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

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.

I’m currently struggling to figure out how to spec transform-style to avoid an issue noted in that Google doc where a single transformed element renders on top of everything else (but in current UAs, can be obscured by elements with higher z-index).

Simon

Received on Thursday, 27 February 2014 19:03:59 UTC