Add CanSpawn to ParticleEffect for runtime control over particles spawning

Source/Engine/Particles/ParticleEffect.h

@@ -192,6 +192,12 @@ public:
     API_FIELD(Attributes="NoSerialize, HideInEditor")
     ScriptingObjectReference<SceneRenderTask> CustomViewRenderTask;
 
+    /// <summary>
+    /// Toggles particles spawning functionality (for all emitters) at runtime.
+    /// </summary>
+    API_FIELD(Attributes="NoSerialize, HideInEditor")
+    bool CanSpawn = true;
+
 public:
     /// <summary>
     /// The particles simulation update mode. Defines how to update particles emitter.

Source/Engine/Particles/Particles.cpp

@@ -1702,7 +1702,7 @@ void ParticlesSystem::Job(int32 index)
         // Calculate new time position
         const float startTime = (float)track.AsEmitter.StartFrame / fps;
         const float durationTime = (float)track.AsEmitter.DurationFrames / fps;
-        const bool canSpawn = startTime <= instance.Time && instance.Time <= startTime + durationTime;
+        const bool canSpawn = startTime <= instance.Time && instance.Time <= startTime + durationTime && effect->CanSpawn;
 
         // Update instance data
         data.Sync(effect->Instance, particleSystem, track.AsEmitter.Index);