Re: tree border
Angus Dorbie (dorbie++at++multipass)
Fri, 21 Nov 1997 14:33:19 -0800
On Nov 19, 6:14pm, Frederic Francis wrote:
> Subject: Re: tree border
>
>
> IMHO, the solution proposed by MultiGen is not the best one. There is a
> general way to preprocess any alphatexture which eliminates completely the
> "alpha halo" or "alpha outline" effect without having to generate custom
> mipmaps.
>
> We have an app that navigates through forests with 3D trees (conical
> trunks + double-sided single polygon branches). Our typical forest
> has a few hundred trees each with a several dozen branches. In this
> situation, the average color approach doesn't cut it.
>
> I am not allowed to give out the algorithm but I felt that if someone
> is writing an app where the visuals could be ruined by "alpha halo"
> they should know that it can be eliminated.
Yep, you basically colour any texel with alpha == 0 with the
rgb of the nearest non zero alpha texel or a weighted average
of the nearest colours.
Cheers,Angus.
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