Re: Initial commit of 2D Transforms draft

Hi Anthony,

On 11/05/2010, at 3:15 PM, Anthony Grasso wrote:

> Hi FX TF,
> I have started the interesting process of merging the CSS 2D Transforms spec and SVG Transforms chapter together. The initial (and very rough draft) of the document has been committed to the FX archive [1].
> There is an FX telcon about a week from now, if people can have a look at the draft before then that would be great. I would like to discuss at the telcon what further changes need to be made with the document to complete the initial merge.

I cannot make the call (the time is fine but I have a conflict on Mondays), so here are some comments.

As you say, this is a first draft, so I expect you were going to get around to these soon anyway.

- I think you need code examples for the nested transforms section

- There is some crucial text missing regarding CSS transforms. This was badly placed in the introduction of the CSS specification (it should be in its own section... and rewritten):

"The transform property does not affect the flow of the content surrounding the transformed element. However, the value of the overflow area takes into account transformed elements. This behavior is similar to what happens when elements are translated via relative positioning. Therefore, if the value of the ‘overflow’ property is‘scroll’ or ‘auto’, scrollbars will appear as needed to see content that is transformed outside the visible area.
Any value other than ‘none’ for the transform results in the creation of both a stacking context and a containing block. The object acts as a containing block for fixed positioned descendants."

- The section on transform animation and matrix decomposition needs to be added. I'm sure Dr Olaf will disagree about the specifics. SVG/SMIL has never described in detail how a transformation should be animated.

- You should probably make it clear that transforms accumulate over the language boundaries. ie. an SVG element inside HTML content does not reset the CTM.

- We suggest adding an "identity" transform function, that can be used as a match to anything in the animation rules. The benefit is that it allows you to specify a transform (and hence establish a stacking context) without having to specify the identity transform in terms of something else. We've been meaning to add this to CSS for a while.

> Please note, my knowledge of the CSS model is no where near as advanced as people CSS WG. Thus, we need to assign an editor from the CSS group in addition to myself. Any takers?

Simon and I volunteer.


> Cheers,
> Anthony
> [1]

Received on Monday, 17 May 2010 18:58:28 UTC