Rewrote the osgbillboard demo so that it creates a point rotatated billbaord
and X,Y and Z axis billboards to both test and demonstrate this types of
billboards in action.
is orientated towards the viewer.
Changed the lightmodel ambient level to 0.1,0.1,0.1 instead of 0.0, so that
a small amount of ambient lighting is available to render back surfaces.
The osgreflect and osgprerender suffered unexpected behaviors because of
no lighting on the backfaces.
to print out progress and report any memory leaks which have been logged.
The later will only occur with a debug build. The use of echo and more
makes this version osgtest.bat not portable to windows unfortuntately.
