made a discovery. i discovered my white porcelain bowl is translucent.

[Rob Galanakis]

[ QUOTE ]
today i made a discovery. i discovered my white porcelain bowl is translucent.

[/ QUOTE ]
http://graphics.ucsd.edu/~henrik/images/subsurf.html

[stalsby]

If I have say about 20 separate parts for my lowpoly model, what would be the best way to project my normal map? I have to get it all in on one 2048 map for dominance war.

I'm not sure if I should try and import all my highpoly parts at once and make one single cast or do them separate and piece them together somehow. If anyone has some experience with this please shed some light, Thanks!

[pior]

Make a single cast, but spread both the low and the highpoly pieces appart at distances you can remember easily (100 units, 200 units aso). Then put them back together once baked.

[stalsby]

Cool, Thanks for the info!

[pior]

http://www.saphrym.com/blog/wp-content/uploads/2007/05/50e7b552c45ad275.jpg