light and avi position

consider two objects, a sphere a meter or two away from a square which has a flat side facing the sphere. if the square has been scripted to have full light on, and large radius and no dropoff, and you turn midnight on in your client, the square sheds a nice light on the sphere with shadowing etc.

now step your avi back from these prims ten and twenty meters. the light from the square is no longer being cast on the sphere!

i.e. the effect of a light cast on an object is relative to the viewer's avi. this is an exceedingly major pain to me as it makes the stage lights (for sl ballet) i am building utterly useless.

wtf?

There is a limit on the number of concurrent light sources. OpenGL supports eight light sources of which six are available to the client.

The Client always renders the six closest light sources. And there is absolutely nothing you can do about that.

well, not entirely true, I believe that it is possible to have more rendered lights through use of a custom built client (try libsl), but yes, for all intents and purposes, having more than 6 light sources in one area is pointless.


Perhaps with the upcoming windlight release this will change.

One thing you could try (which we are doing for ACT UP theater's upcoming show), is to have all the avi's on stage have their own light attachments (like the Sweetlight attachment). They seem to be not to difficult to make, and they ensure even lighting on each avi, provided that there are not too many additional external light sources around.

Actually, OpenGL only mandates 8 hardware lights on compliant graphics cards, so no custom client can guarantee to have more than that available on any given piece of hardware.

SL Virtualizes the lights rather crudely - it uses the hardware lighting for the sun & moon, and the 6 nearest local lights. Everything else is rendered in software.