Handling indirect lighting

Herald of Fire

Really this thread is about what options I may have available to perform this feat under Daz Studio. So far, my dabbling with IDL has been restricted to creating a simple shader camera with an IDL brick. As inception said, "We need to go deeper".

The reason I brought this up is because I was working with Maclean's apartment, a recent purchase of mine which I utterly adore. When walls naturally get in the way of the light, it becomes more difficult to flood the scene properly without using shadowless lighting. The catch there is that it causes all sorts of nuisances with subsurface shaders.

Now, I could flood the scene with a dozen advanced ambient lights and the like, but I want the lighting to be as close to natural as possible, either (apparently) lit by the single bulb in the room or by the sunlight streaming in through the unblinded windows. Therein lies my challenge.

The obvious solution would be to simply use Luxrender, but I want to keep the 3DL shaders and style so I'm looking for some good IDL options. What I'm requesting might seem like a tall order, but I know that the engine is capable. I just haven't figured out how to pull it off properly yet.

Lissa_xyz

Is something like this what you're after?

If it is, what I did is use an AAL on diffuse only at 100% intensity and set the radius to 0 (setting it to 0 turns it to a global fill). Then I added an Advanced Distant Light at about 175%+ intensity and left it as 'on'. I also changed the color to a soft yellow. The AAL acts as a room fill, while the higher intensity distant gives that sunlight effect.

With the distant, I also set it in the sky at a downward angle, and then use y-rotate to place it to whatever windows I want the light shining through.

SimonJM

An 'Ambient Diffuse'? Confused by that term - what sort of light is that?

Lissa_xyz

Sorry, Advanced Distant. Don't know why the hell I called it an Ambient Diffuse. o_O
http://www.daz3d.com/advanced-daz-studio-light-bundle

I've corrected my original post.

SimonJM

Vaskania said:

Sorry, Advanced Distant. Don't know why the hell I called it an Ambient Diffuse. o_O
http://www.daz3d.com/advanced-daz-studio-light-bundle

I've corrected my original post.

I guessed that was what you meant, but wanted to be sure :) I have moments like that. I call it life ;)

Herald of Fire

I was hoping for a method which didn't require using global fills. I know there are workarounds, but the problem with global lighting is that it affects all things equally, even areas which you may want intentionally darker. That's partly why I'm looking for a decent IDL. That way the light still doesn't travel through walls, but it provides enough ambient lighting to make things look believable.

Richard Haseltine

You can use AO to shadow corners - just make sure the Trace distance is low enough that the whole room isn't shadowing itself. You can also use UE2 in Bounce (GI) mode, with spot light, area lights, or simply a high ambient strength and light ambient colour on your light sources (though keeping noise down can be tricky).

Lissa_xyz

Here's one I did with the same AAL and Advanced Distant setup. The difference is that the AAL is set to Light Radius: 5, Falloff 100%, and Intensity is down to 50%. You get similar results using the UE GI Bounce except the render times hit the roof depending on your quality settings.

Lissa_xyz

Just for completion sake, here's the same shot (roughly) set up in Poser using an EnvSphere by Bagginsbill with a daylight map and IDL.

AndyS

Hi Herald,

please have a look at what I posted here: --> http://www.daz3d.com/forums/discussion/42024/
or here. http://www.daz3d.com/forums/discussion/35443/

The secret is as follows:
Each ray once shadowed isn't allowed to get alive again. --> ray trace max = endless (=0) for UE2 with indirect lighting (IDL).
Each window is a source of diffuse natural daylight. So: UAL in each window.

If you have any question, please don't hesitate to contact me.

yours
Andy