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specular maps and normal maps

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  • 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. smokin.gif
  • fritz
    thanks eric. i will definitely give it a try.

    cheers!
  • seforin
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    seforin polycounter lvl 12
    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 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
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    seforin polycounter lvl 12
    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
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    seforin polycounter lvl 12
    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). 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
  • 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 is a good one.

    I'd also suggest checking out the ShaderFX 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
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    Vailias polycounter lvl 14
    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
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    Ged interpolator
    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
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    Ged interpolator
    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
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    Ruz interpolator
    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
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    Ruz interpolator
    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
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    Ruz interpolator
    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
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    Ruz interpolator
    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
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    Malus polycounter lvl 13
    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. smile.gif

    Cheers.
  • aniceto
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    aniceto polycounter lvl 14
  • Malus
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    Malus polycounter lvl 13
    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. smile.gif
  • monkeyboy_garth
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    monkeyboy_garth polycounter lvl 9
    [ 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
  • monkeyboy_garth
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    monkeyboy_garth polycounter lvl 9
    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
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    Keg polycounter lvl 12
    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
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    dejawolf polycounter lvl 11
    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
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    rooster mod
    i dont think I follow your epiphany deja can you explain more?
  • dejawolf
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    dejawolf polycounter lvl 11
    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
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    dejawolf polycounter lvl 11
    today i made a discovery. i discovered my white porcelain bowl is translucent.
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