Should mention position of underline for vertical writing mode

[upsuper]

JLReq mentions that in vertical writing mode, sidelines (which is handled as underline in CSS) are on the right side of characters. I heard that in Chinese, we put underline on the left side, but that doesn't seem to be mentioned anywhere in CLReq. I guess this is something should be added.

cc @kojiishi

[ethantw]

專名號為U+FF3F FULLWIDTH LOW LINE [＿]，標示於專有名詞——如人名、地名等——底端之符號。

Actually, 底端 (foot side) does not mean the visual bottom side of text but the side of text that is closer to the foot end of the layout. Hence it could mean both bottom side of text in horizontal writing mode and left side of text in vertical writing mode. Similar terms and definitions are listed below:

• 頂端 (head side) the side of text that is closer to the head of the layout
• 底端 (foot side) explained as above
• 始端 (starting point) the side of a character that is in between the character and its previous one
• 末端 (end point) the side of a character that is s in between the character and its following one

The corresponding English translation is inaccurate though (sorry 😝). Will have to correct it later and add the explanation to glossary too (and of course the figures)…

U+FF3F FULLWIDTH LOW LINE [＿] is positioned underneath proper nouns such as a person's name, the name of a place, etc.

[c933103]

Does that mean, when writing chinese text within article that is predominately written with traditional mongolian script and follow that script's direction, i.e. vertical, left to right, the underline for chinese characters should go right?

[ethantw]

@c933103:

The requirement does not automatically apply to layouts in other languages. CLReq is not the authority to these cases. It can only provide some reference, not the golden rules.

[c933103]

I mean, when you write a long paragraph of text in vertical-lr language, and that long vertical-lr paragraph embedded several lines Chinese text into the paragraph, those Chinese text would become vertical-lr, and the footer of the layout would become right hand side, and from what you have wrote, those low lines should go right in this case.

2016年11月29日 20:16 於 "Chen Yijun" notifications@github.com 寫道：

@c933103 https://github.com/c933103:

The requirement does not automatically apply to layouts in other languages. CLReq is not the authority to these cases. It can only provide some reference, not the golden rules.

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/w3c/clreq/issues/113#issuecomment-263555372, or mute the thread https://github.com/notifications/unsubscribe-auth/ABdGLcN7SYYxahTsxAJ7DXblUDsKYJB-ks5rDBeHgaJpZM4K00t0 .

[kojiishi]

Embedded case should be handled separately, since it occurs to all languages.

I think we should understand requirements for each language first, then we can discuss embedding case with the list of requirements. I hope that can make our discussion easier.

[xfq]

I think it's already mentioned in https://w3c.github.io/clreq/#glyphs_sizes_and_positions_in_character_faces_of_punctuation_marks