I should preface this with the warning that I am not a programmer, so =
take what I have to say with a grain of salt.
>From my fuzzy understanding, I think that the basic problem is this:
In ARToolkit's use of openvrml, Each marker's 3D stuff is a separate =
file - meaning that there are different 'worlds' on each marker. These =
typically loaded when you start up tour ARToolkit application=20
VRML is designed so that there is one 'world' that is parent to the =
geometries and behaviors within it. In VRML, information can be passed
between models via routing overseen by the parent world. Inside a vrml
world, you can have behaviors triggered by proximity of objects or =
VRML doesn't expressly allow for talking between worlds but you can do =
(which can be written inside the .wrl file) or Java.
this list have got some simple scripts to work in ARToolkit) but it may =
possible to use java to set up communication with your main program via =
I am not sure which version of OpenVRML is used in ARToolkit these days, =
it may be possible to get Java working with it with a bit of bashing =
Once a network socket is established, it might then be possible to write =
any exposed field in a vrml model or set up triggers for behaviors or
that you don't have to keep opening up separate java programs every time =
want to change a behavior. This way, the java application is just a =
for the messages and can be left alone once it's established.
Of course, this depends on how well openvrml currently supports this =
corner of the vrml97 specification but the more recent versions 'should' =
Anyone else have any thoughts on this?
(The release of the DART project in the next few months might provide a =
easier way of doing this stuff)
ATR Media Information Science Laboratories
From: Stefan [mailto:sensorama@g ......]=20
Sent: Thursday, 4 December 2003 7:25 PM
To: rodney@a ........
Subject: vrml object manipulation
i have the same problem as you have.
i want to manipulate the loaded vrml file on the fly (i e change color =
single element like a box)
you are sure that it is not possible with the ar toolkit?
i also didnt find a way to do this, but this does not mean that it is =
(i m new to the toolkit)
my first idea was to load several dirfferent vrml objetc at startup and
change the vrml files associatet with a marker, so it would seem to =
only parts in the model.
so my idea was to change the vrml file with artoolkit ( a simple string
search and replace for example to change colors)
then save the manipulated vrml file and reload it on the fly.
so it maybe should be possible to change some parts in the vrml model
without loadeing several different vrml models.
this is what i am actually trying to do...
maybe this is a possibility for you and we can try to get this working