Hi Joshua,
I hacked a fix into the code and found that it works quite well if there is a
mutex locker blocking anything that might change the text in osgText.cpp.
This has been discussed a lot in the past. You can't just run threads
that will go call stuff in OSG at any time. You need to modify most
things during the update traversal (which is essentially what your mutex
ensures). This is indeed a hack.
What I would suggest instead, to prevent threads waiting for one another
and to prevent you setting the text on your osgText object multiple
times between two frames (which can be expensive in my experience, for
something the user will never see) is to have a simple buffering scheme.
1. Your thread can put the text values you want to display in some
holding area (which you would lock to ensure writing to it is threadsafe).
2. An update callback on your osgText object would go get the latest
value in your holding area, compare it with the last value that was set,
and only if it's different will set it on the osgText object.
Your osgText object still has to have DYNAMIC data variance, so that the
viewer knows to hold back the next frame until that object's update is
done. But the advantage of the above suggestion is really that two
threads won't wait for each other, they will really hold the mutex (for
your holding area) a minimum of time. Plus it's less intrusive on your
main loop - you can encapsulate all that in a simple class, and if you
need to add more text objects later, you don't need to add other mutexes
or modify your main loop in any way.
Hope this helps,
J-S
--
______________________________________________________
Jean-Sebastien Guay jean-sebastien.g...@cm-labs.com
http://www.cm-labs.com/
http://whitestar02.dyndns-web.com/
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