KeyShot Forum

Technical discussions => Materials => Topic started by: cjwidd on September 25, 2017, 11:02:11 am

Title: [RESOLVED] Why can't a color adjust node be passed into a bump channel?
Post by: cjwidd on September 25, 2017, 11:02:11 am
Why can't a color adjust node be passed into a bump channel?
Title: Re: Why can't a color adjust node be passed into a bump channel?
Post by: mattjgerard on September 25, 2017, 11:23:02 am
Interested in this as well. Would like to use the color adjust utility node on bump maps and noise textures, but can't. Maybe it might be a black and white requrement of the bump input vs an RGB output of the color node.
Title: Re: Why can't a color adjust node be passed into a bump channel?
Post by: MWo on September 25, 2017, 11:36:57 am
There are several threads discussing this topic. Perhaps in a future release but not in the current.
If you use a raster texture (file) you can use a graphic tool like PS and manipulate/reload the bump or normal texture.
Title: Re: Why can't a color adjust node be passed into a bump channel?
Post by: cjwidd on September 25, 2017, 12:28:04 pm
My apologies, but thank you for your response, it is much appreciated.
Title: Re: Why can't a color adjust node be passed into a bump channel?
Post by: cjwidd on September 25, 2017, 03:38:38 pm
There are several threads discussing this topic. Perhaps in a future release but not in the current.
If you use a raster texture (file) you can use a graphic tool like PS and manipulate/reload the bump or normal texture.
Does this imply that a curvature mask, cannot itself be used to modify the height of a texture layer? For example, is it impossible to use a curvature mask as a bump map?
Title: Re: [RESOLVED] Why can't a color adjust node be passed into a bump channel?
Post by: MWo on September 25, 2017, 10:30:07 pm
I think it should work to crop, but didn't tried it on the last release.
Title: Re: [RESOLVED] Why can't a color adjust node be passed into a bump channel?
Post by: DriesV on September 26, 2017, 01:21:43 am
Without getting too technical, the underlying reason is that under the hood all bump maps are actually applied as normal maps.
This means that any color adjustments to a bump map (which is converted to/interpreted as a normal map) are basically nonsensical.

I hope that helps to understand why the Material Graph behaves this way.

Dries
Title: Re: [RESOLVED] Why can't a color adjust node be passed into a bump channel?
Post by: mattjgerard on September 26, 2017, 06:10:25 am
Without getting too technical, the underlying reason is that under the hood all bump maps are actually applied as normal maps.
This means that any color adjustments to a bump map (which is converted to/interpreted as a normal map) are basically nonsensical.

I hope that helps to understand why the Material Graph behaves this way.

Dries

That does explain alot, and also provides a reason why! It makes sense, since all bump maps are essentially limited scope normal maps. In fact some other render engines have gone away from using bumps at all. THanks for the explanation, it really is appreciated!
Title: Re: [RESOLVED] Why can't a color adjust node be passed into a bump channel?
Post by: cjwidd on September 26, 2017, 03:15:51 pm
the underlying reason is that under the hood all bump maps are actually applied as normal maps.

Oh wow, that makes a lot of sense, thank you for this clarification.