Best line length

[xfq]

In jlreq:

The best line length (number of characters per line) is around 52 characters, maximum, in vertical writing mode, and 40 characters, maximum, in horizontal writing mode. If the trim size would take lines beyond the recommended length, consider using a multi-column format and making the line length shorter.

For Chinese, is there a similar requirement?

See also https://www.zhihu.com/question/19621078

[ryukeikun]

This is not a "requirement" topic, but as per discussion during meeting, we can add some recommend values for line length like this, as a note that could be added after §2.2.5.3

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NOTE

基于下述理由，行长必须为文字尺寸的整数倍：

1. 中文排版的基本原则是，除段落最后一行以外，每行行尾应对齐
2. 中文排版所用的文字（包括汉字、标点），其字框的设计原则是正方形
3. 中文排版的排字原则是，各种文字应为密排

作为总体原则，行长应依照不同字体、版式、开本以及媒介、根据实际情况设置。一般来说，报纸期刊的行长相对较短，而书籍的行长较长，但作为参考值，大多数书籍的正文行长一般设在 17 到 40 字范围区间。为避免阅读时频繁换行、串行等情况，正文行长最小不宜少于 10 字、而横排最大行长不宜长于 48 字、竖排不宜长于 55 字。

[xfq]

我有几个问题：

as a note that could be added after §2.2.5.3

我们好像没有这一节？

中文排版的排字原则是，各种文字应为密排

这里的“各种文字”指的是什么文字？

作为总体原则，行长应依照不同字体、版式、开本以及媒介、根据实际情况设置。

clreq全文没有提到“开本”，可能需要在术语表或者正文解释一下这个术语。

[ryukeikun]

我们好像没有这一节？

笔误。应该是 §2.3.5.3

这里的“各种文字”指的是什么文字？

其实就是 2. 提到的「中文排版所用的文字（包括汉字、标点）」，如果此处会引起误解，干脆就直接写作「文字」

clreq全文没有提到“开本”，可能需要在术语表或者正文解释一下这个术语

「开本」是印刷出版术语。如果觉得没有必要仅这一处使用引入术语，可以改成「成品尺寸」 综上，改成

---

NOTE

基于下述理由，行长必须为文字尺寸的整数倍：

1. 中文排版的基本原则是，除段落最后一行以外，每行行尾应对齐
2. 中文排版所用的文字（包括汉字、标点），其字框的设计原则是正方形
3. 中文排版的排字原则是，文字应为密排

作为总体原则，行长应依照不同字体、版式、成品尺寸以及媒介种类、根据实际情况设置。一般来说，报纸期刊的行长相对较短，而书籍的行长较长，但作为参考值，大多数书籍的正文行长一般设在 17 到 40 字范围区间。为避免阅读时频繁换行、串行等情况，正文行长最小不宜少于 10 字、而横排最大行长不宜长于 48 字、竖排不宜长于 55 字。

[xfq]

Discussions in yesterday's clreq meeting: https://www.w3.org/2023/08/08-clreq-minutes.html#t02

[huijing]

基于下述理由，行长必须为文字尺寸的整数倍：

Due to the following reasons, the line length must be an integral multiple of the font size.

1. 中文排版的基本原则是，除段落最后一行以外，每行行尾应对齐
2. 中文排版所用的文字（包括汉字、标点），其字框的设计原则是正方形
3. 中文排版的排字原则是，文字应为密排

1. The basic principle of Chinese typesetting is, with the exception of the last line of a paragraph, the end of every line should be aligned with each other.
2. All characters used in Chinese typesetting (including Han characters and punctuation) are square characters
3. Characters in Chinese typesetting are set solid

作为总体原则，行长应依照不同字体、版式、成品尺寸以及媒介种类、根据实际情况设置。一般来说，报纸期刊的行长相对较短，而书籍的行长较长，但作为参考值，大多数书籍的正文行长一般设在 17 到 40 字范围区间。为避免阅读时频繁换行、串行等情况，正文行长最小不宜少于 10 字、而横排最大行长不宜长于 48 字、竖排不宜长于 55 字。

As a basic principle, the line length should be set according to the actual conditions, which could be the usage of different fonts, design of the type area, trim size or media types. Generally, the line length for newspapers and periodicals is relatively shorter, while the line length for books is longer. For the sake of reference, most books have line lengths of body text in the range between 17 to 40 characters. To prevent excessive line breaks that could cause difficulty in reading, the line length of body text should not be less than 10 characters. For horizontal writing mode, the line length of body copy should not exceed 48 characters. For vertical writing mode, the line length of body copy should not exceed 55 characters.

Update: Ready for PR.

[xfq]

作为总体原则，行长应依照不同字体、版式、成品尺寸以及媒介种类、根据实际情况设置。一般来说，报纸期刊的行长相对较短，而书籍的行长较长，但作为参考值，大多数书籍的正文行长一般设在 17 到 40 字范围区间。为避免阅读时频繁换行、串行等情况，正文行长最小不宜少于 10 字、而横排最大行长不宜长于 48 字、竖排不宜长于 55 字。

As a basic principle, the line length should be set according to the actual conditions where the type is being set, which could be usage of different fonts, formatting structures, product sizing or media types. Generally, the line length for newspapers and periodicals are relatively shorter, while the line length for books are longer. For the sake of reference, most books have line lengths of body text in the range between 17 to 40 characters. To prevent excessive line breaks that could cause difficultyin reading, the line length of body text should not be less than 10 characters. For horizontal writing mode, the line length of body copy should not exceed 48 characters. For vertical writing mode, the line length of body copy should not exceed 55 characters.

Some suggestions:

As a basic principle, the line length should be set according to the actual conditions where the type is being set, which could be the usage of different fonts, design of the type area, trim size or media types. Generally, the line length for newspapers and periodicals is relatively shorter, while the line length for books is longer. For the sake of reference, most books have line lengths of body text in the range between 17 to 40 characters. To prevent excessive line breaks that could cause difficulty in reading, the line length of body text should not be less than 10 characters. For horizontal writing mode, the line length of body copy should not exceed 48 characters. For vertical writing mode, the line length of body copy should not exceed 55 characters.