Re: Main character animations.

[Steve Baker <sjbaker1@airmail.net>]

Gregor Mueckl wrote:

> > You'll want to render at much higher resolution than you need so you can
> > get them antialiased - also render against a 'blue screen' background so
> > you can delete the background and have transparency in the right places.
> >
> 
> Antialising and blue-screen backgrounds don't mix very good, mainly
> because the pixel at the model's edges will be mixed with the
> background. So if you enable antialiasing on such a scene you will have
> a fixed-colored border around your model which is hard to get rid of.

That's why you render at higher resolution - THEN extract the blue
screen - so you now have an alpha (transparency) 'channel' in your
image. THEN downsize the image to the scale you need to get the
antialiasing effect.

Doing that will leave you with no fuzzy blue halo's whatsoever.
Don't do it in the reverse order though (downsize and THEN extract
the blue) or you will indeed get the effect you describe.

Of course if your renderer can directly produce the alpha channel
then by all means use that instead of a blue screen. (And of course
when I talk about "Blue screen" you'll understand that it could
be a green screen - or some yet less likely colour such as magenta).
 
----------------------------- Steve Baker -------------------------------
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