Re: getFrames should return a sequence<ComputedKeyFrame> or something

(2014/04/16 15:45), Boris Zbarsky wrote:
> Right now getFrames is defined as returning a sequence<KeyFrame> but
> talks about storing something "in the computedOffset property of each
> frame as a Number".
>
> But KeyFrame has no computedOffset property.  This text seems to be
> confusing a WebIDL dictionary with what you get after converting it to a
> JS value.
>
> What you probably want here is a ComputedKeyFrame dictionary which
> inherits from KeyFrame and has a computedOffset member, which you could
> then set.

Yes, that text seems wrong.

I think we could just add computedOffset to KeyFrame. We already ignore 
any computedOffset property when converting an ECMAScript object to an 
IDL KeyFrame.

We added computedOffset because some people commented that they wanted 
to be able to see how the UA was arranging their keyframes (since there 
is some auto-spacing behaviour). So it's output only. However, we also 
want to be able to allow authors to say, for example:

   animA.effect.setFrames(animB.effect.getFrames());

So that's why we added the 'ignore computedOffset on input' step.

What do you think?

Brian

Received on Thursday, 17 April 2014 06:13:35 UTC