Query about the realistic rendering demo...

This is a question about the realistic rendering demo and the four spotlights that are used to bounce light around the interior

As far as I can see, none of the four lights appear to cast any shadows despite having their ‘cast shadow’ setting switched on.

I’ve attempted to do something similar in one of my own scenes, but with multiple spotlights I end up having multiple shadows. I’ve more or less used the same spotlight settings.

I don’t want to switch cast shadows off…any ideas?

Check out the source radius and cone values. Those are the things that affect shadow sharpness the most and combining them with very low light intensity(.05 for those spotlights in realistic rendering) can give you that ambient lighting look.

Yep, from what I gather, super high cone values spread the light out as opposed to low values which focuses the beam of light. I’ve played around with the source radius and tried values from 0 - 100. Spotlight intensity set to 0.005 or 0.01 and I still end up with something like this:



You can still see the ring of shadow caused by the spotlights.

View from the outside:


I do have a lightmass importance volume in there as well.

Those shadows arent as noticable in realistic rendering because there is also the directional light entering through the wingows, and because of the way the lights are positioned. If you select the lights you’ll see that their outer cones are barely inside and there is a 10 unit difference between the inner and the outer cone angles. Looking at your first screenshot, if you move the lights a bit inside the room so that the cone doesnt intersect with the wall will help, but it wont be perfect without directional light support. So you should consider using a “hidden” reflective mesh outside the windows like you see in Koola’s project.

Yeah I definitely thought that was one of the reasons why the shadows didn’t appear in the realistic rendering demo - because the directional light was stronger and washed out any of their weaker shadows. And the fact that the window is full sized from floor to ceiling which makes things much easier.

Koola’s method is interesting but a little bit tricky for my situation. Koola and others who use the reflector method can get away with it because their visualisations are purely interior. Unfortunately the exterior is also explorable and you can see some backwash on the outside from the reflector.




I’ll try and ram the reflector right up against the window and cover it up entirely but I’m not very optimistic. I’ve already had to shrink the cones down so that they fit onto the reflector and don’t shine onto the ground. I’ll see if maybe two weaker spotlights on the one reflector helps.

Okay so I forgot about this thread but I’ve fixed the problem.

Placing reflectors right up next to the windows works but then you get the halo lights caused by the spotlight on the outside as you can see.

Instead of doing that, I got rid of the spotlight completely and used the directional light to illuminate the reflectors instead. I placed the reflector a good distance away so it catches the directional light. This + the residual light from the directional + the skylight is enough to give nice soft ambient lighting in the room


Just posting for anyone in the future that falls in a similar situation.