"Dave VanHorn" <mic### [at] gmailcom> wrote in message 
news:web.4907254237e3ca30a08ed15e0@news.povray.org...
> "Bob Hughes" <omniverse charter net> wrote:
>
>> Your area_light isn't what I've ever used or recall seeing used, having 
>> no
>> perpendicular axis to make the grid of lights. And yet that doesn't seem 
>> to
>> be the actual problem you are getting there, if mine rendered the same 
>> here.
>
> The docs say you can make it a linear light by doing X1 in one axis.

You're right. My mistake. First sentence from the docs says so, and now I 
realize I have done that before. I was trying to recall the docs and was 
only thinking of the grid made from two axes. Awful memory. ;^)
>
>> Also not knowing your Chalice object means it is possible a surface is
>> obscuring the light. There might be a clue by how your fire object has a
>> bottom slightly above the light_source, perhaps meaning your Chalice has 
>> a
>> surface at the same place? So remember area_light remains a point-like
>> source based on its location and not the grid being created.
>
> It should be, but not completely.  That's what I intend.
> I thought I'd outsmart it and use a "looks like" to find out where the 
> lights
> are, but that just gives one sphere no matter how many lights I specify.

Okay. I neglected to mention keyword 'jitter' before since I thought you 
must know of it and were trying for banded shadows from the flames. I'm 
guessing now you might have been wanting to use that afterall to smooth the 
shadows.

I rendered your new example (without the line wrap, heh-heh!) and I see you 
lowered the light brightness drastically. It seems to do as expected. I 
changed the light color to rgb <0.75,0.5,0.5> to give it color something 
like the flame itself and the brightness makes for better shadowing so I 
could see what was going on. I also put the whole thing into a 10 unit 
radius room (white sphere) with a floor (white plane at y=0). That 
fade_distance and fade_power both being 2 really dims quickly.

Getting back to the idea of a linear light... if I were you I'd put some 
width on the flame light. That could be part of the trouble with the 
shadows. When I used:

 area_light <0.5,0,0>,<0,1.5,0>,5,15 jitter

it really helps smear out shadows of objects placed around the flame. In 
fact, if you were to animate it I would try varying the area grid a little 
to move the shadows by putting small random numbers added/subtracted to the 
vectors.

Something else I'm not keeping familiar with these days is 'orient' which 
you originally had used in area_light. I found it to make shadows grainy so 
I upped the grid numbers (5,15) to make that better.

Hope you get this looking how you need it.

Bob H.

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