The question
of a character set for Indian languages/scripts arises for text preparation
and display as well as linguistic processing. If one were to look at Tamil
in totality from ancient Sangam period to modern times, a number of special
symbols and notations are seen in the texts and manuscripts. Handling Tamil
text for Display and printing may not impose requirements that are difficult
to meet.. However linguistic processing will suffer if one does not identify
the symbols and shapes that will have to be displayed.
During the years of
the development of the Tamil script (typically from 200BC to 1800 AD),
changes were prominent as slowly, the mixture of Grantha and Tamil letters
in stone inscriptions yielded to the Tamil letters. Interestingly, separate
but arbitrary set of symbols had also been used to refer to fractions,
measure of land and such and it appears that more than 500 different symbols
will be required in a font if text in stone inscriptions should also be
handled.
The experience
at IIT Madras in dealing with the Tamil scripts from ancient rock inscriptions,
palm leaf manuscripts and printed texts during the past two hundred years
has led to recommend a useful set of glyphs for dealing with Tamil on a
computer. As of today, none of the fonts in use (including the most popular
fonts seen on the web) cater to this set. There is no need to honour this
set in full for any given application and perhaps this explains why designers
of fonts for Tamil have used only a limited set.
The Tamil Script is one of the simpler scripts based on twelve
vowels, eighteen consonants and a few special symbols. The ten numerals
have specific shapes in this script. There are six consonants from
Sanskrit which have specific representation in the script in use today.
These are usually referred to as the Grantha letters. The Grantha script
has been in use in South India as the basic writing system for Sanskrit.
The Tamil script has undergone significant changes over the centuries and
the script in use today is a simplified version, specifically aimed at
bringing in some uniformity in medial vowel representations. Tamil text
printed during the nineteenth century was typeset in the older version
of the modern day script.
Fonts designed for Tamil should try and provide for glyphs to
accommodate the earlier representations of medial vowels and some of the
special symbols.