Re: [web-animations] confusing picture for player limiting behavior

Aleksei Semenov <a.semenov@unipro.ru> писал(а) в своём письме Wed, 18 Feb  
2015 14:06:58 +0600:

> Brian Birtles <bbirtles@mozilla.com> писал(а) в своём письме Wed, 18 Feb  
> 2015 12:27:23 +0600:>>
>
>>> The section '3.5.11. Reaching the end' describes the player behavior,
>>> when it reaches its boundaries (either start or finish).
>>> The section also contains a picture to demonstrate the effect of  
>>> limiting.
>>> (Please, find it attached)
>>> The description of the picture reads
>>>> The effect of limiting the current time of a player with a start time
>>>> of 1s,a source content of length 3s, and a positive player playback
>>>> rate.After the current time of the player reaches the end of the
>>>> source content, it is capped at 3s.
>>>
>>> I think the picture is not correct in the area, where timeline time is
>>> before player start time.
>>> First, the curve contains the arrow as if playback rate is negative,  
>>> but
>>> description states it is positive.
>>
>> Sorry, I don't understand this point. Why do you suggest the playback  
>> rate is negative? Timeline time and player time both increase and  
>> decrease in proportion. If the playback rate were negative the curve  
>> would slope in the opposite direction since an increase in timeline  
>> time would cause a decrease in player time.
>
> The curve contains an arrow at each end.
> In my opinion, the arrow corresponds to playback rate:
> timeline time value always increase monotonically,
> while player time value increase or decrease, depending on playback rate.
> The arrows point in the opposite directions.
> So I believe, the arrow corresponding to negative playback rate
> do not match with picture description and is redundant and confusing.
> It points to South-East on the picture.

I am sorry, it should be read as South-West.

After second thought, I think that you are right.
There is no good reason to relate this arrow (pointing at South-West)
with negative playback rate. For negative playback rate it should
point to South-East.
I think, this fact only enforces my point, that second arrow is confusing
and should be removed.

Thanks,
Aleksei.

Received on Wednesday, 18 February 2015 10:26:16 UTC