Re: [css-animations][web-animations] steps() timing function sometimes unintuitive

[Brian Birtles]

On 2016/03/09 7:24, Rachel Nabors wrote:

I was thinking of "steps(5, equal)" when discussing this syntax, as an
expansion of the steps() formula. I think it looks sensible, if that's
possible?


Works for me.

"start" and "end" refer to where the step takes place, while "equal" 
doesn't but actually influence the length of each segment, so it's a bit 
odd. Still, I think it's ok.


If we can't find a suitable keyword to stick into steps(), then another 
option is to mint a completely separate function (e.g. stagger(), 
quantize() etc.).



On Mon, Mar 7, 2016 at 9:00 PM Brian Birtles > wrote:

On 2012/12/21 3:46, Tab Atkins Jr. wrote:
 > On Wed, Dec 19, 2012 at 6:40 PM, L. David Baron
> wrote:
 >> On Wednesday 2012-12-19 10:29 -0800, Tab Atkins Jr. wrote:
 >>> I propose another steps value: step-mid. It splits the
animation curve
 >>> into n segments, makes the first n-1 do step-end behavior, and
leaves
 >>> the last to just run normally.  The above example could instead be
 >>> written as "steps(4, step-mid)" and have this behavior:
 >>
 >> I like the idea, but I find the name confusing; it sounded like
 >> something that would give the first and last steps half the duration
 >> of the other steps.  (I also find the description quoted above
 >> confusing, but the rest of the email made it clear.)
 >
 > I have absolutely no attachment to the name.  It was the first thing
 > that came to mind.
 >
 > I assume that Rachel's suggestion comes from her association of
 > steps(n, end) with meaning "eat the end of the animation" (and
 > likewise for "start"), so "none" is reasonable in that sense.
I'm not
 > sure it makes sense if your understanding comes from the spec's
 > explanation, though, where "end" means "transitions all at once
at the
 > end of the step".
 >
 > Another possibility is just a new function.  I'm not sure what I'd
 > want to name it, though.

I spoke with Rachel and a few others about this recently and we were
wondering about the name step-equal? Unfortunately, that doesn't
translate into a function very well ('step-equal(2)'? Alternatively,
what about 'step-stagger' and 'stagger(5)', or just the function?).

I'd like to settle on this soon because Chrome is shipping
Element.animate() with support for 'step-middle' as defined by Web
Animations.[1] We went to implement this in Firefox[2] but I'm concerned
that there aren't use cases for step-middle as currently specced and
instead what we want is what Tab originally proposed in this thread.

Assuming usage is low in Chrome, I'd like to drop step-middle from Web
Animations and replace it with this revised timing function.

Best regards,

Brian

[1] http://w3c.github.io/web-animations/#typedef-step-timing-function
I didn't realize Chrome had implemented this, or else I would have
brought this up sooner.
[2] https://bugzilla.mozilla.org/show_bug.cgi?id=1248340

Re: [css-animations][web-animations] steps() timing function sometimes unintuitive

[Rachel Nabors]

I was thinking of "steps(5, equal)" when discussing this syntax, as an
expansion of the steps() formula. I think it looks sensible, if that's
possible?
On Mon, Mar 7, 2016 at 9:00 PM Brian Birtles  wrote:

> On 2012/12/21 3:46, Tab Atkins Jr. wrote:
> > On Wed, Dec 19, 2012 at 6:40 PM, L. David Baron 
> wrote:
> >> On Wednesday 2012-12-19 10:29 -0800, Tab Atkins Jr. wrote:
> >>> I propose another steps value: step-mid. It splits the animation curve
> >>> into n segments, makes the first n-1 do step-end behavior, and leaves
> >>> the last to just run normally.  The above example could instead be
> >>> written as "steps(4, step-mid)" and have this behavior:
> >>
> >> I like the idea, but I find the name confusing; it sounded like
> >> something that would give the first and last steps half the duration
> >> of the other steps.  (I also find the description quoted above
> >> confusing, but the rest of the email made it clear.)
> >
> > I have absolutely no attachment to the name.  It was the first thing
> > that came to mind.
> >
> > I assume that Rachel's suggestion comes from her association of
> > steps(n, end) with meaning "eat the end of the animation" (and
> > likewise for "start"), so "none" is reasonable in that sense.  I'm not
> > sure it makes sense if your understanding comes from the spec's
> > explanation, though, where "end" means "transitions all at once at the
> > end of the step".
> >
> > Another possibility is just a new function.  I'm not sure what I'd
> > want to name it, though.
>
> I spoke with Rachel and a few others about this recently and we were
> wondering about the name step-equal? Unfortunately, that doesn't
> translate into a function very well ('step-equal(2)'? Alternatively,
> what about 'step-stagger' and 'stagger(5)', or just the function?).
>
> I'd like to settle on this soon because Chrome is shipping
> Element.animate() with support for 'step-middle' as defined by Web
> Animations.[1] We went to implement this in Firefox[2] but I'm concerned
> that there aren't use cases for step-middle as currently specced and
> instead what we want is what Tab originally proposed in this thread.
>
> Assuming usage is low in Chrome, I'd like to drop step-middle from Web
> Animations and replace it with this revised timing function.
>
> Best regards,
>
> Brian
>
> [1] http://w3c.github.io/web-animations/#typedef-step-timing-function
> I didn't realize Chrome had implemented this, or else I would have
> brought this up sooner.
> [2] https://bugzilla.mozilla.org/show_bug.cgi?id=1248340
>