POV-Ray: Newsgroups: povray.beta-test: Output Alpha problem when exporting from blender: Re: Output Alpha problem when exporting from blender

POV-Ray : Newsgroups : povray.beta-test : Output Alpha problem when exporting from blender : Re: Output Alpha problem when exporting from blender		Server Time 6 Jul 2024 06:04:09 EDT (-0400)

From: Thorsten Froehlich
Date: 23 Mar 2010 12:13:26
Message: <4ba8e8a6$1@news.povray.org>

On 23.03.10 17:05, Warp wrote:
>    IIRC, POV-Ray 3.5 mishandled alpha transparency against the background
> in that with antialiased edges and semi-transparent surfaces it blended
> the surface's color with the background color and then saved the resulting
> color with an alpha value. This caused object borders to have a pixel-wide
> halo of the wrong shade, and especially semi-transparent surfaces would have
> the wrong color.
>
>    This was fixed in POV-Ray 3.6, where it's calculated correctly (iow. the
> background color has no effect on the pixel colors when using +UA).
>
>    Last time I checked (it has been some time, though), the same problem had
> resurfaced in POV-Ray 3.7 beta. Someone had undone the fix in POV-Ray 3.6.
>
>    Has this been corrected already?

The fix was that alpha is treated differently depending on the version 
directive as the 3.6 change was unpopular...

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