Personal experience
-------------------
I wish there's a more convenient name for the loader even though it's
already defunct. I would briefly call it "the loader" in the following. My
experience with the loader has been very frustrating. First, nodes supported
are kept on a functional level. Second, the parser has serious limitation.
Third, there's no JavaScript implementation (well, this is actually
equivalent to the first point). Fourth, the source code is a mess. Fifth,
performance is unacceptable. Sixth, navigation and interaction is awkward.
Results in a sketchy form
-------------------------
After a year of grappling with the code, I have come out with my
modification that can parse relatively complex scene, supports JavaScript,
has better text support etc. As a matter of fact, my intention is to
implement Living Worlds. However the outcome is not what I expected, as can
be seen from the screen shots below:
http://members.tripod.com/ywlaw/vr/bee-tilted-wave.png
http://members.tripod.com/ywlaw/vr/bee-tilted-wave-back.png
The screen shots clearly show a wave plane gone awry -- reason unknown.
Apart from this visual artifact, the performance is disappointing. I've had
to disable all animation to get a smooth interaction. Of course it can be
argued that my modification has deteriorated its initial performance to its
current level, but since the initial loader isn't able to parse the sceen at
all, comparison can't be made. (The reason that the initial loader can't
parse the scene is due to the heavy use of PROTOs, JavaScript in the scene.)
Thoughts
--------
While there have been a lot of talks on advanced graphics techniques like
collision detection, particle system on the mailing list, none of these have
ever made their way to the loader. I fully realize all development has gone
to X3D, but the VRML97 part of X3D has never seen any improvement as far as
I can tell. While there have been a lot of questions on the use of the
loader, there hasn't been any significant effort to try explaining the cold
hard facts -- that the loader isn't ready for any serious application. Of
course, tagged as a reference implementation, we shouldn't expect much from
it. Therefore I'm tempted to call for an alternative open source
implementation. In fact, since there have been calls for an open source
implementation of Java 3D itself, why not a VRML loader?
Footnote
--------
(1) The scene is a part of the Tpresence Holodesk package
(http://www.holodesk.com/hd/download/index.html), a virtual world called
Avalon Reef.
(2) The navigation interface contributed by Laszlo Seregi
(http://www.external.hrp.no/vr/) is excellent, thanks Laszlo.
Best regards,
LAW, Yee Wei
http://www.ntu.edu.sg/camtech
Tel: +65 790 4201
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