Re: [css3-2d-transforms] Interop: matrix() values e,f <number> or <length>

On Nov 19, 2010, at 10:40 AM, Tab Atkins Jr. wrote:

> On Fri, Nov 19, 2010 at 10:26 AM, Chris Marrin <cmarrin@apple.com> wrote:
>> This brings up a glaring problem with CSSMatrix. When you construct one, it is not associated with any element, so you can't use an element's style to convert units. Today, when we encounter the above CSSMatrix constructor I believe we just convert 50% to a value of 50 or something equally arbitrary. We should probably amend CSSMatrix to allow an element to be passed to the constructor.
> 
> Agreed.
> 
> 
>> This brings up the next sticky issue of what happens when, for instance, the client size of the element changes. Do values in the CSSMatrix change? Madness!
> 
> No; the matrix generated should be a static snapshot of values at the
> time it was generated.  Anything else is indeed madness.  ^_^

Yes, a snapshot, but how do we convert units like '%' to some rational value when we're taking that snapshot? That's why I think passing an element is important (in some cases).

-----
~Chris
cmarrin@apple.com

Received on Monday, 29 November 2010 15:14:27 UTC