Core RISC OS free fonts
-----------------------

This is a collection of fonts from the operating system RISC OS,
originally produced by Acorn Computers.

It contains fonts that are metric compatible with the Postscript Level 1
core fonts/PDF core fonts. It also contains several other miscellaneous
fonts.

Please note, I am not a font expert and there may well have been
mistakes made during the conversion process. However I hope they may be
useful for people and could be developed further.

Fonts are (c) RISC OS Developments Ltd and are released under the terms
of the Apache License 2.0. Please see file LICENCE for more details.

Font conversion by Peter Howkins. June 2021.

Font Descriptions
-----------------

Level 1 Core Fonts

- Corpus - Courier
  Medium, Medium Oblique, Bold, Bold Oblique

- Homerton - Helvetica
  Medium, Medium Oblique, Bold, Bold Oblique

- Trinity - Times New Roman
  Medium, Medium Oblique, Bold, Bold Oblique

- Selwyn - Zapf Dingbats

- Sidney - Symbol

Additional Fonts

 - NewHall - New Century Schoolbook
   Medium, Medium Italic, Bold, Bold Italic

 - Sassoon
   Primary, Primary Bold
   - Warning the font current has the wrong encoding due to a segfault
     in acorn2sfd with the Base0 encoding.

 - System - An outline version of RISC OS's bitmap 'System' Font
   Fixed, Medium


Conversion Process
------------------

The fonts are converted using Fontforge's 'acorn2sfd'. They were then
post processed to remove broken winding rules, and broken hinting.
The scripts used to generate these fonts are located in the Tools
directory.

Four oblique fonts (Corpus Medium Oblique, Corpus Bold Oblique, Homerton
Medium Oblique, Homerton Bold Oblique) could not be automatically
converted with acorn2sfd as they are in a different font format that
it did not understand.  The outlines file contains matrix transform values
that describe how the Oblique fonts are generated from the base fonts.  The
generation scripts recreate this transform assuming a skew of 12 degrees.

Sassoon Primary and Sassoon Primary Bold currently have the wrong font
encoding due to a segfault with acorn2sfd when using the Base0 encoding.

Some of the glyphs in Trinity Bold are malformed, causing too much space
above the rendered font, so have been removed from the generated .sfd file.