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When i was sitting in the train (doing nothing), i looked at my iPod and saw that the scratches on the back were not all visible at the same time. If i turned it, while holding it in direct sunlight,
the scratches would sort of change direction and disapate. Other scratches would become visible at the same time. This had to be the effect of pushing the chrome back over surfaces in different
directions. Or sometimes rotating because some the scratches were twisted or round.

I wanted to recreate this in Maxwell. Since there is no such material in the MXM gallery other then scratched chrome with only one scratch map.

In order to achieve this, you have to have at least two maps on two different BSDF's. The more BSDF's, the more scratched the surface will be. (that was my logic)
Because that my iPod was scratched A LOT, and to demonstrate it clearly, i used 12 BSDF's. In those BSDF's i used 2 different textures, rotating them in photoshop gave the desired effect.
I used Hiltom's scratch map and an other map from the MXM gallery. (don't know the users name)

This is what i came up with so far; the left one is without a anisotropy map, the right one is with.




To be honest i don't know if my anisotrophy map is correct mapped or if it's even correctly used;




Are there any suggestions on anything to improve the material??


Gr Joep

You got some pretty good results but it's not quite "there" yet, i tried this myself in the past but i always failed in reproducing the circular scratched effect around the highlights on the surface. I'm not even sure if it can be done correctly. Perhaps someone more experienced can give some better feedback on this one. I would be interested in understanding how and if it can be done with Maxwell.

/ Max

That's exactly what's happening on my iPod and that's not what i'm getting here, so you're right, i'm not finished.

I took another look at the scratched back and i think i know the awnser. I you look closely you see that the circular scratches are not circular but just straight, little scratches. Essentially a circle
is made of very small straight lines, the more straight lines the rounder your circle looks. Just as in your 3d package. So what i have to do is create many BSDF's (71 or so) with Hiltom's scratch map turned +5 degrees for every BSDF.
If only MXED had a rotation setting...

That should work

Or you could combine them all in PS?

It looks good so far. I don't like the bump, it looks too strong. Maybe lessen the bump, and see how it looks. Here is the result I have achieved so far. A different kind of scratch, though. I might try with heavier scratch maps to see if I can come close to the result you've achieved.

Or you could combine them all in PS?

I tried that and it's not the same. If you put al the maps on top of each other using Multiply the black scratch lines create a different pattern and the scratches al reflect the same light, as they are
the same bump map.

But I'm doing a test now with 36 BSDF's, lets see where that gets us

Looking forward to see your results TokTok.

Here's two quick tests i just threw together.



/ Max

Great to see you guys are bearing with me!

I'll post this last one before going to bed; i think i'm gettin there but the scratches are way to heavy. It completely blurs the chrome while my roughness is set to 5.
But the 36 BSDF material worked as i hoped Now I only need to perfect the scratch map, these have too many scratches.




So the left one has the scratch maps perfectly aligned and +5 degrees each. You can see the sort of tiling happening. That's not right, so i created the right one.
Lowered the bump to 2, used a different scratch map and gave all the maps a different offset. The material still has an anisotropy of 50. Is that correct on chorme?
What do you guys think?

Btw i think if you want to do it perfectly you would need a unique scratch map for every 5 degrees.

The one on the right is looking cool!

Bubbaloo wrote:The one on the right is looking cool!

Agree!

With less density on the scratches and possibly less layers (unless you've been kicking your ipod down the road)!

What do the scratch maps look like? I did one with a wacom tablet and just drew scratches in sort of circular pattern, because of the pressure sensitivity you don't get just a white or dark stroke, so the bump strength varies a bit across the surface.

The anisotropy is not a 'fixed' amount for a certain metal, it all has to do with the surface scratches so by applying a bump map with scratches that run in one dominant direction, you get more anisotropic reflections (the surface has more specular reflections in one direction and blurrier reflections in the perpendicular direction) instead of isotropic reflections, without using the anisotropic setting at all. The anisotropy parameter is ment to mimic these directional grooves on the surface, but if you use a fine highrez bump map you can basically get the same effect. Still in these cases the anisotropy parameter can help boost the effect.

Bubbaloo wrote:The one on the right is looking cool!

You mean you have 24 inches display or more? Now, that's the one at the bottom for me...

tom wrote:

Bubbaloo wrote:The one on the right is looking cool!

You mean you have 24 inches display or more? Now, that's the one at the bottom for me...

How do you work??

Tok_Tok- that one on the right (bottom for Tom ) looks really really close and something that I have been trying to achieve since I started using Maxwell!!!! Do you feel like sharing your maps? .... there is no emoticon for begging so please take this as such
Very cool

What do the scratch maps look like? I did one with a wacom tablet and just drew scratches in sort of circular pattern, because of the pressure sensitivity you don't get just a white or dark stroke, so the bump strength varies a bit across the surface.

The anisotropy is not a 'fixed' amount for a certain metal, it all has to do with the surface scratches so by applying a bump map with scratches that run in one dominant direction, you get more anisotropic reflections (the surface has more specular reflections in one direction and blurrier reflections in the perpendicular direction) instead of isotropic reflections, without using the anisotropic setting at all. The anisotropy parameter is ment to mimic these directional grooves on the surface, but if you use a fine highrez bump map you can basically get the same effect. Still in these cases the anisotropy parameter can help boost the effect.

This is what the map looks like;




This one is from Hyltom. But i need one that's less dense and, as you explained, with pressure sensitive strokes.

As i said before, i'm missing a rotation setting in the UV settins in the MXED. Now i rotated the map 35 times in photoshop, but because the lines in
the texture are 1 pixel in height they get very antialiased and lose quality. If you could turn them in MXED you would only need 1 map and the quality would stay the same.

Anyway, i'm doing a test now with half the BSDF's and no anisotropy.

caryjames wrote:Tok_Tok- that one on the right (bottom for Tom ) looks really really close and something that I have been trying to achieve since I started using Maxwell!!!! Do you feel like sharing your maps? .... there is no emoticon for begging so please take this as such
Very cool

Hold on! It's getting better

When i got the final MXM i'm going to upload them to the MXM gallery anyway, so no need to beg