GI / Indirect light

stem_athome

Hello,

I have been trying to set up a simple scene with Global Illumination / Indirect light. I have been searching the forum, but links for information either go to the old forum(archive) which is offline, or go to the online docs, which when looking for "Indirect light" only shows you a picture of the mixer brick. As the "Indirect light" doc entry linked to the "Area light" I looked at that, which again only shown a picture of the mixer brick used, it did have a link at the bottom of the entry for an example, but the link for the example lead to a "Not found" page.

So I was hoping there is some information that is accessible and gives enough information to be able to apply global illumination/indirect lighting to a Daz studio scene.

Thanks.

Richard Haseltine

The simplest way is to use uberEnvironment 2 - set the mode to one of the Indirect Light options or to Bounce (GI), adjust the quality (using the presets in the folder with the light or by tweaking the settings) and add the light sources that are going to bounce.

Richard Haseltine

It's not a terribly good example, but this is Provence with a single distant light for the sun and uberEnvironment 2 set to Bounce mode (it's the Bounce light from the light itself, with no settings changed).

stem_athome

Hi Richard,

Many thanks for the reply.

Sorry, I should of been more specific. The actual scene I want to render is in an enclosed space (a vault with no windows). I did look at the uberEnvironment 2, but it appears to be based on a light dome/sphere. I did try various options with various lights within the vault, but found the results similar to photon mapping with too large a search radius, which made light leaks through the vault walls. Other settings gave no Indirect light (probably because it is based on outside scene? or an inside scene with windows? I do not know)

I looked at the "UberAreaLights" but they do not appear to render Indirect light.

I changed to a simple test scene to try and work out how GI/Indirect light actually works in Daz studio, so was looking for information, but links found are dead. So posted to see if anyone has information or links to such information.

Richard Haseltine

In most of its modes uberEnvironment is using an HDRI map as a light source -the sphere is there solely as a visual guide, it isn't a functional part of the light. There is a setting Maximum Trace Distance that controls how far it looks when determining occlusion (if you have selected one of the occlusion options) and bounce - if your enclosed space was coming out dark that probably means it was smaller than the trace distance and so was completely occluded (while my render above was prrly lit because the trace distance was too low to reach the sky dome). I made two more renders, from a different viewpoint as I lost the original; one has the trace distance turned up far enough to reach a (shrunken) Provence skydome, the other uses a second UberEnvironment 2 with the trace distance deliberately turned way up so that the buildings were occluding and preventing light from coming in from the light at angles the sky wouldn't have reached - the original render took about fifteen minutes, the increased trace render took about eighteen, and the double UE2 took about twenty-five (but I had turned the occlusion samples up to try to reduce the increased graininess from the two lights - though none of the renders would be acceptable as a final image); all renders were done using the progressive render option, which can be faster for intense calculations but does seem to make noise more noticeable.

stem_athome

Hi Richard,

Richard Haseltine said:

In most of its modes uberEnvironment is using an HDRI map as a light source

Again, thank you for the reply.

But that is an external light source, I do not want external light entering an enclosed space.

Not to worry, I have now found how to set it up. Like anything else, very simple once you know how LOL.

stem_athome

Ignore this post.

Found the advanced brick settings, so now OK (well I think so lol)