asked around on there irc, but the main coder is not available for some time (studying) so all information i got so far is this :
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<Chilli_> question : does anyone know how to fix the q3 shadow bug (cg_shadows 2 shines through walls) i allready asked in german #xreal, they said Tr3b/trebor is the man, but he has no time (studying)
<Wudan> it's a stencil issue
<Wudan> you need to make the 'far' caps stop at the wall, takes work
<Wudan> no idea how to do it cleanly
<Chilli_> i try an email to
quake3@icculus.org perhaps they have a look thx for answer
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so i email
quake3@icculus.org, perhaps they take an aproach on it