They are interchangeable in terms of meaning, but not in terms of layout and flow. If there is precedent for a given codepoint to have alternate glyphs when used in a LTR versus TTB flow, then that may suffice.
But not entirely. I have seen text that uses vertical-barred glyphs in LTR and horizontal-barred ones in TTB and standalone-section-numbering, but I have also seen pure-LTR text with horizontal-barred ones. I think simply having two glyphs is the simplest. And it's only 20 codepoints. Jameson 2013/7/2 Szelp, A. Sz. <[email protected]> > One never stops learning... > I'd be very interested in the examples, especially in how far they are > non-interchangeable. > > Thanks > > Szelp, André Szabolcs > > +43 (650) 79 22 400 > > > On Tue, Jul 2, 2013 at 1:03 PM, Jameson Quinn <[email protected]>wrote: > >> 2013/7/2, Szelp, A. Sz. <[email protected]>: >> > The question is, whether the two versions (horizontal and vertical) are >> > warranted for or not. >> > With my limited knowledge of the matter, I would believe only one set >> to be >> > encodable, the other being free / stylistic variation. >> >> I have examples of printed pages using both forms on the same page >> non-interchangably, if that helps. >> > >
