[SVGMobile12] What is the point of section 3 ("Rendering Model")?

Section 3 ("Rendering Model") is very vague, much too vague to be 
implemented by user agents in an interoperable way.

The section is written so as to be a single normative conformance criteria 
("the result [of] the implementation SHALL match that described [here]") 
but it is not clear which parts of the chapter are actually intended that 
way and which are intended to merely be expository.

Examples of the vagueness of the definition include section 3.3, wherein 
the paint order is defined such that "the first element is painted first", 
without defining "first" (depth-first? breadth-first? pre-order? in-order? 
post-order? alphabetical? z-index property?), and is section 3.4.1, where 
the requirement is that "the fill is painted first, then the stroke", 
without defining how the paint operations are performed.

The rest of the chapter consists either of incomplete introductory 
material (e.g. section 3.4 omits foreignObject from its list of graphic 
elements, as mentioned in other last call comments; section 3.5 doesn't 
say anything about how the parent compositing is performed or even if that 
compositing is to be done by the SVG processor or if it is outside the 
scope of the spec), or of links to other sections (e.g. 3.2, 3.4.2, 3.4.3 
merely link to later definitions).

Please either remove this section or rewrite it so that it actually 
clearly states what it is intending to state, with testable, implementable 
conformance criteria.

Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

Received on Friday, 20 May 2005 12:06:55 UTC