How to do light?

Can someone tell me how to do a box or a cylinder that glow as a bulb?

Can somebody also tell me how it can start to glow in the sunlight? - or to touch it to lighten up or close down?

To make a prim glow, change ts material to light.

If you want a cone or orb of light to surround the bulb, use a phantom, partly transparent light prim.

You can do this with scripts, of course, if you want to program on-off controls.

I've heard that light can cause lag, but I've never noticed that myself.

I've got a couple of simple example scripts--IM me in world. (But not during Captions!)

Objects that have been set PRIM_MATERIAL_LIGHT cause lag for users who have enabled the 'local lightning' rendering feature. This is particularly bad for large prims, or when a large number of objects have been set to be lights. The client will essentialy trace a path from any light object to all surrounding prims within a radius that is apparently determined by the physical size of the light source. A 10m^3 cube set light, for example, will cast light over much of the sim, potentially over thousands upon thousands of prims. This is extra calcuation for the client and causes serious lag.

Ideally, in any build, a minimal number of prims set light should be used, and these should be scripted to 'turn off' the light during the daylight hours to minimize lag on clients with local lighting enabled.

”should be scripted to 'turn off' the light during the daylight”

Please where can I get that script then to be a good citizen.

You needn't look any further than the scripting library forum here on the secondlife forums!

Here:
Light script.

I should note, however, that not all your neighbours may find a 60-second timer much more comforting than a light that stayed on.

Heh, that's a good point. I should post an adapted version of that script based on successive llSleep() calls...

Speaking of lag, Eggy Lippmann talked that there was a problem in a way to turn a light on and off. Plz note this as well.