Re: i18n-ISSUE-401: Clarify initial letter requirements and alignment points

Dave, this is a more general comment about drop caps or similar initial 
letters, not specific to Indic.

There are a variety of styles of drop letters employed in European 
typography, historically speaking, and today I've been thinking through 
a way to address them all within a single architecture. Several of these 
drop cap styles are displayed in Bringhurst's _The Elements of 
Typographic Style_ (p.64 in v2.5 of the book); to these I would add the 
occasional convention of a somewhat smaller drop cap floating in the 
middle of a larger square defined relative to the line height, and the 
use of decorative caps, either square or with their own proportions.

It seems to me that all the cases can be described in terms of a field 
and the relationship of one or more glyphs to that field in terms of 
size and position. I wonder if it would be possible to capture this in 
CSS, such that a default behaviour could be defined based upon line 
distance and font metrics, but also enabling custom overrides, such that 
an author could manipulate the dimensions of the field and also the 
scaling and positioning of the glyph within it?

[This would, obviously, be most relevant in the context of webfonts, 
where the glyphs to be displayed can be properly previewed during 
authoring. I presume it might also be possible to define different 
initial letter overrides to different fonts in a fallback sequence, and 
in the last case to fallback on default behaviour. In general terms, the 
use of webfonts moves web typography closer to that of traditional type 
specification for print, where knowledge of the characteristics and 
behaviour of particular fonts enables more precise control of their use. 
If CSS can provide this level of control, while also supporting sensible 
defaults, this would enable both refined typography for more or less 
static content with predictable display, while ensuring good or better 
handling of arbitrary text in situations where the typographic display 
is not subject to such fine control.]

In the context of Indic scripts, where the overall height of a 
particular graphical cluster cannot be determined from any font metrics, 
due to vertical offsets of mark positioning or consonant stacking, I 
think being able to control the size of drop letters/clusters and their 
field independently would provide authors with necessary control to 
avoid overlaps, clashes, clipping or other tragedies.

JH


-- 

Tiro Typeworks        www.tiro.com
Gulf Islands, BC      tiro@tiro.com

If stung by another man's bee, one must calculate the
extent of the injury, but also, if one swatted it in the
process, subtract the replacement value of the bee.
— Mediaeval Irish legalism

Received on Saturday, 17 January 2015 02:35:12 UTC