View Full Version : GI & Radiosity Head Scratching

08-06-2005, 08:48 AM
Afternoon all.

Trying to improve my lighting in scenes, so i have knocked up a simple box room with a window, and a lovely red ball in it for good measure.

I have an area light pointing diagonally into the room from outside the window with radiosity on.

Now the question is, how do i get the light to shine on the floor from the outside? (i.e, the window frame shadow on the floor surrounded by a shaft of light)

Ive fiddled with the light options but its not having it.

Can anyone point me in the right direction, i can't find any tuts on room lighting. Is area lighting the way to go?

Attached an image so you get the idea.

Cheers :)

08-06-2005, 10:34 AM
To get shadows you must either enable ray-traced shadows in the Render panel, or use a spotlight with shadow maps (Light properties=>shadows panel).


08-06-2005, 10:48 AM
Also, if you want a "shaft of light" to be visible, that's called "volumetric lighting", which can be enabled in the Light properties panel.


08-06-2005, 01:43 PM
Id say its an improvement, shame about the 1hour 30 rendering time :confused:

Anyway, cheers Monroe, just what i was looking to do :D

08-06-2005, 02:12 PM
Are you rendering with monte carlo radiosity? Because to speed things up (at the expense of accuracy), change it to interpolated, and have a fiddle with the numeric settings, especially tolerance and minimum evalution spacing. You should be able to get some good results out without going the full montecarlo. Also you could try backdrop only, though this is more for outdoor scenes with a sky providing the fill light.

Control: Faster More Accurate
Rays per eval Lower values Higher values
Indirect bounces Lower Higher (this really slows down)
Tolerance Higher Lower
Min Eval Spacing Higher Lower