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Re: [csswg-drafts] [css-fonts] Proposal to extend CSS font-optical-sizing (#4430)

From: arrowtype via GitHub <sysbot+gh@w3.org>
Date: Mon, 08 Jun 2020 14:47:36 +0000
To: public-css-archive@w3.org
Message-ID: <issue_comment.created-640676629-1591627655-sysbot+gh@w3.org>
Dave’s suggested interpretation for the opsz spec is:

> Scale interpretation: Values can be interpreted as text sizes in 1/96in. Values can be converted to Points (1/72in) by multiplying 0.75x.

I just wanted to state what may have already been said before: this shifts the temporary complexity of change off of browser & OS developers, but turns it into permanent complexity for type designers & mainstream users. I can see why that is appealing in the short term, but preserving browser similarity in the short term shouldn’t justify user pain in the long run.


Nick’s suggestion is:

> 1 opsz unit corresponds to an angular measure of 3 arcminutes, the equivalent of 1 typographic point when viewed from a typical viewing distance of about 16 inches

I agree with the goal of including an interpretation that software/hardware vendors can use. However, I believe this might be simpler to understand & implement if it is modified slightly:

> 1 opsz unit corresponds to 1 typographic point. This is equal to 4/3 of a CSS px unit, or an angular measure of 3 arcminutes when viewed from a typical viewing distance of about 16 inches.

That is, we should prioritize the simple, actionable measures first, because most readers won’t know how to measure 3 arcminutes at 16 inches. (At least, I certainly don’t. I assume it would involved some trigonometry to calculate 1/72 inch?)

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Received on Monday, 8 June 2020 14:47:38 UTC

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