- From: John Daggett <jdaggett@mozilla.com>
- Date: Mon, 18 May 2009 22:03:18 -0700 (PDT)
- To: Thomas Phinney <tphinney@cal.berkeley.edu>
- Cc: www-style <www-style@w3.org>
Thomas Phinney wrote: > There are probably other issues with this chart lookup, but the one that > leaps to mind is assuming that all fonts will have values that fall in > nice even 100s. Other values are not terribly unusual (for various > reasons mostly related to application architecture limitations on > Windows). I realize that the implementation details of this can get messy and the rules for mapping weights onto this 9-point scale are not always clear. For fonts available on a given system, most user agents rely on platform API's to determine these mappings. GDI has its mappings, ATS a slightly different set of mappings and fontconfig another set. The spec wording already alludes to the problems of mapping a given scale onto this 100 - 900 scale: > Font formats that use a scale other than a nine step scale should map > their scale onto the CSS scale so that 400 roughly corresponds with a > face that would be labeled as Regular, Book, Roman and 700 roughly > matches a face that would be labeled as Bold. Or weights may be inferred > from the style names, ones that correspond roughly with the scale above. > The scale is relative, so a face with a larger weight value should never > appear lighter. If style names are used to infer weights, care should be > taken to handle variations in style names across locales. Is there a better wording for this? One that would reflect common practice in greater detail? Just as an example, ATS on Mac OS X uses the style name to do this mapping or the OS/2 weight if it doesn't recognize the style name. Do you think the spec needs this level of detail, along with a way of specifying how to map weights like 275 or 650? Given your knowledge of Adobe fonts, I'm wondering if you have any insight into why weights that are not multiples of 100 are used in general. Are the reason primarily historical, related to Multiple Master fonts or some sort of hinting consideration? Or GDI-related problems? I analyzed the fonts in Adobe Font Folio 11. Of the 2406 faces, roughly 7% had weights that were not multiples of 100. The breakdown is: 250: 18 275: 10 350: 2 450: 8 550: 7 650: 2 750: 72 850: 30 950: 12 Is there a reason for never defining font weights lower than 250? Listed below are the weights for the HelveticaNeueLTStd family. Why do the Thin and UltraLight faces use 250 and 275, instead of 100 and 200 as suggested in the OpenType spec for faces called "Thin" and "UltraLight"? OS/2 weight class definitions: http://www.microsoft.com/typography/otspec/os2.htm#wtc Weights for faces in HelveticaNeueLTStd family (based on OS/2 weight class): 250 HelveticaNeueLTStd Thin 250 HelveticaNeueLTStd Thin Condensed 250 HelveticaNeueLTStd Thin Condensed Oblique 250 HelveticaNeueLTStd Thin Extended 250 HelveticaNeueLTStd Thin Extended Oblique 250 HelveticaNeueLTStd Thin Italic 275 HelveticaNeueLTStd UltraLight 275 HelveticaNeueLTStd UltraLight Condensed 275 HelveticaNeueLTStd UltraLight Condensed Oblique 275 HelveticaNeueLTStd UltraLight Extended 275 HelveticaNeueLTStd UltraLight Extended Oblique 275 HelveticaNeueLTStd UltraLight Italic 300 HelveticaNeueLTStd Light 300 HelveticaNeueLTStd Light Condensed 300 HelveticaNeueLTStd Light Condensed Oblique 300 HelveticaNeueLTStd Light Extended 300 HelveticaNeueLTStd Light Extended Oblique 300 HelveticaNeueLTStd Light Italic 400 HelveticaNeueLTStd Condensed 400 HelveticaNeueLTStd Condensed Oblique 400 HelveticaNeueLTStd Extended 400 HelveticaNeueLTStd Extended Oblique 400 HelveticaNeueLTStd Italic 400 HelveticaNeueLTStd Roman 500 HelveticaNeueLTStd Medium 500 HelveticaNeueLTStd Medium Condensed 500 HelveticaNeueLTStd Medium Condensed Oblique 500 HelveticaNeueLTStd Medium Extended 500 HelveticaNeueLTStd Medium Extended Oblique 500 HelveticaNeueLTStd Medium Italic 700 HelveticaNeueLTStd Bold 700 HelveticaNeueLTStd Bold Condensed 700 HelveticaNeueLTStd Bold Condensed Oblique 700 HelveticaNeueLTStd Bold Extended 700 HelveticaNeueLTStd Bold Extended Oblique 700 HelveticaNeueLTStd Bold Italic 700 HelveticaNeueLTStd Bold Outline 750 HelveticaNeueLTStd Heavy 750 HelveticaNeueLTStd Heavy Condensed 750 HelveticaNeueLTStd Heavy Condensed Oblique 750 HelveticaNeueLTStd Heavy Extended 750 HelveticaNeueLTStd Heavy Extended Oblique 750 HelveticaNeueLTStd Heavy Italic 900 HelveticaNeueLTStd Black 900 HelveticaNeueLTStd Black Condensed 900 HelveticaNeueLTStd Black Condensed Oblique 900 HelveticaNeueLTStd Black Extended 900 HelveticaNeueLTStd Black Extended Oblique 900 HelveticaNeueLTStd Black Italic 950 HelveticaNeueLTStd ExtraBlack Condensed 950 HelveticaNeueLTStd ExtraBlack Condensed Oblique
Received on Tuesday, 19 May 2009 05:03:59 UTC