Update the MissionController line model to a much faster and less expensive implementation

src/MissionManager/MissionController.cc

@@ -608,13 +608,98 @@ void MissionController::_recalcWaypointLines(void)
 
     if (!homeItem) {
         qWarning() << "Home item is not SimpleMissionItem";
+    } else {
+        connect(homeItem, &VisualMissionItem::coordinateChanged, this, &MissionController::_recalcAltitudeRangeBearing);
     }
 
     bool    showHomePosition =  homeItem->showHomePosition();
-    double  homeAlt =           homeItem->coordinate().altitude();
 
     qCDebug(MissionControllerLog) << "_recalcWaypointLines";
 
+    CoordVectHashTable old_table = _lines_table;
+    _lines_table.clear();
+    _waypointLines.clear();
+
+    bool linkBackToHome = false;
+    for (int i=1; i<_visualItems->count(); i++) {
+        VisualMissionItem* item = qobject_cast<VisualMissionItem*>(_visualItems->get(i));
+
+
+        // If we still haven't found the first coordinate item and we hit a a takeoff command link back to home
+        if (firstCoordinateItem &&
+                item->isSimpleItem() &&
+                qobject_cast<SimpleMissionItem*>(item)->command() == MavlinkQmlSingleton::MAV_CMD_NAV_TAKEOFF) {
+            linkBackToHome = true;
+        }
+
+        if (item->specifiesCoordinate()) {
+            if (!item->isStandaloneCoordinate()) {
+                firstCoordinateItem = false;
+                VisualItemPair pair(lastCoordinateItem, item);
+                if (lastCoordinateItem != homeItem || (showHomePosition && linkBackToHome)) {
+                    if (old_table.contains(pair)) {
+                        // Do nothing, this segment already exists and is wired up
+                        _lines_table[pair] = old_table.take(pair);
+                    } else {
+                        // Create a new segment and wire update notifiers
+                        auto linevect       = new CoordinateVector(lastCoordinateItem->isSimpleItem() ? lastCoordinateItem->coordinate() : lastCoordinateItem->exitCoordinate(), item->coordinate(), this);
+                        auto originNotifier = lastCoordinateItem->isSimpleItem() ? &VisualMissionItem::coordinateChanged : &VisualMissionItem::exitCoordinateChanged,
+                             endNotifier    = &VisualMissionItem::coordinateChanged;
+                        // Use signals/slots to update the coordinate endpoints
+                        connect(lastCoordinateItem, originNotifier, linevect, &CoordinateVector::setCoordinate1);
+                        connect(item,               endNotifier,    linevect, &CoordinateVector::setCoordinate2);
+
+                        // FIXME: We should ideally have signals for 2D position change, alt change, and 3D position change
+                        // Not optimal, but still pretty fast, do a full update of range/bearing/altitudes
+                        connect(item, &VisualMissionItem::coordinateChanged, this, &MissionController::_recalcAltitudeRangeBearing);
+                        _lines_table[pair] = linevect;
+                    }
+                }
+                lastCoordinateItem = item;
+            }
+        }
+    }
+
+
+    {
+        // Create a temporary QObjectList and replace the model data
+        QObjectList objs;
+        objs.reserve(_lines_table.count());
+        foreach(CoordinateVector *vect, _lines_table.values()) {
+            objs.append(vect);
+        }
+
+        // We don't delete here because many links may still be valid
+        _waypointLines.swapObjectList(objs);
+    }
+
+
+    // Anything left in the old table is an obsolete line object that can go
+    qDeleteAll(old_table);
+
+    _recalcAltitudeRangeBearing();
+
+    emit waypointLinesChanged();
+}
+
+void MissionController::_recalcAltitudeRangeBearing()
+{
+    if (!_visualItems->count())
+        return;
+
+    bool                firstCoordinateItem =   true;
+    VisualMissionItem*  lastCoordinateItem =    qobject_cast<VisualMissionItem*>(_visualItems->get(0));
+
+    SimpleMissionItem*  homeItem = qobject_cast<SimpleMissionItem*>(lastCoordinateItem);
+
+    if (!homeItem) {
+        qWarning() << "Home item is not SimpleMissionItem";
+    }
+
+    bool    showHomePosition =  homeItem->showHomePosition();
+
+    qCDebug(MissionControllerLog) << "_recalcAltitudeRangeBearing";
+
     // If home position is valid we can calculate distances between all waypoints.
     // If home position is not valid we can only calculate distances between waypoints which are
     // both relative altitude.
@@ -626,11 +711,9 @@ void MissionController::_recalcWaypointLines(void)
 
     double minAltSeen = 0.0;
     double maxAltSeen = 0.0;
-    double homePositionAltitude = homeItem->coordinate().altitude();
+    const double homePositionAltitude = homeItem->coordinate().altitude();
     minAltSeen = maxAltSeen = homeItem->coordinate().altitude();
 
-    _waypointLines.clearAndDeleteContents();
-
     bool linkBackToHome = false;
     for (int i=1; i<_visualItems->count(); i++) {
         VisualMissionItem* item = qobject_cast<VisualMissionItem*>(_visualItems->get(i));
@@ -672,11 +755,10 @@ void MissionController::_recalcWaypointLines(void)
 
                     // Subsequent coordinate items link to last coordinate item. If the last coordinate item
                     // is an invalid home position we skip the line
-                    _calcPrevWaypointValues(homeAlt, item, lastCoordinateItem, &azimuth, &distance, &altDifference);
+                    _calcPrevWaypointValues(homePositionAltitude, item, lastCoordinateItem, &azimuth, &distance, &altDifference);
                     item->setAltDifference(altDifference);
                     item->setAzimuth(azimuth);
                     item->setDistance(distance);
-                    _waypointLines.append(new CoordinateVector(lastCoordinateItem->isSimpleItem() ? lastCoordinateItem->coordinate() : lastCoordinateItem->exitCoordinate(), item->coordinate()));
                 }
                 lastCoordinateItem = item;
             }
@@ -700,8 +782,6 @@ void MissionController::_recalcWaypointLines(void)
             }
         }
     }
-
-    emit waypointLinesChanged();
 }
 
 // This will update the sequence numbers to be sequential starting from 0
@@ -822,7 +902,6 @@ void MissionController::_initVisualItem(VisualMissionItem* visualItem)
 {
     _visualItems->setDirty(false);
 
-    connect(visualItem, &VisualMissionItem::coordinateChanged,                          this, &MissionController::_itemCoordinateChanged);
     connect(visualItem, &VisualMissionItem::specifiesCoordinateChanged,                 this, &MissionController::_recalcWaypointLines);
     connect(visualItem, &VisualMissionItem::coordinateHasRelativeAltitudeChanged,       this, &MissionController::_recalcWaypointLines);
     connect(visualItem, &VisualMissionItem::exitCoordinateHasRelativeAltitudeChanged,   this, &MissionController::_recalcWaypointLines);
@@ -848,12 +927,6 @@ void MissionController::_deinitVisualItem(VisualMissionItem* visualItem)
     disconnect(visualItem, 0, 0, 0);
 }
 
-void MissionController::_itemCoordinateChanged(const QGeoCoordinate& coordinate)
-{
-    Q_UNUSED(coordinate);
-    _recalcWaypointLines();
-}
-
 void MissionController::_itemCommandChanged(void)
 {
     _recalcChildItems();

src/MissionManager/MissionController.h

@@ -12,6 +12,7 @@
 #define MissionController_H
 
 #include <QObject>
+#include <QHash>
 
 #include "QmlObjectListModel.h"
 #include "Vehicle.h"
@@ -19,8 +20,12 @@
 #include "MavlinkQmlSingleton.h"
 #include "VisualMissionItem.h"
 
+class CoordinateVector;
+
 Q_DECLARE_LOGGING_CATEGORY(MissionControllerLog)
 
+typedef QPair<VisualMissionItem*,VisualMissionItem*> VisualItemPair;
+typedef QHash<VisualItemPair, CoordinateVector*> CoordVectHashTable;
 class MissionController : public QObject
 {
     Q_OBJECT
@@ -77,7 +82,6 @@ signals:
 
 private slots:
     void _newMissionItemsAvailableFromVehicle();
-    void _itemCoordinateChanged(const QGeoCoordinate& coordinate);
     void _itemCommandChanged(void);
     void _activeVehicleChanged(Vehicle* activeVehicle);
     void _activeVehicleHomePositionAvailableChanged(bool homePositionAvailable);
@@ -86,6 +90,7 @@ private slots:
     void _inProgressChanged(bool inProgress);
     void _currentMissionItemChanged(int sequenceNumber);
     void _recalcWaypointLines(void);
+    void _recalcAltitudeRangeBearing();
 
 private:
     void _recalcSequence(void);
@@ -97,7 +102,7 @@ private:
     void _deinitVisualItem(VisualMissionItem* item);
     void _autoSyncSend(void);
     void _setupActiveVehicle(Vehicle* activeVehicle, bool forceLoadFromVehicle);
-    void _calcPrevWaypointValues(double homeAlt, VisualMissionItem* currentItem, VisualMissionItem* prevItem, double* azimuth, double* distance, double* altDifference);
+    static void _calcPrevWaypointValues(double homeAlt, VisualMissionItem* currentItem, VisualMissionItem* prevItem, double* azimuth, double* distance, double* altDifference);
     bool _findLastAltitude(double* lastAltitude);
     bool _findLastAcceptanceRadius(double* lastAcceptanceRadius);
     void _addPlannedHomePosition(QmlObjectListModel* visualItems, bool addToCenter);
@@ -112,6 +117,7 @@ private:
     QmlObjectListModel* _visualItems;
     QmlObjectListModel* _complexItems;
     QmlObjectListModel  _waypointLines;
+    CoordVectHashTable  _lines_table;
     Vehicle*            _activeVehicle;
     bool                _autoSync;
     bool                _firstItemsFromVehicle;