YafRay sunlight indirectly-lit room?

I’m trying to set up a room lit entirely (or at least appearing to be entirely) lit by indirect sunlight coming from one window at the end of the room. I want the sky/outside scenery visible through this room to be visible through this window, however.

In my renders, I’m just using the default material for the inside of the room, and I can see a bit of ambient light on the walls and ceiling (the sun lamp hits the floor), but not very much.


Basically, I want there to be a visible “square” on the floor from the sun coming in from the window, but I want the whole hallway lit up from the ambient light from the sunny day outside, if that explains it at all. I’ve tried to do this with one large area light, but the light attenuates too much and is too bright at the source. Should I try to place several small area lights to get the desired affect? I want some realistic looking shadows cast as well… hrm.

Can you post pics of your work so far ? I think it is the best way to lock people into answering you…

As long as you don’t add glass, a sun lamp and GI will do the trick. You could also go the area lamp/photon route by adding the emitter at the window.

I’ll post some pics tonite or tomorrow. I think using an area lamp is going to be the way to go, but it too attenuates too much… grrrr
I tried just a sun lamp and GI, but there’s not enough indirect light coming from the reflection on the floor, is there a way to turn this up? – is this GI intensity?

In theory, shouldn’t there be two light sources? One sharp light coming from sun, and one indirect light coming from atmosphere? How/should I accomplish this?

Sun lam and GI. Tune via GI panel (emit values for light and GI intensity for GI)

Masterhoshi answered the first part so I might try myself on this one.

True, and actually there are two lightsources. There is not specific “indirect light” which you could add like a spotlight or an arelight or something - when you enable GI, the World background automatically acts as that indirect source of light. That obviously means, that its color affects the color of the indirect lighting. A black world will not illuminate anything while a blue-ish sky will give you a blue-ish lighting, just as you might need it for a sunny day or something.

Its remarkable easy to do this type of light setup in indigo…
just a suggestion.