[whatwg] Web Applications and 3D
mattraymond at earthlink.net
Fri Apr 29 06:14:37 PDT 2005
Ian Hickson wrote:
> On Thu, 28 Apr 2005, Matthew Raymond wrote:
>>The problem with a <canvas> solution is that the entirety of the 3D data
>>has to exist within the <canvas> element. If you want multiple elements in the
>>markup to map to a single 3D window, then <canvas> doesn't really work.
> Right, but my question is what's the use case for having objects for your
> 3D world exist in the DOM?
There's also the potential to use XBL to apply special behavior to
specific tags. For instance, instead of having a static Sun in the sky,
you could have it rise and set by using XBL to pull in code that moves
the model and lighting around.
>>>Having said that, there are probably use cases for declarative 3D,
>>>just like there are with declarative 2D. And for those you would use a
>>>dedicated markup language, just like you use SVG for 2D graphics.
>>My point was that I'd like to see a CDF (not the CAD kind, but the W3C
>>kind) that uses XHTML + X3D, or XHTML + CSS + XBL2 + X3D. While I think
>>it has a lot of potential, I don't know enough about how the respective
>>standards to determine would work together. (This is partly because of
>>my lack of knowledge of XBL2 and X3D...)
> If it wouldn't work together, it indicates a problem in the X3D spec (or
> the lack of an appropriate 3D declarative markup language).
> Creating a 3D markup language is somewhat outside the purview of this
> working group, though.
I'm not saying there's a problem with X3D. I'm just trying to make
sure there is a clear idea of how to make XHTML + X3D compound
documents. In other words, I'm trying to find the weak link, if there is
one, and at the moment that seems to be a lack of examples on the Internet.
>>I already knew the HTML. I was kinda hoping to see the CSS/XBL2 part of
>>that equation. That's the part I'm confused about. Does XBL2 have a CSS
>>binding property like XBL 1.0?
> XBL2 doesn't exist yet, but the idea is it will have that, yes.
Good. I don't see nearly as strong a use case for XBL without such
> I don't see people writing 3D games using a declarative format. Maybe for
> the models, as external files that are slurped in (just like external
> bitmaps are used as sprites with 2D canvas), but that's very different
> from having the 3D in the document.
My thinking is that a "3d" context for <canvas> may require
By contrast, something like X3D would require only DOM manipulation,
because the rendering engine would be either a plug-in or part of the
UA. X3D could also use XBL to achieve special effects that a programmer
would otherwise have to code into their <canvas>-based engine. Imagine
LOD, particle effects, fog, et cetera, turned on and off by simply
selecting an alternate stylesheet. (Well, I suppose you could do that
stylesheet thing with <canvas> and XBL, but it wouldn't be pretty.)
>>I mean stuff like having windows that get smaller when they're further
>>back in the Z-order. Perhaps there's a fog effect. You could have
>>various <section> elements rendered within a 3D environment, where the
>>user looks in a specific direction or in a specific place to see the
>><section> inside a 3D environment. Stuff like that.
> That'd just be up to the UA, really.
No, I meant as in the web author implementing that with web
standards, not the UA adding those effects to vanilla HTML5.
More information about the whatwg