OSDev.org

For my OS project, I was originally using bzt's SSFN2 library. The problem is that it proves to be massively unstable, and also takes up a lot of space (for a fallback kernel TTY that I intended to use it for). It has page-faulted several, several times even after I concluded that my memory management functions were not the cause of fault. I also prefer to write things on my own.

Instead, I am writing a new font renderer using PSF-format fonts. It's a nice mix between modularity, standard, and simplicity.

Only issue is that I am not aware if built-in Linux PSF-format fonts are GPL'ed or not. My project is licensed under CC0, and while nobody is going to hunt for my head for using GPL'ed material, my OS is designed to be consistent and clean, and used as a resource for learning.

Is there any source of PSF fonts that are in the public domain?

In the United States, bitmap fonts (such as PSF files) are not copyrightable.

In other countries, you might have to pay more attention to the license included with the PSF files. Your distro's package manager can tell you where to find it. The PSF files included with Linux distros are usually GPL.

If you find a font in some other format with a permissive enough license, you could convert it to PSF. I found someone who already did that with one font. (I haven't tried it myself, so I can't say how good the conversion is.)

Octocontrabass wrote:In the United States, bitmap fonts (such as PSF files) are not copyrightable.

Good to know.

The Tamsyn font has no restrictions on use or redistribution.

It can be found here: http://www.fial.com/~scott/tamsyn-font/

austanss wrote:

Octocontrabass wrote:In the United States, bitmap fonts (such as PSF files) are not copyrightable.

Good to know.

To clarify this..

Fonts in the US follow similar copyright rules to cookbooks: The things they describe are not copyrightable, but the presentation may be. Typefaces - the design of the glyphs in a font - are specifically not copyrightable under 37 C.F.R. § 202.1(e). But, a font file may be subject to copyright if it involves creative representation or artistry: That includes being a "program". This means TrueType/OpenType fonts and even just vector descriptions in general are still considered copyrightable, even if the glyph shapes they are describing are not. Bitmap font files, though, don't meet the same conditions.

Japan is similar, the courts here having decided that typefaces are meant to convey information - not artistic expression. However, many countries do extend copyright protection to typefaces. Germany, the UK, Ireland, Israel...

All that said, there's plenty of typefaces and corresponding fonts available under the SIL Open Font License, which has some unique requirements (eg. you can't sell a SIL licensed font alone, though you can sell it in a bundle, so including a SIL licensed font in a commercial product is totally fine) but is otherwise approved of by all the FOSS orgs.

For my bitmap font needs, I baked a bitmap version of Deja Vu (which has its own license that is basically the same as a BSD license but with some requirements for not distributing modified versions under the names of its originating sources), which then matches up nicely with the original TrueType version I use in userspace.