Add a way to display shadow map.
Reverse shadowmap views.
Add wireframe frustrum view.
Fix build
Fix shadowdebug not using right viewfrustrum
Merge branch 'master' into shadowdebug
Tigher fit of shadow map.
Fix GI matrix generation.
Fix disappearing shadows
Use EAC_OFF
Merge remote-tracking branch 'origin/shadowdebug'
Merge branch 'master' of https://github.com/supertuxkart/stk-code