Pause ParticleEmitter when not in use (#1284)

* Pause ParticleEmitter when not in use

* Use timer instead to pause particle system

resources/qml/TimelineView.qml

@@ -25,6 +25,7 @@ Item {
     property var room: null
     property var roomPreview: null
     property bool showBackButton: false
+    property bool shouldEffectsRun: false
     clip: true
 
     onRoomChanged: if (room != null) room.triggerSpecialEffects()
@@ -344,7 +345,10 @@ Item {
         onClicked: Rooms.resetCurrentRoom()
     }
 
-    ParticleSystem { id: confettiParticleSystem }
+    ParticleSystem { id: confettiParticleSystem 
+        Component.onCompleted: pause();
+        paused: !shouldEffectsRun
+    }
 
     Emitter {
         id: confettiEmitter
@@ -356,6 +360,7 @@ Item {
         emitRate: Math.min(400 * Math.sqrt(parent.width * parent.height) / 870, 1000)
         lifeSpan: 15000
         system: confettiParticleSystem
+        maximumEmitted: 500
         velocityFromMovement: 8
         size: 16
         sizeVariation: 4
@@ -365,6 +370,7 @@ Item {
             xVariation: Math.min(4 * parent.width / 7, 450)
             yVariation: 250
         }
+    }
 
     ImageParticle {
         system: confettiParticleSystem
@@ -387,7 +393,6 @@ Item {
             yVariation: 0.2
         }
     }
-    }
 
     Gravity {
         system: confettiParticleSystem
@@ -401,6 +406,14 @@ Item {
         roomid: room ? room.roomId : ""
     }
 
+    Timer {
+        id: effectsTimer
+        onTriggered: shouldEffectsRun = false;
+        interval: confettiEmitter.lifeSpan
+        repeat: false
+        running: false
+    }
+
     Connections {
         function onOpenReadReceiptsDialog(rr) {
             var dialog = readReceiptsDialog.createObject(timelineRoot, {
@@ -424,10 +437,19 @@ Item {
             if (!Settings.fancyEffects)
                 return
 
+            shouldEffectsRun = true;
             confettiEmitter.pulse(parent.height * 2)
             room.markSpecialEffectsDone()
         }
 
+        function onConfettiDone()
+        {
+            if (!Settings.fancyEffects)
+                return
+
+            effectsTimer.start();
+        }
+
         target: room
     }
 

src/timeline/TimelineModel.cpp

@@ -1998,6 +1998,7 @@ void
 TimelineModel::markSpecialEffectsDone()
 {
     needsSpecialEffects_ = false;
+    emit confettiDone();
 }
 
 QString

src/timeline/TimelineModel.h

@@ -451,6 +451,7 @@ signals:
     void newCallEvent(const mtx::events::collections::TimelineEvents &event);
     void scrollToIndex(int index);
     void confetti();
+    void confettiDone();
 
     void lastMessageChanged();
     void notificationsChanged();