How to set volumetric lights ?

[Ezz]

Hello

Its fairly easy...

get your light. point, spot etc...then "Render" - "Property" - "Volumic" and there you go....
Remember to make the light cast shadows to achieve the affect you are after...


Erik

[MorBioS]

And how can I add noise on volumetric light?

Thank
:)

[dg]

Fala MorBios!!!

Feliz Ano Novo Velhinho :D

Enable shards in the Shards tab, and play with intensity, scaling and complexity, this might give you the results you want, if not tell me and I'll try to help you better.


See ya!

[MorBioS]

pa Diogo blz? :)

Ok thanks. I did see that parameters. I'll play with it again.


Thanks DG

[Putois_Blagueur]

It doesn't seem to work...

I did what you told me, but I still can't see the light cone...

Is there a specific option to check in the render options ?

[SheepFactory]

make sure you have the spotlight selected before you apply the property -> volumetric.

there is no opetion to check other than the "active" checkbox in the volumetric property editor. it'll show up as soon as you apply in the render region.

[SheepFactory]

Morbios , as far as adding noise goes , why dont you render the volumic pass seperately and add the noise in post?

[Putois_Blagueur]

Sorry, in fact it works well, but I was using an infinite light, and it seems not to work with that type of light. Is there another way to make an infinite light to be volumetric ?

[ThE_JacO]

a volumetric light needs a volume to raymarch the shader in, no other lights but spotlights have a defined volume to operate in.

if you need sort of parallel rays pur the spot very distant and use the start and end falloff options to avoid useless computations of the whole cone.

[MorBioS]

Originally posted by Sheep Factory
Morbios , as far as adding noise goes , why dont you render the volumic pass seperately and add the noise in post?

ok thanks but Sheep Factory :)

But I mean 3d noise like smoke in volumetric light. something like texture in volumetric light will be very fine.
anyway I don't know how work with post in xsi yet. I'm learning xsi slowly :)

thanks

[roboboy]

Hey Morbios,
I usually use a different approach - might work for you. I'm going to go step by step - sorry if it's too wordy.
Create a new scene. Then go the the main control panel on the right and go to Explore>Current Pass and click on the icon next to Default Pass in the popup. A property panel should pop up with several tabs. Go to the Volume shaders tab. Click add and select the Volume_effects shader in the popup. Now select it in the list and hit Inspect. Lock down the Volume effects property page that pops up so you can experiment with the settings.
Now, draw a render region and add a point or spot light to the scene. With point lights you need to enable falloff and keep the values low such as start falloff = 5 and end falloff = 30. Click on the lights tab within the volume effects PPG and add your new light to the scatter and shadow light lists. Also, in the Scattering tab you might want to bump up the ambience a bit and take the density down until the fog is the right thickness. There's also a fractal tab where you can edit the noise values of the fog.
Edit your light to cast shadows and take the umbra down to zero or just above. Now, you should be able to move your light around and see noisy smoke and volumetric shadows if objects occlude the beam. Just remember that the lights you want to calculate in the fog must be added to the lists in the light tab of the volume shader.
The advantage to this method is that spots or point lights can be used. Also, you can get very cool effects with point lights with short falloffs and intensity values above 1. Hope this helps - good luck.

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