Re: [CSS21] Issue 149 - px vs. pt

On 06/29/2010 06:12 PM, Stephen Zilles wrote:
>
> The point, "pt" is just one of the absolute units that have been long
> defined in CSS2 and have been used in other specs, such as SVG. The
> relationships defined between the absolute units have existed for
> longer than even CSS has existed and breaking that relationship would
> need analysis of more than just CSS files. In particular, SVG files
> are likely to use inches or centimeters for the graphic parts of a
> drawing and points for the textual labels. If these no longer matched
> there would be significant complaints.

If we're talking about precedence, the mapping of 1mm to one millimeter
is a much older convention (200+ years, with no significant variance
in definitions) than the mapping of 72 points to the inch (~30 years?,
with multiple alternative systems also in existence, e.g. Didot points,
TeX points, etc.). :)

The point about SVG, however, is important.

XSL:FO at least does not have this problem. They have very precise
definitions for their length units. http://www.w3.org/TR/xsl/#d0e5752

~fantasai