Marmoset / General Specular Question

ericdigital

I'm not exactly sure if there is a term for what I'm having a problem with but going to explain it the best I can.

I'm currently using marmoset and trying to get the specular effect on a round object where the highlights shoot out from the center like the images below.







In marm the only options there are kinda is phong or anistropic








So anistropic seemed like it was a step in the right direction and i figured since the geo doesn't come to a point that was the reason, I tried a quick test and it didn't yield any results.





Is this something I can do in marm? Should I try to just fake it with a spec map/fancy light placement? I feel kind of lost! Hoping it's just something I'm naive to.


thanks for any info/ideas guys

Ace-Angel

When you have something set to Anistropic, you should also have the option for a Aniso/Flow Map, which will dictate which direction the Specular highlight will bend in.

Problem is, generating them isn't exactly easy last I checked, and something like that is simple, but the generation process doesn't exist.

Here's an example of what it would look like for a round object: http://udn.epicgames.com/Three/AnisotropicLighting.html

Lastly, if you do a quick search in Technical Talk about anistropy, there should be several threads discussing on how to tackle in Photoshop AND a plugin for Max.

ericdigital

Cool thanks Ace!, I seen the option for the flow map but wasn't able to find much info on it. You've set me in a good direction!

Kurt Russell Fan Club

Anisotropic is exactly what you're looking for. I haven't used Marmoset recently but I believe it gives you a slot for loading in a tangent map (I think they call it direction?). That's a texture map like normals but instead shows the direction your tangents go.

You should be able to get a good direction map using the angle gradient tool in photoshop.

Edit: ninja'd!

walreu

thanks everyone, i need this effect for one of my works too..

ericdigital

Kurt Russell Fan Club wrote: »

Anisotropic is exactly what you're looking for. I haven't used Marmoset recently but I believe it gives you a slot for loading in a tangent map (I think they call it direction?). That's a texture map like normals but instead shows the direction your tangents go.

You should be able to get a good direction map using the angle gradient tool in photoshop.

Edit: ninja'd!

Interesting Mike, So I was playing around with just a Black and white image using the angle gradient tool before I went to bed last night and was def getting pretty close results. Is this basically what you were suggesting?




It seems to work pretty well except in addition to having some pretty decent results there is a highlight that still glides across the entire surface? Is it because this is only a B+W map, or is that just a unavoidable part of aniso surfaces? Perhaps I would have to get a little fancier and build more of a tangent map?

Thanks again for the responses guys

r_fletch_r

the map should look more like this. no idea how to generate it myself. read the doc ace posted.

ericdigital

Right. I've been looking around at a few diff sources on how to make them but I'm pretty lost. My super ghetto B+W map works surprisingly well with marm but not perfect which I'm not sure if marm even supports the type of map you and ace posted. There doesn't seem to be any documentation. Oh well, gonna keep poking around!

Ace-Angel

Not the proudest moment for me, but I essentially took that image, cropped the 'Aniso' map, blurred it abit in PS to get rid of Artifacts and stuck it on my model. You could do that...maybe?

There is also one floating around google, but couldn't find it again

As I said, the math does exist on how Aniso will be calculated for your mesh via the mesh AND the normal maps, but it's the baking part that doesn't exist for said stuff, you have to rely on things like VRay, Mental Ray, etc during render time, especially for inorganic stuff like the shield.

We just recently found 'somewhat' ways to paint Aniso maps for hair and water, which are very forgiving in nature.

Yeah, I know it sucks, but if worse comes to worse, you could fake the Aniso effect maybe? You know, cover it in dirt, have 4 strong streaking highlights only, etc...

ericdigital

hilarious ace, I tried the same thing Either the quality was just to darn poor or marm uses different values since it ended up with a lot of artifacts.

Pretty interesting stuff. I think that's pretty much what I'm going to do. Using the really ghetto B+W map and just faking some stuff in my spec/diff I'll be able to get a satisfactory result for still images at least.

Appreciate the help

ericdigital

I just found this online, which is what I bet you were mentioning Ace




Not home right to test right now, but I wonder if it would work in marm


Found it on this wiki

http://www.unifycommunity.com/wiki/index.php?title=Anisotropic_Highlight_Shader

Ace-Angel

Yep, that's the one...I think...you can try removing the Blue channel and see if it still works in Marmo or use as is.

ericdigital

Just a quick update, It ended up working decently but there doesn't seem to be any solution to control the offset of the highlights, so if its not at an extreme angle the center point of the highlight floats around.

Thinking of maybe just using unreal instead to present since it seems a bit easier to pull off. I was reading threw Ben's thread and them getting direction working with Xoliul but didn't see anything about metal surfaces like this. Had no idea this was such a elusive thing!

Ace-Angel

Hmm, mind if you try something? Try putting up a directly Green or Red color in the Direction slot for Marmoset, or maybe Yellow even.

Also, use the second shield you created, the one with the pointy center.

I'm not sure what math Marmo uses, which is half of the issues, maybe they have more information in their thread?

Drew++

For Marmoset, something like this might be what you're looking for. **edit** this works on a flat plane, Idk about a hemisphere/round shape?

Here is the anisotropic direction.


Hope this helps! :P

pior

Yup - that sure looks better than the "blackened" preview in that UEd screenshot. Fingers crossed!

ericdigital

Very interesting guys, I will try some tests when I get home from work and update with the results!

Thank you for keeping the suggestions coming!

Drew++

Here's an example with a normal map, and some color. I tried to make it look a bit more like brushed metal. If it's too strong you can just blend it with the normal one I posted earlier.

here's the map

Dylan Brady

Nice! maybe the brushed look would be better if handled by the spec?

ericdigital

yayy you guys are awesome!

@Drew - Those maps work great! I guess the only thing I really wonder now is when I was doing tests on the tangent space looking map I found earlier, I had tried inverting it, which made it almost look exactly like the maps you posted but it didn't yield any results. Are the maps you generated basically just from baking out a cone? Thanks a ton for the help man, really appreciated!


Thanks again everyone for your input!