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sellis
03-17-2018, 01:56 PM
Does any one know how to cast shadows within a volumetric light in 2018?
140714
Cast shadows is checked but doesn't seem to work.
I can't find any control for the size of the volumetric, other than the light intensity!

Thank you..

prometheus
03-17-2018, 02:23 PM
Does any one know how to cast shadows within a volumetric light in 2018?
140714
Cast shadows is checked but doesn't seem to work.
I can't find any control for the size of the volumetric, other than the light intensity!

Thank you..


We need a description of the scene you have set up, only that you have a light setup with a screenshot of it doesnīt illustrate anything than your settings.
Post a screenshot of the scene and what kind of object there is that is supposed to obscure the light and cast shadows.

The size control is right there in the light tab for the spherical light(basic tab, in the bottom where you have samples, MIS samples etc.)

Volumetrics is mostly controlled by the Global volumetric scattering integrator, in the volumetrics tab, and getting shadows to be cast may depend on how close you have your light in relation to the object that is obscuring it, if the light is too far away, the shadows may not be very distinct.

sellis
03-17-2018, 02:33 PM
I was only seeing how instances with the new lighting worked...

140715

Here is an image with the settings from previous...
Clearly I am missing something!

Cheers

prometheus
03-17-2018, 02:44 PM
I was only seeing how instances with the new lighting worked...

140715

Here is an image with the settings from previous...
Clearly I am missing something!

Cheers

the new lights, volumetrics is working on instances, at least on 2018.01 havenīt installed 2018.02
there is a light that doesnīt work with volumetrics, such as distant light, but the spherical light you have should be working, but.....volumetrics is a bit complex to get working all over the scene or realistic as a true sunlight and with instances it depends on how far your light is from the instances, try to grab the spherical light and move it close to one instance and behind it and see if that takes effect, if it works then it should be a matter of raising scattering density, there is also the lights own volumetric intensity which you could cranck up high...and instead lower the actual light intensity, then you got the scattering assymmetry, I would recommend a value of 0,5-0,8

sellis
03-17-2018, 02:47 PM
Thank you Prometheus. Will try your suggestions.

Cheers

prometheus
03-17-2018, 03:03 PM
Thank you Prometheus. Will try your suggestions.

Cheers

keep in mind that getting cast rays in a scene with lots of objects scattered at distance, that is very tricky when some objects are at distance and some are reaching closer to cam, and having a light can not be close enough to all those items, and if you have a light source that is huge, it will overblow the whole scene so the cast rays will be almost non existent.

I would suggest try from scratch with just one object and make the light and the rays work behind that object, then make an instance of it and move it slightly to the side and check that it works, then start moving the actual light back to see how the raycast effect will simply not work anymore.

Thereīs also a tree volumetric scene in the content that you could mess around with, change light type, change volumetric intensity, scattering intensity and assymetry., move cam around etc.

sellis
03-17-2018, 03:10 PM
Good thinking. I'll try that.

Thank you.

gerry_g
03-17-2018, 03:49 PM
find spotlight is good for this as it is a very smooth light, area lights are the worst as they are grainy, don't crank up the light lux intensity or you will get fireflies, as stated by Mr P crank up volumetric intensity as in thousands it goes way beyond hundreds

sellis
03-17-2018, 04:19 PM
140722

Thanks Gerry.

No matter what I did with the spherical light, I couldn't get shadows.
The spot light has produced them. I had to turn down the light intensity to 3lx and it reduced the render time by 2/3rds!

Also I get to see more depth into the image but that may be the reduction in light intensity.

I assume then the spherical light can't cast shadows?

prometheus
03-17-2018, 04:30 PM
140722

Thanks Gerry.

No matter what I did with the spherical light, I couldn't get shadows.
The spot light has produced them. I had to turn down the light intensity to 3lx and it reduced the render time by 2/3rds!

Also I get to see more depth into the image but that may be the reduction in light intensity.

I assume then the spherical light can't cast shadows?

no spherical lights can cast shadows, they just need to be very close to the object that should obscure it.
make sure you have raytraced shadows on in the render panel

sellis
03-17-2018, 04:38 PM
Yes, raytraced shadows is on.

Thanks guys. Just testing things.

Cheers

jwiede
03-19-2018, 08:58 PM
After playing around with a quick test, I realized VPR showed them even though OGL did not.

prometheus
03-20-2018, 01:43 AM
After playing around with a quick test, I realized VPR showed them even though OGL did not.
Open gl has never been able to display volumetric lights.
Vpr has always been able to render old volumetric lights..and now new

sellis
03-21-2018, 04:53 PM
More testing... recreating as opposed to saving and converting scene. The position/perspective of object is different between 2015/2018 even though camera and object positions are the same.
140816
Is it just me?

The box in both versions was created via Layout model tab.
Pivot point maybe?

prometheus
03-22-2018, 12:25 PM
More testing... recreating as opposed to saving and converting scene. The position/perspective of object is different between 2015/2018 even though camera and object positions are the same.
140816
Is it just me?

The box in both versions was created via Layout model tab.
Pivot point maybe?

odd..it might be the pivot point, I can not test since canīt create in discovery mode, but I think I have a vague recallection that lw 2018 changed pivot origin for layout created objects, make a cube from scratch in modeler, and load it in to the scene and test it, use the same object for the two layout versions.