Laci's wip

Post your tests, experiments and unfinished renderings here.
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Dade
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Re: Laci's wip

Post by Dade »

lacilaci wrote: Tue Apr 02, 2019 11:40 am
Dade wrote: Tue Apr 02, 2019 11:07 am Is the wall made of Glossy material ?
Yes, the problem is only appearing on glossy material
What kind of material do you use with Cycles ? I assume the black border is the result of too Lux glossy specular component and not enough diffuse componente.
I'm not happy of current status of LuxCore materials but it is somewhat the topic of v2.3 release so I tend to postpone any not urgent material related topic for v2.3.
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Re: Laci's wip

Post by lacilaci »

I understand. And I hope at 2.3 this issue can be somehow resolved.

Anyways, in cycles I used their principled material(used very glossy values aswell!), I use it for anything as there is no reason to use different materials. It never fails to provide good reflections at grazing angles, the only 2 missing things in cycles's princibled material to make it perfect are microroughness controls and iridescence but otherwise it is pretty much all you need most of time at least.

On other hand luxcore glossy shader seems to be a bit limited compared to principled shader, but also very close to usability for many common architectural materials. However the darkening edge on the material I experience over and over again and while it is mostly notable on large areas like walls, I guess it is also affecting all other objects(floorboards, larger furniture pieces etc are always lacking grazing angle/edge highlights)... As I said, the very same issues were happening with corona and it took some while to fix, so maybe instead of fixing this now it might be worthwile rather making some new ubermaterial that also avoids these problems.
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Re: Laci's wip

Post by Fox »

Can PhotonGi benefit from importance sampling from grazing angles?

If you have surface like that:
Surface like that.png
Viewed at this angle
View Angle.png
It tends to render black, no matter what material.
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Re: Laci's wip

Post by lacilaci »

Fox wrote: Tue Apr 02, 2019 6:36 pm Can PhotonGi benefit from importance sampling from grazing angles?

If you have surface like that:
Surface like that.png

Viewed at this angle
View Angle.png

It tends to render black, no matter what material.
I don't know about photongi, this issue was present before photongi.. But cycles can avoid material darkening at grazing angles even with 1! bounce of light and heavy bump map.
Maybe it's a workaround, maybe it's a better shader. I don't care. cycles solution works and luxcore fails very badly that's the result!

I'm pretty sure dade can do better than cycles devs, at this point in time it is clear to me... The question was, is there a fast fix we can use now, or do we wait for new (2.3) type of material that compensates for bump/normal mapping and reflections etc...
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Re: Laci's wip

Post by Dade »

As far as I remember Cycles glossy is based on GGX model, Lux glossy(2) was written a lot before GGX was even invented :mrgreen:
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Re: Laci's wip

Post by kintuX »

lacilaci wrote: Tue Apr 02, 2019 10:56 am ...I also found an issue that I mentioned on these forums a while back.

It's darkening on shaders at grazing angles, an issue that was some time ago also present in corona. It is not present with cycles. Can this be fixed with current shaders or will this be fixed in the future? It looks terribly.

luxcore:
luxcore.jpg
cycles:
cycles.jpg
Could you point to its location? Is a test file present?

I just can't replicate it here :?:
GlossDarkEdge-001.jpg
GlossDarkEdge-002.jpg
Default Sun&Sky, Deafult Glossy (Orange Color), Default OCL, Default PhotonGI Cache... scene attached:
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GlossDarkEdge.blend
(152.42 KiB) Downloaded 131 times
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Re: Laci's wip

Post by B.Y.O.B. »

kintuX wrote: Wed Apr 03, 2019 12:17 pm Could you point to its location?
It's the wall on the left edge of the images.
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Re: Laci's wip

Post by kintuX »

B.Y.O.B. wrote: Wed Apr 03, 2019 12:33 pm
kintuX wrote: Wed Apr 03, 2019 12:17 pm Could you point to its location?
It's the wall on the left edge of the images.
Yes, i've noticed that. Took a shot with camera in approximately same angle. ;)
I was meaning its previous post mentioning the issue - if there's any more description and if file is present.
Sorry if i was unclear about it.

PS
The scene attached is trying to replicate both his scenes. Glossy material is on the walls and on the deformed sphere, but nowhere dark edges occur.
I don't wanna assume nothing further, until i take a look at the real thing - the scene file.
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Re: Laci's wip

Post by lacilaci »

Very interesting.. So I've figured there was a shading issue, autosmooth + bevel modifier changed shading and that resulted in the error.
The interesting part is that this type of shading issue doesn't seem to affect cycles at all. This is frustrating
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Re: Laci's wip

Post by Dade »

lacilaci wrote: Wed Apr 03, 2019 1:10 pm Very interesting.. So I've figured there was a shading issue, autosmooth + bevel modifier changed shading and that resulted in the error.
The interesting part is that this type of shading issue doesn't seem to affect cycles at all. This is frustrating
So was it normal interpolation related ?
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