J wrote in message <35b4f959.3340295@news.povray.org>...
>OK, I know it's been gone over before, but I can't find it anywhere...
>Can anyone help me out in making a windowpane of frosted glass, so it lets
the
>lights outside through, but you can't see through it?


Well, frosted glass in real live gets its effect from either embedded little
shapes (mostly air-bubbles) or from a very uneven surface, often in some
kind of repeating pattern.

Embedding airbubbles one by one would be hard, but you can make a nice
while-loop which differences a lot of spheres out of your windowpane (which
would be a "flat" box). Of course you need a lot of those bubbles and they
need to be very small compared to the size of the pane!

An uneven surface should be possible by heavily disturbing the normal of the
pane. Either with some pattern or with a normal-map (with a map you can even
achive some kind of pattern).

Or combine both...

And don't forget to set the refraction index (ior) to something >1 (1.5 for
glass?)

But be warned: The frosted effect in real live is created by heavily
refracting the light falling through the window. The methods above do it in
the same way - so prepare for some longer render-times (especially if you
add reflection too)...

Hope it helps,
Johannes.

Post a reply to this message