The modification consists only in including osgGA::GUIEventAdapter::DOUBLECLICK in the list of "pointerEvent" events.
Test done to reproduce the problem and check the fix: in any osg application or example with an HandleInput function, break on events with a double-click event type. Without the changes, the event's buttonMask does not contain the double-clicked button. With the changes, it does.
Only simple tests (running some examples and playing with the mouse) were done to check that the changes do not break anything, since double-click is not used thoroughly in OSG.
Modification done against current SVN Trunk version (r10753).
As this is a fix, I do not wish to keep my copyright on this submission and assign it over to the project lead.
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