Re: [css-transforms] Initial value of transform-style

On Jun 6, 2014, at 8:29 PM, Simon Fraser <smfr@me.com> wrote:

> On Jun 6, 2014, at 12:45 AM, Dirk Schulze <dschulze@adobe.com> wrote:
> 
>> Hi Simon,
>> 
>> On Feb 27, 2014, at 8:03 PM, Simon Fraser <smfr@me.com> wrote:
>> 
>>> On Feb 27, 2014, at 10:41 AM, Matt Rakow <marakow@microsoft.com> wrote:
>>> 
>>>>> Simon recently presented a solution at the CSS F2F and posted a document to public-fx [1] to clear some things up.
>>>>> 1: https://docs.google.com/document/d/1mNF7Z67WnnV05RqXa37PmfvRbgAZwj7-h-7Y_uQ_UPE/edit?pli=1#
>>>> 
>>>> Ah, thanks for the pointer.  It looks like the presentation was on the day I wasn't able to make it unfortunately :(
>>>> 
>>>> Simon, how do you feel about the "auto" value vs. using inheritance as I suggested in my other mail [1]?  Right now it sounds like "auto" would act as "inherit, unless a transform is applied in which case flat" which still seems a bit confusing to me.  For example, it seems unintuitive that these two examples would produce different results:
>>>> 
>>>> <div style="transform-style: preserve-3d; transform: rotateX(30deg);">
>>>> <div>
>>>>     <div>
>>>>         <div>
>>>>             <div style="transform-style: preserve-3d; transform: rotateX(30deg);">
>>>> 
>>>> <div style="transform-style: preserve-3d; transform: rotateX(30deg);">
>>>> <div>
>>>>     <div style="transform: scale(1)">
>>>>         <div>
>>>>             <div style="transform-style: preserve-3d; transform: rotateX(30deg);">
>>>> 
>>>> Thanks,
>>>> -Matt
>>>> 
>>>> [1] http://lists.w3.org/Archives/Public/www-style/2014Feb/0783.html
>>> 
>>> Making it inherited is an interesting suggestion; I’d have to think about that. The performance characteristics are obviously a concern for documents with html { transform-style: preserve-3d; } but it’s possible that UAs could avoid allocating additional resources for elements with no 3d-transformed descendants in this kind of content.
>> 
>> It actually sounds very reasonable and the goals of an inherited properties seem to fit with the goals we had in mind with a new value ‘auto’ quite nicely. Did you have more time to think about it?
> 
> Hi Dirk
> 
> I did a little more editing on <https://docs.google.com/document/d/1mNF7Z67WnnV05RqXa37PmfvRbgAZwj7-h-7Y_uQ_UPE/edit?pli=1#> but haven’t had time to finish it off.
> 
> The most recent changes addressed the fact that the previous text resulted in a behavior where a single 3d-transformed element would render in front of everything else on the page, which is not desired behavior (and doesn’t match current implementations). The current text results in a behavior where a single 3d-transformed element only punches through to the front of its CSS stacking context.

So you would think that we can not address the transformed element in front of everything with inheriting transform-style instead of a default (and new) value of ‘auto’? It doesn’t sound like the issue is per se bound to ‘auto’ or inheritance.

Greetings,
Dirk

> 
> Simon
>

Received on Friday, 6 June 2014 20:15:41 UTC