dark juice

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Fox
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Re: dark juice

Post by Fox »

FarbigeWelt wrote: Thu Aug 22, 2019 5:28 pm If you increase scattering less light passes the volume and volume caustics disappear completely.
You are right, thx for tip.
I test the textured volume between:
1. Low forward scattering and low absorption volume (caustics are all there)
2. The original volume

Question is how to get good mix.
Fox
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Re: dark juice

Post by Fox »

Well now it's pretty sure there is orange transmission in shadow. But it's slow, even though volume step size is large 3cm and max steps 128.
Textured hetero volume.jpg
Fox
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Re: dark juice

Post by Fox »

I don't think it's mostly SDS path issue. The only way to get colored transmission, that is not very dark shade, is lowering absorption, or making volume thinner. But it does not look orange juice anymore.
The colorless transmission comes only from glass mesh top, bottom and sides, not through juice.
S0rda
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Re: dark juice

Post by S0rda »

a juice object inside a glass object? This is not true. You need to do this in one mesh. Polygons that are joint for juice and glass will have a refractive parameter equal, it seems, to the result of the division of the refraction of glass and the refraction of juice. Or vice versa.

In addition, you can only imagine how many unnecessary calculations are forced to render when calculating light in space (and it will be anyway) between these two objects.
Fox
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Re: dark juice

Post by Fox »

S0rda wrote: Thu Aug 29, 2019 10:45 pm a juice object inside a glass object? This is not true. You need to do this in one mesh. Polygons that are joint for juice and glass will have a refractive parameter equal, it seems, to the result of the division of the refraction of glass and the refraction of juice. Or vice versa.

In addition, you can only imagine how many unnecessary calculations are forced to render when calculating light in space (and it will be anyway) between these two objects.
Null material for juice body is so much faster. I have mix of null and glass, the result doesn't look unrealistic. I guess it's not totally incorrect because heavy scattering and in real life there is ton of larger particles of fruit pulp pressed against glass walls. You have all kind of ior's in vegetation from 1 to 4.
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lacilaci
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Re: dark juice

Post by lacilaci »

Fox wrote: Thu Aug 29, 2019 11:59 pm
Null material for juice body is so much faster. I have mix of null and glass, the result doesn't look unrealistic.
Are you talking about this result?

Image

Cause this is definitely not orange juice.

here
Image

Anyway, I thought it is by now pretty clear that glass is in such cases extremely limiting in luxcore, can't do transparend shadows and luxcore can't do sds yet, so your only option is stay away from stuff like orange juices...

Not only that, but something like pool water is not doable as well, even if I would be ok with not getting caustics, the volume simply isn't getting light through the glass shader so everything inside pool wil be very dark (So in case like that even cycles does more realistic job than luxcore cause it at least let's light through)

We need to wait for this: viewtopic.php?f=5&t=1369 and it would be really useful to have hybrid glass as an option on top of that! Then we can do anything that's doable with glass in other renderers and also SDS caustics on top of that.
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FarbigeWelt
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Re: dark juice

Post by FarbigeWelt »

Fox wrote: Thu Aug 29, 2019 11:59 pm ... because heavy scattering and in real life there is ton of larger particles of fruit pulp ...
If you unterstand what you said there you some steps closer to a possible solution for orange juice.
... still, ongoing optimizations running ...
... still, ongoing optimizations running ...
Materials used: Glass ior glass, Glass ior water, Null homogeneous volume
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Fox
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Re: dark juice

Post by Fox »

Just to clarify, when i used null, there was far less noise, but the juice did not look far much different.

The original gamma-1 hdr map is very high contrast 24EV, shadows are pure black in linear tonemapper. I used 2'th copy of hdr with gamma 0.8, that's why there was light in shadow that killed orange caustics.

Here are the first images where i used null material mix 50/50 with glass for the juice body.

See the dark shadows even though heavy shadow lift with reinhard
prescale = 0.34999999403953552
postscale = 7
burn = 20

This is the real hdr with gamma 1, no fake 0.8. The shadow is not polluted with other light sources.
gamm1 layer.jpg
This one is with gamm 1 + gamma 0.8
gamma1 + gamma0.8.jpg
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FarbigeWelt
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Re: dark juice

Post by FarbigeWelt »

Fox wrote: Fri Aug 30, 2019 12:15 pm
gamm1 layer.jpg

gamma1 + gamma0.8.jpg
I like your pictures, they are pretty close to orange juice. Scattering or absorption or both might be slightly stronger and a bit more to red just a little bit like e.g. r,g,b 1,0.85,0.075.
Defining color of juice by color of Null and absorption color of volume as orange and scattering as white might be worth a test.
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tokiop
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Re: dark juice

Post by tokiop »

Indeed, nice beverage Fox ! With a mint leaf or citrus it would look geat..

Maybe we can switch to drinking something else than orange juice while waiting for LuxCore's next juicy features ! Orange juice has too much sugar anyway.. :lol:
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