NatNet Streaming Client reading data from Arena?

[BernhardSp]

Hi,

I am trying to stream from Arena to a real-time character animation application that is based on Cal3D.
I compiled the Streaming Sample Distribution Files from
http://www.naturalpoint.com/optitrack/s ... #streaming
to see if I can connect to Arena and to read mocap data from it.
The application compiled fine and it also connects to the Arena server with the following message:
Connecting to server at 127.0.0.1...Connected.
Client IP: myip
Server IP:127.0.0.1
Server Name:localhost
Client is connected to server and listening for data...

where I replaced the actual ip with "myip".
Unfortunately when I debug the application the DataHandler callback function that is registered by using theClient.SetDataHandlerFunc(DataHandler );
is never called.
DataHandler is not called if I play back a recorded skeleton animation either.
I activated the Stream Frames in the "Other" tab for the "MB Plugin" in Arena and entered as IP address "127.0.0.1".
Is it generally possible to stream from Arena to the NatNet example client application??
Do you have any ideas as to what I may be doing wrong?


Many thanks,
Bernhard

[VincentG]

I talked with the development team this morning about this, and it maybe a difference between the different versions of Natnet. We are currently updating that part of the software, and hope to have it sorted out shortly......

[BernhardSp]

Hi,

I found two versions of NatNetLib.dll the one installed with the motionbuilder plugin and the other with the streaming sample client.
The one in the motionbuilder plugin has a modify date of 14 May 2007 and the one that comes with the streaming example application has a modify date of 20 September 2007.
The sample application was posted 3/13/08.
Both versions behave the same.
I used the NatNetHelper::NatNetVersion function to find out what version of NatNet I am using.
It returns the same for the dll from motion builder and for the one in the streaming sample client.
However the values it returns are different depending on the computer that I am using.
I am using the latest Arena version 1.1.034.

I haven't tested the motionbuilder plugin yet, but assuming it works I guess it would use the Natnet version of the NatNetLib.dll in the motion builder plugins director???

Many thanks,
Bernhard

[Birch]

There appear to be some versioning issues with the sample on the website when used with Arena, we are looking in to this. We apologize for the confusion.

[Birch]

Hello,

We have posted new installers for Arena (1.2.034 beta 02) and the Tracking Toolkits (1.1.034 Final D), they include harmonized NatNet versions. A matching NatNet SDK (version 1.4) is also posted. It includes some additional samples as well

[BernhardSp]

Hi,

I have adapted my client to the new NatNet SDK.
I can now animate Cal3D avatars in real time based on whole body tracking data in our XVR virtual reality system.

This is fantastic news!

Thanks a lot,
Bernhard

[BernhardSp]

Hi,
I was trying to get the raw 3D marker positions from Arena through the NatNet SDK 1.4.
Unfortunately if there is no skeleton or rigid body defined then no data is received on the NatNet client even though the 3D markers are displayed nicely in arena and their Id and position can be shown.
Is there any way to receive that raw 3D Marker data from Arena if no skeleton or rigid body is defined?
If not is there any way to extract the 3D Marker data from .pt2 files and save it just as an array of positions changing over time?

Also I noticed in the example client of the NatNet SDK 1.4 commands such as
"UnitsToMillimeters"
or
"TestRequest" are sent by using the SendMessageAndWait function.
I couldn't find any documentation on these commands.
Are there any others?
Do you have a documented list of commands available for the Arena NatNet Server?

Many thanks for your help,
Bernhard

[VincentG]

For the first part of your post -

The Arena software is not capable of streaming untracked 3d markers, that are not part of a rigid body, or skeleton.

http://www.naturalpoint.com/optitrack/p ... rison.html


As for the secong part, if will defer to the development team on this one......