PBR shader setup in TG (was re: Speedtree 8)

Started by Matt, February 27, 2017, 09:38:58 PM

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cyphyr

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KyL

Nice result! Yours is definitely sharper.

Also I forgot to mention that bur for example in in your roughness image map shader, you should change the projection type to "object UV". If you leave it by default it is not going to match the color texture as it will be projected from the top, which is going to look really weird!

Matt

#17
Hi Doug,

The way you are using both a displacement image and displacement function, The Default Shader will multiply them both together. I don't think that's what you want.

The same for your roughness image and roughness function.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

zaxxon

Hi Matt, I guess my approach was to keep adjusting the settings and 'eyeballing' the image. Not very scientific for sure.  So if my misuse of the shader logic produces an acceptable image, would proper settings improve the image?  :) I did about 40 render variations of various settings and the combination attached seemed the best looking of the lot; given the ones I used, what would be a more optimal range?

Thanks Kyl I'll change that and re-render.

Matt

Well, given that the image map shaders had the wrong projection mode, they are probably just confusing the results and I would just take them out. Simply plug your image filenames into the image fields of the Default Shader and tweak the multipliers from there.

Having said that, if you use the Image Map Shader plugged into the function input you have more options for colour space (gamma versus linear), and that might get you closer with the roughness and bump. But I doubt it matters on this particular asset. If you do go down that route, use them instead of the built-in image field, but not both at the same time.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

zaxxon


zaxxon

#21
See below

zaxxon

I've probably killed enough brain cells in this exercise. ;) However, I think that I can better reproduce the quality of the assets in TG which was my goal. I did as Matt suggested and used just the image maps in the default shader slots with good results. I also used the functions without the image maps in the default slots (except for the albedo map), also with good results. Tempting the fates, I used both the default image slots as well as the function slots for specular and displacement. Finally I added one more example which had a higher displacement multiplier. To my eye the images are pretty close, there is a detail blow-up of the area in the asset that was my comparison point and honestly I really don't see much difference. The simplest solution to just use the default shader slots is probably the best (easy beats complicated   :)). here's the breakdown:

Example A:  Using only the image slots in the default shader. Albedo in color image slot. Specular map in reflectivity slot, no roughness image, roughness set to .8. 'Bump' map in Displacemt image slot, did not use             provided displacement image.

Example B:  Function driven (mostly). Albedo in default shader color image slot. No specular image in reflectivity slot, roughness image connected to roughness function. No displacement image in displacement image slot, 'bump' image connected to displacement function.

Example C:  Dual map use in Specular and Displacement. Albedo in default shader color image slot. Specular image in reflectivity slot, roughness image connected to roughness function. Displacement image in displacement slot, 'Bump' image connected to displacement function.

Example D:  Same as Example C except for higher displacement multiplier: .67 to 1.5. Higher multiplier on       Example A distorted the texture.


zaxxon

attached the wrong image above, damn... I did say I had damaged some brain cells though.

DannyG

#24
This is great for the objects, has anyone had any luck with Substance Designer or Megascans ground materials? Here's a material exported from SDesigner. When I load it into a default shader in its appropriate areas, I personally can't get it to look usable. I know J Meyer posted some time ago a simple node network with a dry earth megascan 3d scan. That particular one worked fine and Some do seem to work, however other more complex ones just don't. So in the interest of time I tend just to revert back to using it as a simple image overlay repeating on XY call it a day. Anyone ?
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Dune

I think I used the AO to mask a surface shader under the default with a color adjust as child.

j meyer

That's what I get out of it on the fly.
[attach=1]

Tgd attached. Make sure to look at the 'colour' tab settings of the 'Height' image map shader.

You don't need the 'metallic' and 'normal' images in TG.

DannyG

Quote from: j meyer on January 23, 2018, 01:32:26 PM
That's what I get out of it on the fly.
[attach=1]

Tgd attached. Make sure to look at the 'colour' tab settings of the 'Height' image map shader.

That was the difference right there Joe, This looks very good, Thanks Bud!
I exported them at 4096, See attached
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archonforest

Just downloaded a test rock with textures from Quixel. Tried in Blender and it worked okay. Tried in TG and...huh nothing. Can someone tell me to where to plug the albeido texture with what settings? I tried pretty much everything but no luck. Seem I miss something elemental...
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Oshyan

Albedo is basically the same as diffuse, color, or "base" texture. It can go into the Colour Image slot of a Default Shader. But if you are not getting any materials loaded in when you bring the OBJ model into Terragen, unless it's a very simple object without UVs, then it's probably not something you can just fix in Terragen. The source application (Quixel in this case) needs to provide material groups that correspond to UVs of the model and Terragen will turn those into "Parts Shaders". Without those your textures will normally just apply to the entire object, so even if you successfully loaded an Albedo/Diffuse texture, it might not apply the way you want/expect it to.

In Blender are you importing an OBJ? Does the OBJ have a MTL file with it?

- Oshyan