Some information from readme:
This patch enables partial unicode (unicode strings in UTF8 encoding) support in openttd. Now there are supported unicode chars from 0x000 to 0x7FF, so it is enough to support russian, greek and all central european languages, which have different charset. Ascii codes from basic ascii table (0x00 to 0x7F) and openttd special codes from 0x80 to 0xBF) are mapped to original openttd charset. UTF8 encoded strings from 0x080 to 0x7FF are mapped to extended charset (unicode space).
So, I tested it with russian fonts, because I had no other fonts
![Happy :))](./images/smilies/happy.gif)
These fonts are loaded in this test binary to basic cyrillic alphabet positions in unicode table (0x410-0x44F).
This patch reserves 0x1680 (5760) sprite space, so maybe there is too small space for load own newgrf sprites (I didn't raised NUM_SPRITES).
This patch is not tested very well, I used only few strings to test basic funcionality of patch (I don't know russian
![Smile :)](./images/smilies/icon_smile.gif)
So, I need testing this, next more translated strings in unicode charset with utf8 encoding, and another .grf fonts (especially for central european languages - latin2 charset).
See the files and screenshot to more information.
I hope, this patch will be usefull for people who don't use Latin1 charset and after bugfixing will be in one of next openttd releases.
gpsoft.