Re: [CSS21] Why do overflow values other than 'visible' establish a new block formatting context?

On 4/2/2012 11:35 AM, L. David Baron wrote:
> On Monday 2012-04-02 11:24 +0800, Daniel Tan/BoltClock wrote:
>> This leads us to wonder: why is this so? I am under the impression
>> that removing floats from normal flow will interfere with clipping
>> and scrolling, but am not sure how exactly. I can't seem to find any
>> previous threads in the mailing list that discuss the overflow
>> property in particular.
>
> Fundamentally, because if the spec didn't say this, then having
> floats intersect with something that's scrollable would require the
> browser to rewrap (around intruding floats) the contents of the
> scrollable element every time it scrolls.  This is technically what
> CSS 2.0 required, but it was never implemented, and it would have
> been a huge problem for speed of scrolling.
>
> -David
>

This makes sense for 'auto' and 'scroll', but what about 'hidden'? The 
spec says that 'hidden' indicates that overflowing content is clipped, 
and that no scrolling UI should be provided for viewing content that 
gets clipped. Or is 'should' the keyword here, implying that a UA may in 
fact provide a means (scrolling or otherwise) to access content outside 
the clipping region?

-- 
Daniel Tan/BoltClock
NOVALISTIC • Stellar Software Development & Design
<http://NOVALISTIC.com>

Received on Monday, 2 April 2012 04:03:06 UTC