[css3-values] Thoughts and comments on the unit types and values.

Hi,

1.  The css3-values spec for time units
(http://www.w3.org/TR/css3-values/#time) does not have any examples of
values whereas the other unit types do.

Thus, it is not clear whether a value such as 23.25s is valid or not.

2.  More generally, the unit specifiers (s, kHz, dpi, cm, ...) do not
specify their valid formats. That is, it does not make sense to have
e.g. 0.5Hz, but 0.25kHz is logically possible. Also, are things like
0.1px valid or not?

3.  Looking at the SMIL specification for time (clock) values
[http://www.w3.org/TR/smil/smil-timing.html#Timing-ClockValueSyntax],
it provides a more comprehensive specification of time values that
also cover hours and minutes.

3a. Would it make sense to extend the CSS time units to cover hours
('h') and minutes ('min')?

3b. Would it make sense to add support for the non-unit based time
values covered in the SMIL spec, i.e.:

HHH:MM:SS.mmm
HHH:MM:SS
MM:SS.mmm
MM:SS
SS.mmm
SS

Where HHH is hours, MM is minutes, SS is seconds and mmm is
milliseconds. See
http://www.idpf.org/epub/30/spec/epub30-mediaoverlays.html#app-clock-examples
for example values.

Thanks,
- Reece H. Dunn

Received on Friday, 1 November 2013 13:16:07 UTC