Jukka K. Korpela wrote: > (The discussion started under the heading "font-family font sizes", but I > now changed the Subject to more specific.) > > On Fri, 18 May 2007, Bruno Fassino wrote: > > >> Putting together the above, if we trust Gecko, the aspect ratio of a >> font can be obtained simply observing the size of an element >> dimensioned using 'ex' units. >> > > The results are consistent with those I got with my simplistic method that > compares the letter x in large font size with a stickyard. See > http://www.cs.tut.fi/~jkorpela/x-height.html > > It seems that different ways lead to the same results, implying that the > figures mentioned in CSS specifications are wrong - most notably when > they say that Verdana has an aspect ratio of 0.58, but it actually has 0.545. > > This, as well as methods of finding out the x-height value for specific > fonts, is of some importance to authors who wish to use font-size-adjust > (which helps on Firefox 2 and does no harm when it doesn't). > > I don't think you can rely on the size of elements dimensioned in ex units. Eric says in his book that many user agents get their value for ex by taking the value of em and dividing it in half. This is because most fonts don't have the value of their x-height built-in, and it's difficult to compute, as you discovered. Since lowercase letters are about half as tall as uppercase letters, user agents assume that 1ex is equal to .5em.
Also, would monitor resolutions or dot pitch have any impact on your calculations? Since you are taking a ratio, I wouldn't think so, but I wonder... Lori ______________________________________________________________________ css-discuss [EMAIL PROTECTED] http://www.css-discuss.org/mailman/listinfo/css-d IE7 information -- http://css-discuss.incutio.com/?page=IE7 List wiki/FAQ -- http://css-discuss.incutio.com/ Supported by evolt.org -- http://www.evolt.org/help_support_evolt/
