Added the Blackholio Unreal Blueprint Tutorial (#3313)

# Description of Changes

- Expanded on the Unreal tutorial to create the Blueprint version,
~~this uses :::server-cpp and :::server-blueprint which might not work
yet when deploying~~ with using Docusaurus Tabs.
- Updated the server side code to use signed integers as discussed for
both Rust + C# server modules.

# API and ABI breaking changes

None

# Expected complexity level and risk

1 - Documentation update, does update the server side 

# Testing

- [x] Manually tested both Rust + C# modules
- [x] Ran through all images and steps

Author: JasonAtClockwork

demo/Blackholio/client-unity/Assets/PlayModeTests/PlayModeExampleTest.cs

@@ -89,7 +89,7 @@ public IEnumerator CreatePlayerAndTestDecay()
             Debug.Assert(circle != null, nameof(circle) + " != null");
             var ourEntity = GameManager.Conn.Db.Entity.EntityId.Find(circle.EntityId);
             var toChosenFood = new UnityEngine.Vector2(1000, 0);
-            uint chosenFoodId = 0;
+            int chosenFoodId = 0;
             foreach (var food in GameManager.Conn.Db.Food.Iter())
             {
                 var thisFoodId = food.EntityId;

demo/Blackholio/client-unity/Assets/Scripts/EntityController.cs

@@ -12,14 +12,14 @@ public abstract class EntityController : MonoBehaviour
 
 	private static readonly int ShaderColorProperty = Shader.PropertyToID("_Color");
 
-	[DoNotSerialize] public uint EntityId;
+	[DoNotSerialize] public int EntityId;
 
 	protected float LerpTime;
 	protected Vector3 LerpStartPosition;
 	protected Vector3 LerpTargetPosition;
 	protected Vector3 TargetScale;
 
-	protected virtual void Spawn(uint entityId)
+	protected virtual void Spawn(int entityId)
 	{
 		EntityId = entityId;
 
@@ -82,12 +82,12 @@ public virtual void Update()
 		transform.localScale = Vector3.Lerp(transform.localScale, TargetScale, Time.deltaTime * 8);
 	}
 
-	public static Vector3 MassToScale(uint mass)
+	public static Vector3 MassToScale(int mass)
 	{
 		var diameter = MassToDiameter(mass);
 		return new Vector3(diameter, diameter, 1);
 	}
 
-	public static float MassToRadius(uint mass) => Mathf.Sqrt(mass);
-	public static float MassToDiameter(uint mass) => MassToRadius(mass) * 2;
+	public static float MassToRadius(int mass) => Mathf.Sqrt(mass);
+	public static float MassToDiameter(int mass) => MassToRadius(mass) * 2;
 }

demo/Blackholio/client-unity/Assets/Scripts/GameManager.cs

@@ -24,8 +24,8 @@ public class GameManager : MonoBehaviour
     public static Identity LocalIdentity { get; private set; }
     public static DbConnection Conn { get; private set; }
 
-    public static Dictionary<uint, EntityController> Entities = new Dictionary<uint, EntityController>();
-    public static Dictionary<uint, PlayerController> Players = new Dictionary<uint, PlayerController>();
+    public static Dictionary<int, EntityController> Entities = new Dictionary<int, EntityController>();
+    public static Dictionary<int, PlayerController> Players = new Dictionary<int, PlayerController>();
 
     private void Start()
     {
@@ -102,19 +102,19 @@ private void HandleSubscriptionApplied(SubscriptionEventContext ctx)
     {
         Debug.Log("Subscription applied!");
         OnSubscriptionApplied?.Invoke();
-        
+
         // Once we have the initial subscription sync'd to the client cache
         // Get the world size from the config table and set up the arena
         var worldSize = Conn.Db.Config.Id.Find(0).WorldSize;
         SetupArena(worldSize);
-        
+
         // Check to see if we already have a player, if we don't we'll need to create one
         var player = ctx.Db.Player.Identity.Find(LocalIdentity);
         if (string.IsNullOrEmpty(player.Name))
         {
             // The player has to choose a username
             UIUsernameChooser.Instance.Show(true);
-            
+
             // When our username is updated, hide the username chooser
             Conn.Db.Player.OnUpdate += (_, _, newPlayer) =>
             {
@@ -123,14 +123,18 @@ private void HandleSubscriptionApplied(SubscriptionEventContext ctx)
                     UIUsernameChooser.Instance.Show(false);
                 }
             };
-        } else {
+        }
+        else
+        {
             // We already have a player
             if (ctx.Db.Circle.PlayerId.Filter(player.PlayerId).Any())
             {
                 // We already have at least one circle, we should just be able to start
                 // playing immediately.
                 UIUsernameChooser.Instance.Show(false);
-            } else {
+            }
+            else
+            {
                 // Create a new circle for our player.
                 ctx.Reducers.EnterGame(player.Name);
             }
@@ -209,7 +213,7 @@ private static void PlayerOnDelete(EventContext context, Player deletedvalue)
         }
     }
 
-    private static PlayerController GetOrCreatePlayer(uint playerId)
+    private static PlayerController GetOrCreatePlayer(int playerId)
     {
         if (!Players.TryGetValue(playerId, out var playerController))
         {

demo/Blackholio/client-unity/Assets/Scripts/LeaderboardRow.cs

@@ -8,7 +8,7 @@ public class LeaderboardRow : MonoBehaviour
     public TextMeshProUGUI UsernameText;
     public TextMeshProUGUI MassText;
 
-    public void SetData(string username, uint mass)
+    public void SetData(string username, int mass)
 	{
 		UsernameText.text = username;
 		MassText.text = mass.ToString();

demo/Blackholio/client-unity/Assets/Scripts/PlayerController.cs

@@ -11,7 +11,7 @@ public class PlayerController : MonoBehaviour
 
     public static PlayerController Local { get; private set; }
 
-    private uint PlayerId;
+    private int PlayerId;
     private float LastMovementSendTimestamp;
     private Vector2? LockInputPosition;
     private List<CircleController> OwnedCircles = new List<CircleController>();
@@ -56,9 +56,9 @@ public void OnCircleDeleted(CircleController deletedCircle)
         }
     }
 
-    public uint TotalMass()
+    public int TotalMass()
     {
-        return (uint)OwnedCircles
+        return (int)OwnedCircles
             .Select(circle => GameManager.Conn.Db.Entity.EntityId.Find(circle.EntityId))
             .Sum(e => e?.Mass ?? 0); //If this entity is being deleted on the same frame that we're moving, we can have a null entity here.
     }