clipka wrote:
> Some_Yahoo <no### [at] waycom> wrote:
>> ok I have this hare-brained scheme to make a lightbulb that is etched
>> or "reliefed" with a height map of the Earth.  After 2 days of
>> experimentation, I am at wit's end.
>>
>> The lightbulb should be lit, and used to cast a little radiosity light,
>> but I still want to see the relief of the Earth.
>>
>> I have tried using bump-maps with variations of bright colors (rgb .75 to
>> rgb 3) and high ambient (.75 to 3) and I either get what looks like a dull
>> white avocado or it washes out all white.
> 
> Heh - that's quite a problem indeed: Have you ever stared at an etched light
> bulb in real life? And seen anything of the etching? With the bulb *not* being
> a genuine dull white avocado? :P
> 
> 
> Maybe the best bet would be to make the bulb basically two-colored, using an
> ambient < 1.0 for the "continents", and some whopping >> 1.0 for the "oceans";
> output to HDR format (or, alternatively, to two standard images, one with
> standard brightness and one "tuned down"); and post-process the shot(s) to have
> the overexposed parts "bleed" somewhat into the remaining image.
> 
> 
> (BTW, for your purposes it doesn't really matter whether you crank up the
> pigment or the ambient - both have the same effect on the "light output".
> Except that changes to the pigment also affect the "diffuse" component, and
> possibly highlights and reflections in case you'd happen to be using metallic,
> while changes to the ambient obviously affects the "ambient" component only.)
> 
> 
> 
> 
I went with a felt-marker version.   not totally happy with it but oh well.

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