Yeah, I know. Screenshots of a console mode program. It doesn't really work, does it? This page, rather than screenshots of FEIDIAN itself (which would be pretty darn boring) will show screenshots of some of the stuff you can actually DO with FEIDIAN, which might encourage you to give it a try.
First off, lets take a look at one of my all time favorite games, Lufia & the Fortress of Doom. The first step to getting anything at all done with FEIDIAN is finding the font. For this I use Neill Corlett's tile viewer, Nana, set to 8px wide 1bpp mode. Scroll down for a while and eventually you'll see this.
Obviously the font is just a standard 8x16 tile format starting at 0x54650. If you scroll down more, you'll see there's 96 chars. so we want to rip the font by typing:
feidian -r 8,16,16,6,0x54650 lufia.smc lufia
This will produce a file called lufia_8x16.bmp. For this example, I decided to replace it with a font taken from the old VFONT.COM program for setting your DOS console VGA font. I can't remember which of the fonts it is at the moment, but you can see it here. So now, we want to insert it back into Lufia & the Fortress of Doom. Simply type:
feidian -i 8,16,16,6,0x54650 untitled.bmp lufia.smc
An example of how the game now looks is below.
So you can change fonts. Lah-dee-dah. That's probably not useful to anyone who's doing more than a face-lift hack. But with the BDF (and possibly .FON) export I'm working on for the next release, it would make it very easy to turn your favorite game fonts into Windows/Linux system fonts. If you want to get clever with your custom tile formats, you could also transform 2-bitplane game fonts to 1-bitplane ones just by omitting a byte, as I've done here with Chrono Trigger.
There's a lot of possibilities, pretty near the only things FEIDIAN can't handle with 1bpp fonts is compression (which varies game to game so no tool will ever do it) and fonts involving a variable height table, like Fuurai no Shiren on SNES (the only game I have EVER seen use it).
As I've said before though, every tool and its brother is already made to handle SNES. Sony PSX, Sega Saturn, Dreamcast, and PC is the next frontier, and with fonts that aren't based on solid byte widths, a lot of tools are sorely under-equipped to handle them. Take for example, Langrisser IV on the Saturn. Let's open up its SYSTEM.DAT file in Nana.
You can play with it all you like, but as of the moment, that's probably the best focus you will get. The font is a 12x12. We can see it in 24w mode because 12*2=24. Hence why it's busted in half. The font starts at 0x0 in the file. So lets try this command:
feidian -r 12,12,16,124,0x0 system.dat lang4fon
This will produce lang4fon_12x12.bmp. A little bit easier to read, yes? So let's pretend you've made a table for this font, but now you're stuck, because if you try to hack the game, you'll have giant, blocky, 12x12 English letters that will make everyone go into seizures as they remember reading for 40 hours. If you're not one of the few gods of the SH2 out there, a cheap dual-tile hack is probably your only option. FEIDIAN can help with this.
After you've had your script inserter make a histogram of all two-letter combos in the game, take that list and give it to FEIDIAN, along with a half-width (in this case, 6x12) font. FEIDIAN will produce a new 12x12 font for you to insert into the game. Then have your script inserter point each two letter combo to the corresponding hex byte replaced.
It's a nifty and cheap way to do something like this:
There's also the super nifty font exporting feature. You can use it to turn game fonts into Windows fonts (compatable with Windows 3.11 and higher) or BDF fonts (for X-Windows). Here's a picture of the Windows Font viewer showing off a font exported by FEIDIAN:
You could also use this feature to design fonts of your own in Paint or Photoshop, then export them to a Windows font form. Fonts produced by FEIDIAN (or through mkwinfon, in the case of .FON) are useable in all Windows applications that allow .FON format fonts. One of the only ones that don't is Microsoft Word, which only allows TTF vector fonts (for obvious reasons, if you know a bit about typography).
BUT THOU MUST!
FEIDIAN is build on great justice.