Bundled viewer fonts
====================

The viewer serves twelve OpenType files from TeX Gyre 2.004 by B. Jackowski
and J. M. Nowacki: Heros, Termes and Cursor, each in regular, bold, italic and
bold italic. The viewer exposes them through @font-face rules under the
family names Helvetica, Times and Courier.

Font files: https://mirrors.ctan.org/fonts/tex-gyre/opentype/
Complete package: https://mirrors.ctan.org/fonts/tex-gyre/
Project pages, as the family README files give them:
  http://www.gust.org.pl/projects/e-foundry/tex-gyre/heros
  http://www.gust.org.pl/projects/e-foundry/tex-gyre/termes
  http://www.gust.org.pl/projects/e-foundry/tex-gyre/cursor

Each file is byte-identical to the upstream file. faces.json records its
SHA-256, and `npm run fonts:gate` fails if a shipped file differs.


Licence
-------

The fonts are distributed under the GUST Font License (GUST-FONT-LICENSE.txt).
That licence is an instance of the LaTeX Project Public License 1.3c
(lppl.txt). The family README files say that the Work is the set of files
listed in its MANIFEST file. This directory includes the README and MANIFEST
files of the three families.


Change log required by LPPL 1.3c clause 6
-----------------------------------------

LPPL clause 2 says that distribution of only part of the Work is modification
of the Work. This directory has 12 of the files that the three MANIFEST files
list, so it is a Derived Work, although no file is changed. Clause 6 applies,
and this distribution meets it as follows.

  a. No component of the Work is changed, so no component replaces an
     original under a changed identity.
  b. This file is the complete log of changes: files were selected; no file
     was edited, converted or renamed.
  c. The TeX Gyre authors do not support this distribution. Report problems
     to the maintainers of this viewer.
  d. The URLs above give access to the complete, unmodified Work.


Font and file names
-------------------

Clause 1 of the GUST Font License requests, but does not legally require,
that a derived work is distributed only after the font names in MANIFEST
section 1 and the file names in MANIFEST section 2 are changed.

This distribution keeps the names. Each font file is the upstream file
without change, so its internal names identify the font that it contains.
New internal names would need an edit of each file's name table, which is
itself a modification.

Subsetting a font or converting it to WOFF or WOFF2 produces a file that is
different from the original. The LPPL defines a Modification as the
production of a file that contains an original file, or a significant part
of it, translated into another form. Clause 9 says that an alternative
format does not relax the licence. Such a file is therefore a modified
component. Before you ship one, give it new font names and file names as
MANIFEST sections 1 and 2 request, and add an entry to this change log.

Size: the twelve files total 1,459,028 bytes (789,934 bytes with gzip -9).
WOFF2 would total 659,148 bytes, measured with fontTools 4.59.2. A page
downloads only the faces that its text uses.
