On Apr 4, 2007, at 7:31 PM, Vladimir Vukicevic wrote:
Maciej Stachowiak wrote:
CSS Timed Media Module proposal - http://webkit.org/specs/
Timed_Media_CSS.html
Some feedback on my initial reading.. the CSS properties specified
seem like a good set that will cover most common functionality.
Some comments about the spec, though:
Thanks for reading over this part.
1. 'media-loop-count' is an awkward name, especially with "The
default value of 1 means the item will play through once but will
not loop." We went through this with APNG, and ended up renaming
that member. I would suggest 'media-play-count' instead -- that
way there is no ambiguity with what the number means.
We considered 'media-repeat-count' instead of 'media-loop-count', but
that turned out to be more confusing. We really wanted all the
looping-related properties to have consistent naming, and I don't
think 'play' would work in the other places mentioned.
2. The descriptions for 'media-loop-start-time' and 'media-loop-end-
time' don't match; start-time says "sets the time at which the
media item begins playing after looping", and end-time says "sets
the time at which the media item loops for the second and
subsequent repetitions".
I would suggest that start-time says "sets the time index at which
the media item starts playing for the second and subsequent
repetitions", and that end-time says "sets the time index at which
the media item ends playing for the second and subsequent
repetitions." The language for end-time is still a little awkward,
since "ends playing" could imply that it simply stops playing (and
does not loop), but it's clearer than before.
I think the language might have ended up actually defining it wrong.
The intent of 'media-loop-end-time' is that this is the point where
you end where repeating, but on the last iteration you go all the way
to 'media-end-time'. So if 'media-loop-count' has a value of 3, the
three repetitions would go as follows:
media-start-time ===> media-
loop-end-time
media-loop-start-time ===> media-
loop-end-time
media-loop-start-
time ===> media-end-time
I'll update the spec.
3. 'media-timing' I would get rid of completely; while a shorthand
would be useful, I don't think that media-timing as specified
really works. Shorthands for properties such as 'background' are
understandable on their own; 'media-timing: playing 0s -0.5s 2 2s
-4s 1' is very opaque. If it's still desirable, I would remove
the setting of start/end times and change the volume shorthand to
only accept the symbolic names; e.g. 'media-timing: playing high
4;'... but I think that removing the shorthand entirely would be
preferable.
I'll reply in more detail about media-timing in a later message.
Regards,
Maciej
