Hi.

This problem may have been addressed before...

Anyway, I have discovered a quirky thing I haven't noticed before about
area lights in POV.

It seems when using liht fading, the brightest spot, from where the
attenuation starts is the center of the area_light, i.e. the
illumination is not distributed evenly across the surface of the
area_light source.

This is especially anoying when using higly elongated light sources like
neon tubes with light fading - there is a bright spot of liht at the
nearby wall around the center of the tube, which does not look very
realistic.

I have included an example scene which demonstrates this well (uncomment
the media if U got the time):

/BEGIN SCENE/

camera {location <7,0,-10> look_at <0,0,0>}

light_source {<0,0,0> rgb <1,1,1>
             area_light y*5, x, 5, 2 adaptive 1 jitter
             fade_distance 2 fade_power 2}
             
//media {scattering {1 rgb .1}}
             
plane {z, 1 pigment {rgb .8} finish {ambient .2 diffuse .6} hollow}

polygon {4, <-.5, -2.5, 0>, <.5, -2.5, 0>, <.5, 2.5, 0>, <-.5, 2.5, 0>
         pigment {rgb 1} finish {ambient 1 diffuse 0} no_shadow}

/END SCENE/

Is this inherent in the way POV simulates area lights?
Is there a workaround for this problem?


Thanks.

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