- From: John Hudson via GitHub <sysbot+gh@w3.org>
- Date: Thu, 28 May 2020 16:24:42 +0000
- To: public-css-archive@w3.org
> opsz retains the type designerʼs illusion (or, put nicer: informed assumption) that the physical size of the text using their font tells them something about the available output device resolution (e.g. re ink sinks) or its textual role (e.g. heading) in advance. It hardly does. I disagree. The whole point of opsz as currently defined is that it isolates size specific design from thing like resolution and typographic role, in such a way that those can be handled orthogonally (in terms of variable font design space, this might be literally orthogonally). So, for example, I recently delivered Text and Display versions of a typeface to a client, but these are stylistic variants intended for different typographic roles, _not_ opsz variants of a single style. Similarly, the presence and size of ink traps or grade variations is not primarily a matter of size-specific design but of output medium. So if I were building a variable font that I wanted to have control of stylistic features appropriate to different typographic uses, and functional features appropriate to different output media (including possibly different kinds of features for digital display vs print media), I would want those to be independent of the opsz features, the latter being a kind of ideal of size-specific design for high resolution display and high quality offset printing or whatever medium is the target output of a particular project. So opsz doesn't provide a grab-all of features covering typographic role, output resolution, etc., but rather a starting point to which those kinds of features can then be applied. > However, screens are the predominant output medium for browsers and they are anchored on a logical to physical pixel ratio. This, in fact, is an optical measure because unlike physical size it already factors in typical viewing distances. Type designers are also factoring in typical viewing distances when we design for physical size. The adjustments we make for 6pt type vs 36pt type are based on either typical reading distances, or on specific distances if we're designing for e.g. electronic signage displays to be installed in a known location. I'm perfectly okay with the concept of type size anchored on a logical to physical pixel ratio that factors in typical viewing distances. I'm just concerned that this should give type designers a fixed target for optical size-specific design, and this seems to me to be in everyone's interest, because that last thing we should want is some type designers making opsz for Windows, and some for Mac OS, and others for Android. If different platforms are going to handle the logical to physical ratio differently, we'd still want the opsz design work to be based on a common set of 'informed assumptions'. -- GitHub Notification of comment by tiroj Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/4430#issuecomment-635453142 using your GitHub account
Received on Thursday, 28 May 2020 16:24:45 UTC