- From: Felix Miata <mrmazda@earthlink.net>
- Date: Sat, 28 Jun 2014 02:49:03 -0400
- To: www-style@w3.org
On 2014-06-26 23:33 (GMT-0700) Bruno Racineux composed: > The Normal/Medium size is always 16px by default for all browsers. Wrong: http://fm.no-ip.com/SS/brunosFontDefaults1406-144Wie6.png Wrong: http://fm.no-ip.com/SS/brunosFontDefaults1406-144L1.png Wrong: http://fm.no-ip.com/SS/brunosFontDefaults1406-180L2.png Prior to the web, fonts were sized almost universally in points, a physical unit of measure. They still are, in print media as we all know, but also, as the images demonstrate, on computer desktops, and in word processing apps used with computers. Some browsers do indeed size their defaults directly in px, but others work out to 16px only by the happenstance that the environmental density either is or is assumed to be 96 DPI. These others size like the rest of the world, in physical points, which may or may not be accurate, but sized thus nevertheless. As points are a physical unit everywhere except in web standards, and in browsers arguably compliant with them, their physical size in px depends on actual physical display px density, which in turn means they won't be 16 angular px unless they're sync'd up to that magic number 96 (or possibly an integer multiple thereof). The images show, if appropriately viewed in an image viewer adjusting them to a physical size matching the original environment, that e.g. in a 144 DPI environment the 12pt default size some browsers used to and others do still ship with works out to 24px, and at 180 DPI to 30px, where px is defined as whatever size the browser may choose call it, if any unit all is presented, most often closer to a device pixel than an angular pixel. The are two basic problems with the widespread assumption that all browsers ship with a 16px default: 1-It isn't and never has been[1] true. 2-Making any assumption at all about either the shipped with size or the size in fact disregards the issue that making any assumption at all is the wrong thing to do, with one very major exception, which is that the default size is presumptively optimal reading size for the person using the browser. If in fact the shipped default is inappropriate, the user is the only one in position to ascertain an appropriate personalization. [1] e.g. charted how they varied in IE6. It's old, so you need browser and DE that adhere to the concept of pt as physical units for the samples to show what they showed when created: http://fm.no-ip.com/Auth/IE/absolute-sizes-IE6.html Netscape 4 and its predecessors, like IE, sized in pt, so their 12pt as shipped defaults were only 16px in an actual or assumed 96 DPI environment. As to $SUBJECT, CSS has already given web stylists an overabundance of power to make life difficult for web users. Limiting the ability of users and their browsers to override disrespectful web styling and maintain some semblance of legibility has no business being any part of web standards. On 2014-06-17 12:59 (GMT-0700) Tab Atkins Jr. composed: > 16px is always (approximately) the same size; it's an absolute unit. As an angular measurement, true. > It does not depend on the pixel density of your device. It doesn't, but pixel density is a part of the real world that the specification ignores. Its use by stylists brings with it assumptions that don't play nicely with usability, accessibility or respect for web users. There's wide variation in proximity between the angular specification pixel and the real world CSS pixel due to the granularity dictated by browser engine and computing power limitations. Web users would be much happier people if the CSS px unit didn't exist, and stylists were forced to use units already at their disposal that are a function of size determined by each individual web user (e.g. em/ex/rem, or fractions or multiples thereof), leaving it up the the browser engines to determine automatically how many pixels to use to achieve them, leaving no need for users to reach for size controls on every first page load of a new domain, or worse. > If it did, all pages would have been broken for years already, since devices > have DPIs ranging from 72 to 300+. The web has had an overabundance of broken pages for well over a decade, nearly as long as CSS has existed, perpetuated by specifications usurping ancient names applicable to physical units of measurement to apply to illogical units of measure. -- "The wise are known for their understanding, and pleasant words are persuasive." Proverbs 16:21 (New Living Translation) Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata *** http://fm.no-ip.com/
Received on Saturday, 28 June 2014 06:49:27 UTC