In a mailing list discussing CSS for formatting text in web pages, italicizing and slanting are now hot topics. It seems that Koji Ishii's message entitled Synthesizing oblique, to which direction in RTL and vertical flow? dated February 4, 2013 was the beginning of the discussion. The discussion has been further developed, and more details have been covered. In this article, however, I would like to avoid jumping into details, but I would like to clearly set forth my view about basic issues only, because I think it will be much easier for us to understand fine details, if we can clarify basic points first.
What is the issue?
The issue that the author of the message of the URL above raises can be summarized as follows:
In the CSS Fonts Module Level 3, the font-style property can have three valules: "normal", "italic" and "oblique", but this means:
Here, the issues are the following two points:
In the following paragraphs, I would like to set forth my thoughts about these.
Italicizing in Japanese typography
The font-style property is defined to have one of the following three values: normal, italic, and oblique. This means that in Western typography, the normal style is thought to be the most standard font-style, and also that the font-style property is meant to be used for enabling the Western typographic convention of switching the font-style from normal to italic, in order to emphasize part of text or to differentiate book titles in bibliographic descriptions, though the normal style, which is typically the upright roman style, is always used as the default style.
Therefore, the value of italic in the context of this property, is always the italic style that is enabled and paired with a pre-existing font in the normal style, and used as the alternative and secondary glyph style. This italic style constrains the font-style property only. This constrains the scope of the italic fonts that can be used, but the existence of the normal style is always assumed. This is the meaning of the font-style property. The same thing applies to the other non-normal value oblique. It specifies the oblique style that is paired with the normal style. The reason why the oblique value is needed is that depending on the typeface design, it is possible that no italic glyphs are available, but only oblique glyphs are available. However, such oblique glyphs can be paired with the normal style, as the function of the oblique style is the same as that of the italic style that can be differentiated from the normal style as the most widely accepted secondary style.
In short, the font-style property is meant to specify the distinction between the normal and the italic (or oblique) styles. The value oblique is meaningful only as the best substitute for the italic style, used when the italic style is not available. So, it is unchanged that the chief purpose of the property is for the sake of "italicizing".
What does "italicizing" mean in Japanese typography and for Japanese fonts made to support Japanese characters and glyphs? It has no other meaning other than to italicize Latin alphabet glyphs, when Latin alphabet characters and Japanese characters are mixed in a context where the Japanese language is the dominant language. The reason for this is simply that the Japanese writing system and its gyphs have no italic style at all. The italic style has not existed historically in the Japanese writing system and typography, and there is no rationality and necessity of using the italic style in Japanese text. On the other hand, in Western typography, switching between the normal and italic syles is a widely accepted convention. Usually, if not always, most Western typefaces have both normal and italic (or oblique) fonts. But this does not apply to Japnese typefaces and fonts at all. It is unclear what functional effect is intended by italicizing Japanese glyphs including Chinese characters and kana syllabic characters. Therefore, italicizing Japanese glyphs is a nonsense operation, unless it is applied only to Latin alphabet glyphs included in Japanese text.
If so, how should we treat a vertical Japanese glyph whose font-style is specified to be italic or oblique? The answer is simple. Do nothing. We can do nothing. This is my answer to the qusetion no. 1 mentioned above. Furthermore, it is self-evident that the same thing applies to both of the horizontal and vertical writing modes.
Thinking this way, we can also see that the question no. 2 mentioned above is itself a meaningless question. In a context in which italicizing has meanigful semantics (and the italic style is intentionally specified), it is impossible to assign the italic style property to any Japanese glyphs, and it is impossible to make a Japanese glyph work as a substitute for italic type, by any means (incl. aritificially transforming and slanting the glyph shape, etc.), because no stylistic usage of italic glyphs exist for Japanese glyphs. Italicizing independently works for Latin alphabet glyphs correctly. It has nothing to do with Japanese glyphs. It is impossible to convert any Japanese glyphs into the shapes that were originated in early 16th century Italian typography.
Also, it is impossible to change the assumed context in which "itaicizing" is intended, to anything else, in which an artificial slanting operation is intended, because the use of the font-style property assumes that multiple values for the property such as normal and italic are available at least, even with exceptions, and this is the reason why it is allowed to apply an artificial slanting transformation to normal Latin alphabet glyphs, if its italic version is not available exceptionally. But italicizing Japanese non-Latin glyphs is simply nonsense. (However, if a Japanese font contains italic Latin alphabet glyphs, it is no nonsense to apply the italic or oblique style to such Latin alphabet glyphs in the font, and today it is possible with the help of a GSUB feature. Still, it doesn't mean that Chinese and Japanese glyphs could be italics).
In other words, we all know that there are typefaces whose names include the word "italic", such as Adobe Garamond Italic. But we don't know if there are Japanese fonts whose names include the same word. Does Kozuka Mincho Regular Italic exist? No, it doesn't. This clearly shows that the differentiation between the normal (or roman) and italic styles is not a widely accepted method of glyph style differentiation in Japanese typography.
Slanting in Japanese typography
I have mentioned how meanigless and impossible the italic font-style in Japanese typography is. Japanese fonts cannot have any italic font-style. However, this does not mean that any slanting transformation effects cannot be used in Japanese typography. In fact, when manual phototypesetting machines with optical-lenses were used, the special effects of Condensed, Vertically-compressed, and Slanted were widely used. Yes, slanting is possible in Japanese typography, but we should pay attention to the following points:
Conclusions
Based on what I have written above, my conclusions can be itemized as follows:
Taro Yamamoto
2013.06.02