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 This is a utility for generating signed distance fields from vector shapes and font glyphs,
 which serve as a texture representation that can be used in real-time graphics to efficiently reproduce said shapes.
 Although it can also be used to generate conventional signed distance fields best known from
-[this Valve paper](http://www.valvesoftware.com/publications/2007/SIGGRAPH2007_AlphaTestedMagnification.pdf)
+[this Valve paper](https://steamcdn-a.akamaihd.net/apps/valve/2007/SIGGRAPH2007_AlphaTestedMagnification.pdf)
 and pseudo-distance fields, its primary purpose is to generate multi-channel distance fields,
 using a method I have developed. Unlike monochrome distance fields, they have the ability
 to reproduce sharp corners almost perfectly by utilizing all three color channels.