Compute live location bounding box and center the map accordingly

src/models/livelocationsmodel.cpp

@@ -38,6 +38,9 @@ LiveLocationsModel::LiveLocationsModel(QObject *parent)
             });
         },
         Qt::QueuedConnection); // deferred so we are sure the eventId filter is set
+
+    connect(this, &LiveLocationsModel::dataChanged, this, &LiveLocationsModel::boundingBoxChanged);
+    connect(this, &LiveLocationsModel::rowsInserted, this, &LiveLocationsModel::boundingBoxChanged);
 }
 
 int LiveLocationsModel::rowCount(const QModelIndex &parent) const
@@ -101,6 +104,21 @@ QHash<int, QByteArray> LiveLocationsModel::roleNames() const
     return r;
 }
 
+QRectF LiveLocationsModel::boundingBox() const
+{
+    QRectF bbox(QPointF(180.0, 90.0), QPointF(-180.0, -90.0));
+    for (auto i = 0; i < rowCount(); ++i) {
+        const auto lat = data(index(i, 0), LatitudeRole).toDouble();
+        const auto lon = data(index(i, 0), LongitudeRole).toDouble();
+
+        bbox.setLeft(std::min(bbox.left(), lon));
+        bbox.setRight(std::max(bbox.right(), lon));
+        bbox.setTop(std::min(bbox.top(), lat));
+        bbox.setBottom(std::max(bbox.bottom(), lat));
+    }
+    return bbox;
+}
+
 void LiveLocationsModel::addEvent(const Quotient::RoomEvent *event)
 {
     if (event->isStateEvent() && event->matrixType() == "org.matrix.msc3672.beacon_info") {

src/models/livelocationsmodel.h

@@ -8,6 +8,7 @@
 
 #include <QAbstractListModel>
 #include <QPointer>
+#include <QRectF>
 
 namespace Quotient
 {
@@ -36,6 +37,9 @@ class LiveLocationsModel : public QAbstractListModel
      */
     Q_PROPERTY(QString eventId MEMBER m_eventId NOTIFY eventIdChanged)
 
+    /** Bounding box of all live location beacons covered by this model. */
+    Q_PROPERTY(QRectF boundingBox READ boundingBox NOTIFY boundingBoxChanged)
+
 public:
     explicit LiveLocationsModel(QObject *parent = nullptr);
 
@@ -52,9 +56,12 @@ public:
     QVariant data(const QModelIndex &index, int roleName) const override;
     QHash<int, QByteArray> roleNames() const override;
 
+    QRectF boundingBox() const;
+
 Q_SIGNALS:
     void roomChanged();
     void eventIdChanged();
+    void boundingBoxChanged();
 
 private:
     void addEvent(const Quotient::RoomEvent *event);

src/qml/Component/Timeline/LiveLocationDelegate.qml

@@ -34,8 +34,8 @@ TimelineContainer {
             Layout.fillWidth: true
             Layout.preferredHeight: root.contentMaxWidth / 16 * 9
 
-            // center: QtPositioning.coordinate(root.latitude, root.longitude)
-            // zoomLevel: 15
+            center: QtPositioning.coordinate(liveLocationModel.boundingBox.y, liveLocationModel.boundingBox.x)
+            zoomLevel: 15
 
             plugin: OsmLocationPlugin.plugin
             onCopyrightLinkActivated: Qt.openUrlExternally(link)