KeyShot Forum

Technical discussions => Textures => Topic started by: zooropa on August 23, 2017, 03:04:50 AM

Title: Applying a bump through curvature mask ?
Post by: zooropa on August 23, 2017, 03:04:50 AM
Hi. I am texturizing a violin in KS. I started with a wood material from Esben Oxholm (please check Esben Oxholm web for the vintage stool scene). After that I have been tweaking the wood material.

I would like to add a detail where the 'lips' of the violin are encountering with the flat surfaces in order to give a worn effect. I used curvature parameter and use a noise as an input for the 'negative' parameter within curvature. My idea was to add that effect to the 'bump add' palette since I already have a few from Esben wood working at the moment connected to bump 1. The problem is that I can not assign curvature to the bump 2 in the 'bump add' parameter I am unable to do that. Do you know how can I add this noise procedural in my negative curvature as a bump to the already bumps connected to my bump 1 in the add bump option ?

Super unclear?

Title: Re: Applying a bump through curvature mask ?
Post by: cjwidd on September 22, 2017, 03:31:42 AM
It would be very helpful to see some screenshots of your progress in addition to your material graph
Title: Re: Applying a bump through curvature mask ?
Post by: zooropa on September 22, 2017, 06:02:23 AM
Thanks, this was solved. Regards
Title: Re: Applying a bump through curvature mask ?
Post by: cjwidd on September 22, 2017, 06:16:27 AM
Would you mind posting your solution? Others might benefit when consulting the forum for advice.
Title: Re: Applying a bump through curvature mask ?
Post by: DMerz III on September 22, 2017, 12:13:00 PM
 :) yes, I'd also like to see your solution. Thanks!
Title: Re: Applying a bump through curvature mask ?
Post by: zooropa on September 26, 2017, 02:24:26 AM
I did not solve, but the client did not want that. hahaha I guess 'solve' was not the right term.

Title: Re: Applying a bump through curvature mask ?
Post by: cjwidd on September 26, 2017, 02:59:50 AM
Haha, I guess that worked out. Thanks for updating though
Title: Re: Applying a bump through curvature mask ?
Post by: DriesV on September 26, 2017, 04:54:18 AM
You can't use a Curvature (or Occlusion) texture as a bump map, much for the same reason as mentioned here (https://www.keyshot.com/forum/index.php?topic=19881.msg83691#msg83691).
That being said, you can use a Curvature texture to control the Weight of a Bump texture in the Bump Add utility node.
Attached is a screenshot of the most basic Material Graph to achieve this and a comparison between different bump setups to highlight the effect.

I am not sure if this is what you are looking for, but the technique works well for recreating worn materials.

Dries
Title: Re: Applying a bump through curvature mask ?
Post by: mattjgerard on September 26, 2017, 06:05:13 AM
saved to the goodie list :)
Title: Re: Applying a bump through curvature mask ?
Post by: DMerz III on September 26, 2017, 07:23:15 AM
That's good stuff right there, thank  you for the breakdown, Dries!

I had done something similar in the past but used the curvature on the 'bump height' input. Your example seems to work in a more predictable manner.
Title: Re: Applying a bump through curvature mask ?
Post by: zooropa on September 26, 2017, 11:04:13 AM
This is a great tip. I think this is what I wanted. In a way I wanted to drive the bump on the curvature. For example, when you sand wood at corners, the radius will seem to the hand a little bit grainier. I wanted to drive, let's say, a noise into the radius of my wood.
I think I need to try with this technic, but should work.

Thanks a lot.

Title: Re: Applying a bump through curvature mask ?
Post by: NM-92 on September 26, 2017, 11:57:26 AM
This should go on the wishlists section, but these kind of tips (Dries) shouldn't be lost here and there on the forum. Some kind of "tips n' tricks" manual would be more useful than the KS documentation itself.
Title: Re: Applying a bump through curvature mask ?
Post by: cjwidd on September 26, 2017, 03:59:55 PM
Quote from: DriesV on September 26, 2017, 04:54:18 AM
That being said, you can use a Curvature texture to control the Weight of a Bump texture in the Bump Add utility node.

Firstly, thank you for all your tutorials on Youtube, they are immensely helpful. I think I understand what's happening in your example: the noise bump is only allowed to appear in the (white) curvature masked area.

Just so that I am clear, in the attached image, you can see the output of a curvature node (after contrast enhance, etc.). My plan was to pass this mask into a bump channel, and then setup a label structure, such that metal would appear under a plastic. Using the curvature mask as a bump, the plastic would appear to 'sit' on top of the metal, as it would if it were actually damaged and coming off. Due to reasons you described elsewhere, I'm not sure this is possible at this time.
Title: Re: Applying a bump through curvature mask ?
Post by: DMerz III on September 27, 2017, 12:12:41 PM
Hmm, I think in that case, you might want to plug it into the opacity channel of the label? What is white will be label and what is black will be 'metal' or not label.. if that makes sense? I think that's what you want?
Title: Re: Applying a bump through curvature mask ?
Post by: Esben Oxholm on September 29, 2017, 12:51:20 AM
Quote from: DriesV on September 26, 2017, 04:54:18 AM
That being said, you can use a Curvature texture to control the Weight of a Bump texture in the Bump Add utility node.
Attached is a screenshot of the most basic Material Graph to achieve this and a comparison between different bump setups to highlight the effect.

Hi Dries.
Not to question your knowledge, but wouldn't this setup achieve the same effect?
Or would there be some kind of difference?
Title: Re: Applying a bump through curvature mask ?
Post by: DriesV on September 29, 2017, 02:02:37 AM
Hi Esben,

It is quite similar, but the limitation in your setup is that the (exact) bump height is hard to control. The Height will also be limited to a maximum of 1, since the maximum value (brightness) of a texture is 1.
You would need to add a 'Color To Number' node in between the Curvature texture and the Noise texture, in order to control/extend the Bump Height.

Dries
Title: Re: Applying a bump through curvature mask ?
Post by: Esben Oxholm on September 29, 2017, 03:24:10 AM
Quote from: DriesV on September 29, 2017, 02:02:37 AM
It is quite similar, but the limitation in your setup is that the (exact) bump height is hard to control. The Height will also be limited to a maximum of 1, since the maximum value (brightness) of a texture is 1.
You would need to add a 'Color To Number' node in between the Curvature texture and the Noise texture, in order to control/extend the Bump Height.

Okay, cool. Thanks for the clarification.
Title: Re: Applying a bump through curvature mask ?
Post by: DMerz III on September 29, 2017, 07:12:26 AM
 :) That makes sense, thank you!