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LEGACY FONTS: CONVERSION FROM PSF TO BDF
========================================

The traditional font collection for Linux console was a big mess.
There were many different fonts and nobody in the world knew the exact
purpose of all of them.  During the years new fonts were added, but
old were almost newer removed.

Some of the fonts shared common typeface, i.e. they were differently
encoded but the common glyphs were equal.  In total, however, there
were too many different typefaces that generally differ one from
another only a little.

In order to reduce the total number of fonts, they were converted to
BDF format.  During the conversion of the fonts, only one BDF font was
generated for a group of fonts that share common typeface.  Console
fonts that didn't have embedded Unicode table were simply ignored.
The fonts LatArCyrHeb* were also ignored - partially due to technical
reasons and partially because the other BDF fonts are better source for
making Unicode console fonts.

The resulting BDF fonts are named after the scheme legacyNNp.bdf,
where NN is 8, 10, 12, 14, 16 or 19 (the number of scan lines of the
font, i.e. the font matrix is 8xNN) and p is a, b, c, d, e,... and
serves to ensure the uniqueness of the file names.  The table at the
end of this text, documents the correspondence between file names of
the resulting BDF fonts and the names of the PSF fonts that were used
to produce them.  We see that some of the resulting BDF fonts were
produced by only one source PSF font (for example only iso06.f08.psf
was used to produce legacy8d.bdf) while for others it was possible to
incorporate the glyphs from more than one PSF font (for example six
PSF fonts were used to produce legacy16e.bdf).


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LEGACY FONTS: BACK CONVERSION -  FROM BDF TO PSF
================================================

Only one PSF font per combination of codeset-size is generated from
the legacy fonts and is named after the scheme CODESET-vgaSIZE.psf.
For example Greek-vga14.psf is the legacy font for Greek code set and
size 14.  The list of BDF fonts that is used to produce
Greek-vga14.psf was determined as follows.

First, see which one of the legacy BDF fonts can provide as many
glyphs for Greek-vga14.psf as possible.  This was legacy14g.bdf
(produced from iso07.f14.psf).  Then see which one of the other legacy
BDF fonts provides as much glyphs for Greek-vga14.psf that legacy14g
does not provide.  And so on.  The resulting lists are represented as
Codeset-legacySIZE-BDFS targets in the Makefile.  It is perfectly OK
to handtune them.  For example if one decides that the look of
legacy16i.bdf is superior it is OK to list legacy16i.bdf as primary
font for Lat15-vga16.psf even though legacy16c.bdf provides more
glyphs.

There is one exception to the previous paragraph: the wonderful font
UNI_VGA of Dmitry Bolkhovityanov was always used as a primary font for
VGA16 fontface.

====================================
THE SOURCES OF THE FONTS legacy*.bdf
====================================

legacy8a.bdf: cp857-8x8.psf iso01.f08.psf iso05.f08.psf iso07.f08.psf iso09.f08.psf
legacy8b.bdf: Cyr_a8x8.psf koi8u_8x8.psf ruscii_8x8.psf
legacy8c.bdf: iso02.f08.psf iso03.f08.psf iso04.f08.psf iso10.f08.psf
legacy8d.bdf: iso06.f08.psf
legacy8e.bdf: iso08.f08.psf
legacy8f.bdf: lat0-08.psf lat9u-08.psf
legacy8g.bdf: lat1-08.psf lat1u-08.psf lat9v-08.psf lat9w-08.psf
legacy8i.bdf: lat4-08.psf lat4a-08.psf lat4u-08.psf
legacy10a.bdf: lat4-10.psf lat4a-10.psf lat4u-10.psf
legacy10b.bdf: lat0-10.psf lat9u-10.psf
legacy10c.bdf: lat1-10.psf lat1u-10.psf lat9v-10.psf lat9w-10.psf
legacy10d.bdf: lat2u-10.psf
legacy12a.bdf: lat0-12.psf lat9u-12.psf
legacy12b.bdf: lat1-12.psf lat1u-12.psf lat9v-12.psf lat9w-12.psf
legacy12c.bdf: lat2u-12.psf
legacy12d.bdf: lat4-12.psf lat4a-12.psf lat4u-12.psf
legacy14a.bdf: cp857-8x14.psf iso01.f14.psf iso05.f14.psf iso09.f14.psf
legacy14b.bdf: Cyr_a8x14.psf
legacy14c.bdf: koi8u_8x14.psf
legacy14d.bdf: ruscii_8x14.psf
legacy14e.bdf: iso02.f14.psf iso03.f14.psf iso04.f14.psf iso10.f14.psf
legacy14f.bdf: iso06.f14.psf
legacy14g.bdf: iso07.f14.psf
legacy14h.bdf: iso08.f14.psf
legacy14i.bdf: lat0-14.psf lat9u-14.psf
legacy14j.bdf: lat1-14.psf lat1u-14.psf lat9v-14.psf lat9w-14.psf
legacy14k.bdf: lat2u-14.psf
legacy14l.bdf: lat4-14.psf lat4a-14.psf lat4u-14.psf
legacy16a.bdf: cp857-8x16.psf iso01.f16.psf iso05.f16.psf iso07.f16.psf iso09.f16.psf
legacy16b.bdf: Cyr_a8x16.psf koi8u_8x16.psf ruscii_8x16.psf
legacy16c.bdf: default8x16.psf lat0-sun16.psf lat2-sun16.psf
legacy16d.bdf: viscii10-8x16.psf
legacy16e.bdf: iso02.f16.psf iso02g.psf iso03.f16.psf iso03g.psf iso04.f16.psf iso10.f16.psf lat2u-16.psf
legacy16f.bdf: iso06.f16.psf
legacy16g.bdf: iso08.f16.psf
legacy16h.bdf: iso14.f16.psf
legacy16i.bdf: lat0-16.psf lat9u-16.psf
legacy16j.bdf: lat1-16.psf lat1u-16.psf
legacy16k.bdf: lat4-16.psf lat4a-16.psf lat4u-16.psf
legacy16l.bdf: lat9v-16.psf lat9w-16.psf
legacy16m.bdf: lat4-16+.psf lat4a-16+.psf lat4u-16+.psf
legacy19a.bdf: lat4-19.psf lat4a-19.psf lat4u-19.psf
Goha12.bdf: Goha-12.psf
Goha14.bdf: Goha-14.psf
Goha16.bdf: Goha-16.psf
GohaClasic12.bdf: GohaClasic-12.psf
GohaClasic14.bdf: GohaClasic-14.psf
GohaClasic16.bdf: GohaClasic-16.psf

