Vertical text

[xfq]

When N’Ko and Adlam text is in vertical writing mode (e.g., in the spine of a book, or embedded in vertical Chinese/Japanese/Korean/Mongolian text), how is it rotated? Is it top-down or bottom-top?

[andjc]

@xfq your question seems to be two separate questions:

1. re spine of books. for me vertical writing mode implies grapheme clusters stacked vertically top to bottom, which I would consider rare. More common would be text rotated 90 deg. I would assume anticlockwise. But others may have more knowledge of this.

2. Re Adlam and N'ko orientation IN CJKM text, this is more of a question of Chinese and Japanese publishers' preferences and practices, and better asked in the appropriate repos. I assume Chinese and Japanese publishers would use the same approach as they would for Arabic, Hebrew, Old Turkic, etc.

[r12a]

Book spines in Latin text can run top to bottom or bottom to top, often depending on the country. I assume that for book spines that are not mixed with CJKM text the text is sideways throughout. The writing-modes:sideways-xx property would be appropriate to rotate text in this way.

When N'Ko or Adlam are added to vertical CJK text i would expect that by default they would run sideways up the line from bottom to top, as do Arabic and Hebrew, in web pages. In this diagram the N'Ko letters join at the baseline.

[DD-fwd]

I have not seen vertical writing mode in NKo literatures yet, others may have. I do see it being explored by artists/calligraphers; I understand @r12a's comment about the default behavior. If vertical writing mode is used, it will make the reading and handwriting (digital and handwriting conform) easier if it uses unconnected letters in a top to bottom orientation. Of course, I will be interested in hearing more on this.