From Farshid Lashkari, "The following patch adds a multisample option to the

osg::DisplaySettings class. OsgCameraGroup will now read the setting
from the DisplaySettings instead of hardcoding the value. I added the
following commandline option to be able to set the multisample value:

--samples <num>

One thing to note, OsgCameraGroup would previously check if the
computer is an SGI and set multisample to 4. I retained this check in
DisplaySettings to be backwards compatible."

include/osg/DisplaySettings

@@ -171,6 +171,9 @@ class OSG_EXPORT DisplaySettings : public osg::Referenced
         void setMaxNumberOfGraphicsContexts(unsigned int num) { _maxNumOfGraphicsContexts = num; }
         unsigned int getMaxNumberOfGraphicsContexts() const { return _maxNumOfGraphicsContexts; }
 
+        void setNumMultiSamples(unsigned int samples) { _numMultiSamples = samples; }
+        unsigned int getNumMultiSamples() const { return _numMultiSamples; }
+        bool getMultiSamples() const { return _numMultiSamples!=0; }
 
     protected:
     
@@ -202,6 +205,8 @@ class OSG_EXPORT DisplaySettings : public osg::Referenced
         unsigned int                    _minimumNumberAccumAlphaBits;
 
         unsigned int                    _maxNumOfGraphicsContexts;
+        
+        unsigned int                    _numMultiSamples;
 
 };