定义网格系统

[xfq]

clreq全文没有提到「网格系统」，不过有一些相关文字：

原则上，中文排版所使用的汉字和标点符号比例皆为1:1的正方形，将其无缝隙并列排成版面。

我们是否需要把「网格」这个术语明确写出来？

[realfish]

应该是有必要的，不过需要一些前置的术语规划。

在英语语境里，grid system（网格系统）所指的对象，容易被理解成是排版/布局中相对「宏观」的规则或模板。大体上，它对应目前 CSS Grid 旨在覆盖的布局需求。

而中文排版的网格，尤其是术语「纵横对齐」以及 1.1 节提到的相关内容，更接近 JLReq 的「基本版面」或 Adobe InDesign 所谓的「版面网格」（layout grid）。后者我早前在 #56 中有简单提到过。

[yisibl]

@fantasai @frivoal Does the CSSWG have a discussion or specification for this?

[frivoal]

The CSSWG has only seriously discussed the grid of lines (block axis), no so much the grid of of characters in the inline axis.

Our first attempt was https://drafts.csswg.org/css-line-grid-1/. However, this is largely stalled, because setting up the grid this way is a little risky, and if things end up being just a little bit too big, it's quite easy to end up with a lot of double spacing. Another simpler attempt was https://drafts.csswg.org/css-rhythm-1/#line-height-step, but it's even more fragile to that problem.

So instead, more recent discussions have focused not really no setting up a grid forcibly, but on better sizing of lines and blocks so that they naturally line up as a grid:

• https://drafts.csswg.org/css-rhythm-1/#block-height helps size blocks so that they're a multiple of the line height
• https://drafts.csswg.org/css-inline-3/#text-edges and https://drafts.csswg.org/css-inline-3/#inline-height helps lines have a more predictable size (note that the spec is not up to date, and that we have resolutions that have not been applied yet: [css-inline-3] It's impossible to use text-box-trim without changing line progression within the paragraph csswg-drafts#8829, [css-inline-3] text-box-trim accumulation csswg-drafts#5426, maybe more)