Re: [font-metrics-api] Zooming out on font metrics

Alan Stearns wrote:

> So the capHeight measure for a deadrange, deadfragment and element
> would always be the capHeight measure of the first glyph of the first
> in-flow linebox (with any other qualifications we might need to
> stipulate, particularly for deadranges that might start in the middle
> of a glyph). We should arrive at a consistent definition that gets to
> the actual source of the data, and we can quibble over whether these
> things should be made available in a single interface or several, but
> I definitely think it’s sane and useful to talk about the capHeight of
> an element.

This is *precisely* what I was talking about.

The 'capHeight' of the first glyph in a line is a font metric, it's not
a linebox metric. There may be metrics for the line that boil down to
the max capHeight of all the inline boxes within a given linebox but we
should keep the two separate. While spec'ing things this way may help
your dropcaps example I don't think it's a good thing for a more general
set of use cases.

John Daggett


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