I was looking for best quality bitmap font software for use with small fonts (size 12-14). After a lot of testing i've got best results by far with FontBuilder (https://github.com/andryblack/fontbuilder). Unfortunetly last compiled version doesn't support FNT format. I've tried to download the sources and compile it with Qt. After fighting with this sh..t half day i've failed So i've written simple converter from most similar supported format - NGA.
So how can we get best quailty bitmap font:
1. Get Font Builder (https://github.com/andryblack/fontbuilder/downloads).
2. Prepare bitmap font and export it in NGA format.
3. Download NGAtoFNT (http://www.taern.com/nga2fnt/NGAtoFNT.rar)
4. Open NGAtoFNT
5. Select font.xml with NGA format.
6. click convert
7. click save to save output to file.
Hope it will help somebody