EarthManip: another tweak to the tether chasing code

gwaldron · Feb 2, 2015 · 00a5bd6 · 00a5bd6
1 parent b965a4f
commit 00a5bd6
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Showing 2 changed files with 15 additions and 10 deletions.
diff --git a/src/osgEarthUtil/EarthManipulator b/src/osgEarthUtil/EarthManipulator
@@ -898,7 +898,8 @@ namespace osgEarth { namespace Util
         bool _is_geocentric;
         bool _srs_lookup_failed;
 
-        osg::observer_ptr<osg::Node> _tether_node;        
+        osg::observer_ptr<osg::Node> _tether_node;     
+        bool                         _tether_completed;
 
         double                  _time_s_last_frame;
         double                  _time_s_now;        
@@ -947,7 +948,7 @@ namespace osgEarth { namespace Util
         double                  _pending_viewpoint_duration_s;
 
         bool                    _setting_viewpoint;
-        bool                    _set_viewpoint_started_while_tethered;
+        //bool                    _set_viewpoint_started_while_tethered;
         Viewpoint               _start_viewpoint;
         double                  _delta_heading, _delta_pitch, _delta_range, _arc_height;
         osg::Vec3d              _delta_focal_point;

diff --git a/src/osgEarthUtil/EarthManipulator.cpp b/src/osgEarthUtil/EarthManipulator.cpp
@@ -837,9 +837,6 @@ EarthManipulator::setViewpoint( const Viewpoint& vp, double duration_s )
             vp.getSRS()->transform( vp.getFocalPoint(), _cached_srs.get(), vpFocalPoint );
         }
 
-        // if we are currently tethered, make a note of it.
-        _set_viewpoint_started_while_tethered = _tether_node.valid();
-
         _start_viewpoint = getViewpoint();
 
         _delta_heading = vp.getHeading() - _start_viewpoint.getHeading(); //TODO: adjust for crossing -180
@@ -991,8 +988,9 @@ EarthManipulator::updateSetViewpoint()
 
     if ( t >= 1.0 )
     {
-        t = tp = 1.0;
+        t = tp = 1.0;        
         _setting_viewpoint = false;
+        _tether_completed = true;
     }
     else if ( _arc_height > 0.0 )
     {
@@ -1072,6 +1070,8 @@ EarthManipulator::getViewpoint() const
 void
 EarthManipulator::setTetherNode( osg::Node* node, double duration_s )
 {
+    _tether_completed = true;
+
     if (_tether_node != node)
     {
         _offset_x = 0.0;
@@ -1103,6 +1103,7 @@ EarthManipulator::setTetherNode( osg::Node* node, double duration_s )
 
     if (_tether_node.valid() && duration_s > 0.0)
     {                
+        _tether_completed = false;
         Viewpoint destVP = getTetherNodeViewpoint();
         setViewpoint( destVP, duration_s );
     }
@@ -1446,9 +1447,12 @@ EarthManipulator::handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapt
             if ( _frame_count < 2 )
                 _time_s_set_viewpoint = _time_s_now;
 
-            // if we're tethered, we need to update the viewpoint in the post-update
-            // phase to pre
-            if ( !_tether_node.valid() || !_set_viewpoint_started_while_tethered )
+            // if we're not tethered, OR if we are tethered and the tethering process
+            // is complete, we can update the camera now. Otherwise we have to update
+            // it in the post-update phase to maintain frame synchronization between
+            // the camera and the tether target.
+            if ((!_tether_node.valid()) ||
+                (_tether_node.valid() && !_tether_completed))
             {
                 updateSetViewpoint();
             }
@@ -1778,7 +1782,7 @@ EarthManipulator::updateTether()
             vp.getSRS()->transform( vp.getFocalPoint(), _cached_srs.get(), vpFocalPoint );
         }
 
-        if ( _set_viewpoint_started_while_tethered )
+        if ( _tether_completed )
         {
             _start_viewpoint.setFocalPoint( vpFocalPoint );
             _delta_focal_point.set(0,0,0);