- From: Chris Lilley <chris@w3.org>
- Date: Fri, 03 Dec 1999 18:24:34 +0100
- To: Raph Levien <raph@acm.org>
- CC: www-svg@w3.org
Raph Levien wrote: > > Chris Lilley wrote: > > > > It would be very helpful for the Document Object Model (DOM) working > > group to know of all DOM implementations - in particular, > > implementations of (perhaps part of) DOM 2 - that are available, in this > > case for implementing SVG. > Gill uses our own homegrown DOM implementation, Gdome. That is the one that Daniel Veillard helps with, yes? > Our goals are to > be 100% core DOM1 compatible, and supply enough of the DOM2 functions > for our needs. Not all functionality is currently implemented. Which parts of DOM 2 are implemented? For the unimplemented parts, is it because these are felt to be not useful, or is it the usual reasons (not enough hours in the day, etc) > Gdome is > written in C (as is the rest of Gill - the SVG implementation page > incorrectly has it as C++). Thanks, I will update it. > My personal experience with DOM has been fairly negative so far. When I > started Gill, I was fairly enthusiastic about DOM, and took the approach > of basing the entire implementation around it. However, we ran into some > problems. The event model in DOM2 (last I checked) has serious > limitations that prevent it being really useful for the > Model/View/Controller pattern. Thus, we're looking at having to > implement nonstandard extensions to DOM2 so that Gill can have a clean > MVC architecture. I would certainly be interested to hear any more detail about this. > In addition, DOM per se has lots of potential garbage collection > problems and some other Java-isms. For Gdome, we added ::ref() and > ::unref() methods so that nodes could be reclaimed by reference > counting. So once there are no remaining references the node can be deleted? > Further, Gdome is based on UTF-8 rather than UTF-16 encodings. You mean, internally it is stored as UTF8 (which is fine) or do you mean, there isn't a UTF-16 interface available? > We've played around with CORBA bindings (including, for example, > translating the encoding), but at this point don't feel that DOM over > CORBA is a good solution, due to the distributed garbage collection and > latency problems. > > Hope this is helpful. Very much so, thanks for taking the time to report back on your findings. > Raph > > P.S. I know the Gill webpage is a bit out of date. Somewhat, but I know how it goes. > However, development > is still going strong. Yes. I found the CVS changelog on the Web, which is where the 'last update' date on the SVG Implementation page comes from ;-) > Right now, I'm focussing on making libart (the 2D > graphics engine powering Gill) more robust. I'll be giving a talk on > Gill at Linux Expo Paris 3 Feb 2000, if anyone is interested. Quite possible (I live in France, though South rather than Paris). -- Chris
Received on Friday, 3 December 1999 12:24:39 UTC