Patrick Elliott <sel### [at] rraznet> wrote:
> In article <44a85af5$1@news.povray.org>, zeg### [at] povplacecom
> says...
> > "Patrick Elliott" <sel### [at] rraznet> wrote in message news:MPG.1f1092509c
> 9cfad9989f32@news.povray.org...
> > > Yeah, I know you can use Radiosity. I was thinking in terms of what
> > > might work "without" that.
> >
> > how would you do what you describe without using a very similar technique
>  POV-Ray's radiosity uses?
> >
> No idea. Its not like I can code the idea. lol
>
> Frankly, I kind of wanted either a) that won't work at all, or b) it is
> an interesting idea. A long laundry list about why I could solve the
> same problems with a mess of other features was "not" what I was after.
> As I said, I rethought it several times. Its possible that it isn't
> possible and a totally pointless idea, if I knew enough to realize it.
> Telling me I can "sort of" get the same result I envisioned with other
> stuff or a bit like saying, "You can sort of make a flying car of you
> strap wings and a jet engine on a VW Bug.", without bothering to say why
> using a VW Bug is a better alternative that just building a flying car.
> One good reason might be, "It won't work anyway.", but that's not what I
> ended up with. ;)
>
> --
> void main () {

>     call functional_code()
>   else
>     call crash_windows();
> }

The responses you got are what they are because that's simply what's
possible, and what's effective. You can't put a light-source in the
sky_sphere because it isn't an object, but an abstraction. Like background,
it's not really there, but is something added if the ray doesn't hit an
object. Light sources need _some_ positional parameter, and a sky_sphere,
despite accepting the same pigment_map function that other objects do,
doesn't provide that.

You were told that the best way to get the low-key lighting from the sky was
to use radiosity, but you rejected that. It's resource-intensive, fair
enough. Would have been good if you had said that, instead of just no, I
don't want it. You're asking people to give you advice for free, if you're
going to reject it openly, at least tell us why.

Then it was suggested that you use a low-intensity shadowless light source
instead, but you rejected that idea too, saying you were looking for
something else, when what you said was just what was suggested. That low
intensity beyond the cut-off that you were asking for, that's what a
shadowless light source is. If you're still dead-set on using sky_sphere to
simulate the appearance of the sun, give it an x-gradient with yellow (or
white if you prefer) from say 0.9 to 1.0, make the rest of it blue, then
rotate it -45*x. Play with the starting point of the white til you get the
size you want. I'm assuming you're looking in the z direction, btw. If not,
adjust the rotation accordingly.

Please know what you're asking for. You asked for a flying car, and you were
told *both* the VW bug and build it answer, but you ignored them both.

Andrea

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