This is pretty simple and straight forward.I am writing this post because as of today(20/04/2014) I could not find a proper guid to install Sinhala Unicode in Gentoo.
Almost all tools I am going to use, should have been installed in the system. I used wget to get lklug.ttf from sourceforge and shoud be run this command as root(as sudo if you have installed and configured sudo). You can manually download the file and put in /usr/share/fonts directory as well.
wget -P /usr/share/fonts http://sinhala.sourceforge.net/files/lklug.ttf
Then update font cache
Next enable Sinhala locale: using any text editor add following to /etc/locale.gen file
And generate locale using command,
Now you should be able to see Sinhala fonts immediately in your system. You might need to restart applications NOT the system. For me just reloading Firefox tab (Aurora with gentoo branding) was enough for me.
Thats it 🙂 and now, you may be want to visit Sinhala Wikipedia page and testify.