Can't get any volumetric light

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FrancisJ
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Can't get any volumetric light

Post by FrancisJ » Mon Sep 09, 2019 9:25 pm

Hi there,

I'm new to LuxCoreRender,

I try it for a 6-7 hours already and I'm having a lot of fun.

I wanted to make a volumetric light. I have search on the net, read the doc etc... But I still can't get any volumetric light in my render.

For my final scene, I would like to have something like that...

Image

Here my test scene, as you can see, I'm having no volumetric light in my render.

Any idea ?

Thx a lot !

Image


http://img.zeden.net/voir/2bb8b3dffd077 ... 87f7b95270

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B.Y.O.B.
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Re: Can't get any volumetric light

Post by B.Y.O.B. » Tue Sep 10, 2019 3:42 am

Can you upload your testscene?
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FrancisJ
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Re: Can't get any volumetric light

Post by FrancisJ » Tue Sep 10, 2019 5:44 am

Sure, sorry I should have done that first.

I'm using Blender 2.8 base version,
I'm using BlendLuxCore-v2.2beta4-blender2.80-win64
I have a generic I5 + Gtx 1060
Attachments
Volumetric_Light.blend
(818.94 KiB) Downloaded 16 times

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Dade
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Re: Can't get any volumetric light

Post by Dade » Wed Sep 11, 2019 1:56 pm

FrancisJ wrote:
Tue Sep 10, 2019 5:44 am
Sure, sorry I should have done that first.

I'm using Blender 2.8 base version,
I'm using BlendLuxCore-v2.2beta4-blender2.80-win64
I have a generic I5 + Gtx 1060
Ok, you have not declared correctly inside/outside volumes for the objects so the scene is rendered like if there was not volume at all.

The simpler solution is to delete the NULL volume box in your scene and just set the world volume. This will tell LuxCore that the volume where the camera is (aka "air"), the one with scattering. The result will be:

dust.jpg

To fix your scene set up, you need to set outside volume of the sphere: your scene relay on camera auto-volume detection, it will trace a ray, hit the sphere and set the volume (after the fix, it is currently not set).
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FrancisJ
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Re: Can't get any volumetric light

Post by FrancisJ » Thu Sep 12, 2019 9:53 pm

Hello !

I have try a bit more (1 hour) to get any volumetric light in a simple scene.

I tried to have volumetric light with the world setting as you told me (luxrender).

In Cycle, it work easily, I just set a Principled Volume to the word, reduce the density and voila !
In Luxrender, I can't get any volumetric light with the world setting, as you see in the picture below...Is that a bug ?

Image

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Dade
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Re: Can't get any volumetric light

Post by Dade » Sat Sep 14, 2019 2:29 pm

@B.Y.O.B.: is there a problem in BlendLuxCore for V2.8 ? The world volume property is not exported (and the referenced volume too). It may be a problem in the FILESAVER engine (but I think it was working in v2.79).
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Re: Can't get any volumetric light

Post by B.Y.O.B. » Sat Sep 14, 2019 3:26 pm

I fixed a bug in world volume export three days ago: https://github.com/LuxCoreRender/BlendL ... fbd8b39d3b
Do you have the latest sources?
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Dade
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Re: Can't get any volumetric light

Post by Dade » Sat Sep 14, 2019 7:20 pm

B.Y.O.B. wrote:
Sat Sep 14, 2019 3:26 pm
I fixed a bug in world volume export three days ago: https://github.com/LuxCoreRender/BlendL ... fbd8b39d3b
Do you have the latest sources?
I don't but I assume FrancisJ doesn't too because he is using beta4.

@FrancisJ, you need to update to the latest BlendLuxCore that, thanks to Acasta69 works, it is now available here: https://github.com/LuxCoreRender/BlendL ... tag/latest
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FrancisJ
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Re: Can't get any volumetric light

Post by FrancisJ » Sat Sep 14, 2019 11:13 pm

Great, the world volumetric is working now !



I have try to understand volumetric light for like 6 hours, so I think I found another bug...

Here is another bug...With the world setting the caustic is behaving as I think it should, as I just try it

Image

But when I make a box with a volumetric inside volume, it's behaviour is really weird...
The volume setting are the same, as I just copy/paste it
As you can see, there is no volumetric caustic whatsoever... And I always got that, so matter how hard I try to tweak the setting.

Image


There is a box with volume (same one)...But without the floor.
It has some kind of caustic, but not as good as with the world setting.

Image


I don't think I need to link my scene, as it's really easy and fast to build one yourself and see if you have the bug

Cheers,
Francis

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B.Y.O.B.
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Re: Can't get any volumetric light

Post by B.Y.O.B. » Sat Sep 14, 2019 11:17 pm

The images don't load at my end, can you attach them to the post?
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