the position of the emitter in the previous frame and the new position in the new
frame, the number of particles added also scales up to compensate for this movement.
email from Marco)
"Most relevant news:
1) particle systems now have the "freezeOnCull" property set to false by
default. Since it is an optimization, and using it may cause some unwanted
behaviors if not handled properly, it makes more sense to turn it off by
default.
2) new "LINE" shape mode which uses GL_LINES to draw line segments that
point to the direction of motion.
3) particles can now have a rotation angle and angular velocity.
4) new AngularAccelOperator applies angular acceleration to particles.
5) particle processors such as emitters and programs can have a "start",
"end" and "reset" time coordinate. For example, an emitter may be instructed
to start emitting particles only after a certain time, stop after another
amount of time and then start again.
Update (2) is from Gideon May.
Updates (3) to (5) are from Douglas A. Pouk."
this are replaced by the osg::computeLocalToWorld/WorldToLocal() functions
found in osg/Transform.
Made the ReleaseTextureAndDisplayListsVisitor a public nested class of
osgDB::DatabasePager to allow it to be used in the TXP plugin, and added
usage of this visitor to the TXP plugin to make sure that textures and
display lists are released during the update thread.
leaving it up to the Viewer to specify the mode (which by default is MultiThreaded).
Added a check for the presence of osgParticle systems so that threading is
disabled in this case.
