A face's glyph height (the height of the glyph image) isn't necessarily
the inter-line spacing: f.Ascent + f.Descent isn't always f.Height.
Similarly, a face's glyph image's left side isn't always dot.X.
Change-Id: I86594c52b8d31bf652ac34a695e9270ac635a5bc
Reviewed-on: https://go-review.googlesource.com/24481
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The key feature is that its data is entirely self-contained and does not
require loading from separate files.
Change-Id: I4ef72b52cde93597be89dcfd55659f418c6cab23
Reviewed-on: https://go-review.googlesource.com/14486
Reviewed-by: Rob Pike <r@golang.org>