In article <41db47bc$1@news.povray.org>,
 "Neil Kolban" <kol### [at] kolbancom> wrote:

> If a star is a single point (pixel) in space surrounded by blackness, then
> if we antialias, we will average the single white point by many more black
> points reducing the overall value (brightness) of the white point.

That's essentially the problem. Those textures rely on aliasing to 
create the stars...each pixel is a point sample of a mostly black 
pigment. Occasionally one hits a light area, producing a star. 
Antialiasing just renders the image more correctly, showing that there 
really aren't any stars. It gets worse when you clip colors before 
averaging, since even increasing the brightness won't increase the 
effect on a pixel. (However, not clipping produces jagged edges on very 
bright objects. A real solution will be more complex...)

Simply brightening the stars is unlikely to give good results, it will 
probably just reveal the pattern. Pretty much the only way I know of to 
get decent stars with AA is to use a big shell of many randomly placed 
spheres sized to cover approximately one pixel.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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