cmake build: GiGi not found

[cazfi]

I quickly tested cmake build as it's now the officially supported build method. This is not very high priority for me as scons build works.

When GG is installed under /usr (not /usr/local), cmake for FreeOrion errors out like this:

-- Configuring freeorion
-- checking for module 'GiGi'
-- found GiGi, version 0.6.0
CMake Error at client/human/CMakeLists.txt:20 (message):
GiGi library not found.

These lines from CMakeCache.txt seem like most relevant:

//Path to a library.
GIGI_GIGIOGRE_LIBRARY:FILEPATH=/usr/lib/libGiGiOgre.so

//Path to a library.
GIGI_GIGISDL_LIBRARY:FILEPATH=/usr/lib/libGiGiSDL.so

//Path to a library.
GIGI_GIGI_LIBRARY:FILEPATH=/usr/lib/libGiGi.so

//Path to a file.
GIGI_INCLUDE_DIR:PATH=GIGI_INCLUDE_DIR-NOTFOUND

When GG is installed under /home/cazfi/freeorion/cmakegg, simple cmake fails as expected:

-- Configuring freeorion
-- checking for module 'GiGi'
-- package 'GiGi' not found
CMake Error at client/human/CMakeLists.txt:20 (message):
GiGi library not found.

When GG is installed under /home/cazfi/freeorion/cmakegg and PKG_CONFIG_PATH is set correctly so that pkg-config finds GiGi.pc ("PKG_CONFIG_PATH=/home/cazfi/freeorion/cmakegg/lib/pkgconfig cmake .") cmake command success. But make after that fails. First one of the many errors:

In file included from /home/cazfi/freeorion/TRUNK/FreeOrion/util/Order.h:6,
from /home/cazfi/freeorion/TRUNK/FreeOrion/util/Order.cpp:1:
/home/cazfi/freeorion/TRUNK/FreeOrion/util/../universe/Enums.h:5:21: error: GG/Enum.h: No such file or directory

/home/cazfi/freeorion/cmakegg/lib/pkgconfig/GiGi.pc has correct include directory set:

prefix=/home/cazfi/freeorion/cmakegg
libdir=${prefix}/lib
includedir=${prefix}/include

and /home/cazfi/freeorion/cmakegg/include/GG/Enum.h exist