What is the slug height of the font?

[SEASONS283724216wp2]

In Adobe manual for Table, "By default, row height is determined by the slug height of the current font." I want to know what the slug heigt of the font means. 

[Peter Kahrel]

As far as I'm aware, fonts don't have a slug height. Cap height, x-height -- yes. But slug height?

Do you have a link to that manual?

[SEASONS283724216wp2]

https://helpx.adobe.com/indesign/using/formatting-tables.html

Resize columns and rows

[Peter Spier]

In metal type, the slug height would, I think, be the point size of the type. How the type desinger chooses to place the glyphs on the slug would be up to them.

Adobe being what it is, though, it wouldn't surprise me if they mean the assigned leading leading value.

[Derek Cross]

The type size of a font is the measurement from the top of the heighest ascender to the bottom of the lowest defender plus a little space to stop the assenders and descenders touching in multi line text. So, for example 12pt is this total depth and  12 on 14pt leading would actually be 2pt leading. In some typeface designs the capital letters are the same height as the lower case assenders and in some designs the lower case assenders are higher than the capitals 

[Peter Kahrel]

You live and learn. Here's a link to an article that says that a font's "em-height originally derives from the height of the metal slug on which each character was contained in traditional mechanical printing." http://benwhitmore.altervista.org/line-spacing-getting-right/

Interestingly, one of the options in anchored frame's Y-relative-to value is EMBOX. It's not exposed in the interface (unlike ascent, cap height, leading, and x-height). Looks as if it was once part of or intended to be part of the interface, but was abandoned was left in the scripting model.

Some expriments show that an anchored object's em-box height is the same as the font's type size. Its position is such that a character's cap heigh is centred in the box:

P.

[Derek Cross]

My description of font sizes was based on metal type. There might well be different calculations used in digital fonts but for ordinary mortals working with fonts, my description IMO be fine for those typesetting with InDesign.

Understanding this is particularly  useful for calculating a base line grid. For example, a 14pt baseline grid (based on 12/14) I have a 7pt baseline grid so I can apply half a line space.

[SEASONS283724216wp2]

https://helpx.adobe.com/indesign/using/creating-tables.html

USING THE CREATE TABLE OPTION

[Peter Kahrel]

@SEASONS283724216wp2 -- Aobe's text -- " (The slug is based on the leading value. In this context, a slug is the approximate height of the highlighting in selected text.)" -- doesn't make much sense since 'slug' has meaning in InDesign's interface only when you set up a page (as in slug and bleeding).  InDesign doesn't have 'slug' as a font metric. You'll have to make do with ascent, cap height, x-height.

[Derek Cross]

Yeah, stick to Font Size and Leading in points and away you won't go far wrong!

[Peter Spier]

OK, I believe I was correct that Adobe calls the type slug the leading value. In metal type, particularly machine set type, one would refer to a type slug as being a single line of type spanning the column, and I think it is equivalent to, more or less, to waht you see as the hiughlighted area when you select a line in InDesign.

As to Ben Whitmore's article, which I only scanned, I think that's confusing. I think one needs to make the distinction between "m height," which is variable and equals the distance from the baseline to the top of a lowercase "m," and "em height." An Em is a unit of measure equal in width to the point size of metal type. I've never heard the term "em height" used before. An em space is one em wide, and with metal type we used to refer to "em quad" spaces which were square in section so couldn't be set wrong way around. An En is equal to one half em. Other fixed-with spaces are also based on the em and are therefore always proportional to the point size of the type in use.

[Derek Cross]

As a matter of interest, in old letterpress printing days, an em space was known as a mutton and an en space a nut.

[rob day]

a slug is the approximate height of the highlighting in selected text

Seems like "approximate" is the operative word. If I set my default point size to 100 and the leading to anything, a new table’s cell height is 92.99 pts, which doesn’t seem to correspond to any combination of font metrics –point size, ascent+descent, capheight, etc—definately not leading:

[Peter Spier]

Gotta love it...