Homogeneous volume absorption depth

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wasd
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Re: Homogeneous volume absorption depth

Post by wasd »

Dade wrote: Thu May 17, 2018 11:32 pm
You are confusing object transparency (or opacity if you prefer) with object surface+volume. Transparency makes all object (surface+volume) transparent, like with alpha channel. In your case must be set to 0, it is not what you are looking for.

The object material describes the surface (i.e. the "skin") of an object while volume describes the interior.
So what? You just don't want to see the pictures I attach. Look, the objects are completely white (it's the "Transmission color", I've tested it) . This is not how they should be.
And now for what I expected to see:
Скриншот 2018-05-18 09.36.42.png
Not some transparency or whatever.
But with a slightly different angle I see this:
Скриншот 2018-05-18 09.39.37.png
Somehow this doesn't happen to objects in example by B.Y.O.B.
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B.Y.O.B.
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Re: Homogeneous volume absorption depth

Post by B.Y.O.B. »

I can reproduce a weird view-dependent effect in your scene.
https://youtu.be/oDtza9dQTYs

edit: I have check if the cause is this bug: https://github.com/LuxCoreRender/LuxCore/issues/106
But even with a pyluxcore from the v2.0.x branch the problem appears.

It also happens with sun+sky instead of an HDRI.
I opened a github issue: https://github.com/LuxCoreRender/LuxCore/issues/113
wasd
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Re: Homogeneous volume absorption depth

Post by wasd »

B.Y.O.B. wrote: Fri May 18, 2018 6:09 am I can reproduce a weird view-dependent effect in your scene.
https://youtu.be/oDtza9dQTYs

edit: I have check if the cause is this bug: https://github.com/LuxCoreRender/LuxCore/issues/106
But even with a pyluxcore from the v2.0.x branch the problem appears.

It also happens with sun+sky instead of an HDRI.
I opened a github issue: https://github.com/LuxCoreRender/LuxCore/issues/113
Don't know it will help, but I (suddenly!) remembered that this scene and materials was probably made originally with old lux, so I cheked that and found that that material has also old lux nodes.
Скриншот 2018-05-18 14.50.29.png
So I made new scene, added material in old lux, then switched to new, added nodes, but could reproduce the effect.
p.s. that means I can return to my grass, because double-sided glossy translucent actually works, though, not every time maybe. Thank you.
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Re: Homogeneous volume absorption depth

Post by B.Y.O.B. »

wasd wrote: Fri May 18, 2018 8:23 am Don't know it will help, but I (suddenly!) remembered that this scene and materials was probably made originally with old lux, so I cheked that and found that that material has also old lux nodes.
That is not a problem, they will be ignored.
wasd
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Half-lawn

Post by wasd »

I still can't finish this picture with grass and trees :(
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grass-bug2.png
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Fox
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Re: Homogeneous volume absorption depth

Post by Fox »

Can you use heterogeneous volume?

Homo volume 10 min render
Image

Hetero volume 10 min render
Image
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