use a constantly seeded random stream for idle movements, for cluster-robustness.

Source/CharacterPlugin/Private/VirtualHuman.cpp

@@ -37,6 +37,10 @@ void AVirtualHuman::BeginPlay()
 	SetUpBodyType();
 
 	bFirstTick = true;
+
+	// constantly seed the random stream so we don't have cluster syncing problems
+	// but seed it with the name of the VH, so random behavior is different for every VH
+	IdleRandomStream = FRandomStream(TextKeyUtil::HashString(*GetOwner()->GetName()));
 }
 
 // Called every frame
@@ -292,7 +296,7 @@ void AVirtualHuman::PlayRandomIdleAnimation()
 	}
 
 	// play arandom idle animation
-	int Random = FMath::RandRange(0, CustomIdleAnimations.Num() - 1);
+	int Random = IdleRandomStream.RandRange(0, CustomIdleAnimations.Num() - 1);
 	UAnimSequence* IdleAnim = CustomIdleAnimations[Random];
 	if (IdleAnim)
 	{

Source/CharacterPlugin/Public/VirtualHuman.h

@@ -135,6 +135,7 @@ private:
 	void PlayRandomIdleAnimation();
 	UPROPERTY()
 	FTimerHandle NextIdleTimerHandle;
+	FRandomStream IdleRandomStream;
 
 #if WITH_EDITOR
 	virtual void PostEditChangeProperty(FPropertyChangedEvent& PropertyChangedEvent) override;