- From: Chris Lilley <chris@w3.org>
- Date: Thu, 10 Nov 2005 09:20:14 +0100
- To: Cameron McCormack <cam-www-svg@aka.mcc.id.au>
- Cc: www-svg@w3.org
On Wednesday, November 9, 2005, 5:49:41 AM, Cameron wrote: CM> Hi. CM> SMIL Animation states[1]: CM> It is recommended that language specifications disallow manipulation CM> of animation element attributes through DOM interfaces after the CM> document has begun. CM> [...] CM> Dynamically changing the attribute values of animation elements CM> introduces semantic complications to the model that are not yet CM> sufficiently resolved. This constraint may be lifted in a future CM> version of SMIL Animation. CM> but in SVG 1.1[2]: CM> Unlike other SVG DOM interfaces, the SVG DOM does not specify CM> convenience DOM properties corresponding to the various language CM> attributes on SVG's animation elements. [...] The current method for CM> accessing and modifying the attributes on the animation elements is CM> to use the standard getAttribute, setAttribute, getAttributeNS and CM> setAttributeNS defined in DOM2. CM> which seems to imply that modifying the animation related attributes on CM> SVG animation elements is supported. It is, very much, supported. We found the restriction both undesirable and unenforceable, so we ensured that manipulation of attributes through script mid way through an animation was well specified. in fact, it needs to be anyway because you can have multiple concurrent animations on the same attribute. CM> Is this the case? If so, have the CM> "semantic complications" been resolved? SMIL 2.0 (which I realise isn't CM> referenced by SVG 1.1, but at least might give an indication of what is CM> the right thing to do) still leaves it as undefined[3]. SMIL 2.0 pulled out the early work on a SMIL DOM, which was still in SMIL Animation and was further developed in SVG 1.1. The people producing SMIL 2.0 players were not very interested in scripting, and for their simple 'media player' use cases it wasn't that big a priority. CM> Also, in case an errata document is ever produced(!), of course CM> there is a slight CM> error in http://www.w3.org/TR/SVG11/animate.html#InterfaceTimeEvent CM> where the text "defined in SMIL Animation: Supported interfaces" is CM> repeated. Thanks! CM> Thanks, CM> Cameron CM> [1] CM> http://www.w3.org/TR/smil-animation/#Integrating-ConstraintsOnAttributes CM> [2] http://www.w3.org/TR/SVG11/animate.html#InterfaceSVGAnimationElement CM> [3] CM> http://www.w3.org/TR/2005/REC-SMIL2-20050107/smil-timing.html#Timing-DOMAttributes -- Chris Lilley mailto:chris@w3.org Chair, W3C SVG Working Group W3C Graphics Activity Lead Co-Chair, W3C Hypertext CG
Received on Thursday, 10 November 2005 08:20:16 UTC