⚙ Subclassing simplified, MonoBehaviour dependency removed

- Base quadtree now independent of MonoBehaviour
- Improved generic classes
- Eased subclassing of the tree structures
- Improved and added missing doc-comments

Author: dolejska-daniel

Scripts/GameObjectRootNode.cs

@@ -6,7 +6,7 @@ namespace Quadtree
     /// <inheritdoc cref="RootNode{TItem}"/>
     [ExecuteInEditMode]
     [AddComponentMenu("Spatial partitioning/Quadtree/Root node (for GameObjects)")]
-    public class GameObjectRootNode : RootNode<GameObjectItem>
+    public class GameObjectRootNode : QuadtreeMonoRoot<GameObjectItem>
     {
     }
 }

Scripts/GameObjectRootNode.cs.meta

@@ -0,0 +1,118 @@
+using Quadtree.Items;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace Quadtree
+{
+    /// <summary>
+    /// Mandatory interface of any single quad tree node.
+    /// </summary>
+    public interface INode<TItem, TNode>
+        where TItem : IItem<TItem, TNode>
+        where TNode : INode<TItem, TNode>
+    {
+        /// <summary>
+        /// Bounds of this tree node.
+        /// </summary>
+        Bounds Bounds { get; set; }
+
+        /// <summary>
+        /// Root of the whole tree.
+        /// </summary>
+        IQuadtreeRoot<TItem, TNode> TreeRoot { get; set; }
+
+        /// <summary>
+        /// Reference to parent tree node.
+        /// </summary>
+        /// <remarks>
+        /// Is <c>null</c> for root node of the tree.
+        /// </remarks>
+        TNode ParentNode { get; set; }
+
+        /// <summary>
+        /// Child nodes of this node.
+        /// </summary>
+        IList<TNode> SubNodes { get; set; }
+
+        /// <summary>
+        /// Verifies whether provided boundaries (<paramref name="bounds"/>) are fully contained within the boundaries of the node.
+        /// </summary>
+        /// 
+        /// <param name="bounds">Boundaries of an object</param>
+        /// <returns><c>True</c> if object is fully contained within the node, <c>False</c> otherwise</returns>
+        bool Contains(Bounds bounds);
+
+        /// <summary>
+        /// Calculates relative internal position of the provided bounds (<paramref name="bounds"/>) within the node.
+        /// </summary>
+        /// <remarks>
+        /// The method expects the boundaries to be fully contained within the node.
+        /// </remarks>
+        /// 
+        /// <param name="bounds">Boundaries contained within the node</param>
+        /// <returns>Relative internal position</returns>
+        IntraLocation Location(Bounds bounds);
+
+        /// <summary>
+        /// Inserts item (<paramref name="item"/>) into the smallest node possible in the subtree.
+        /// </summary>
+        /// <remarks>
+        /// The method expects item boundaries to be fully contained within the node.
+        /// </remarks>
+        /// 
+        /// <param name="item">Item to be inserted</param>
+        void Insert(TItem item);
+
+        /// <summary>
+        /// Removes the provided item (<paramref name="item"/>) from the node and its subtree.
+        /// </summary>
+        /// 
+        /// <param name="item">Item to be removed from the tree</param>
+        void Remove(TItem item);
+
+        /// <summary>
+        /// Checks whether the node and recursively all its subnodes are empty.
+        /// </summary>
+        /// 
+        /// <returns><c>True</c> if node and all its subnodes are empty, <c>False</c> otherwise</returns>
+        bool IsEmpty();
+
+        /// <summary>
+        /// Updates provided item's (<paramref name="item"/>) location within the tree.
+        /// </summary>
+        /// 
+        /// <param name="item">Item which's location is to be updated</param>
+        /// <param name="forceInsertionEvaluation"><c>True</c> forces tree to re-insert the item</param>
+        /// <param name="hasOriginallyContainedItem"><c>True</c> only for the first called node</param>
+        void Update(TItem item, bool forceInsertionEvaluation = true, bool hasOriginallyContainedItem = true);
+
+        /// <summary>
+        /// Finds items (<paramref name="items"/>) located within provided boundaries (<paramref name="bounds"/>).
+        /// </summary>
+        /// 
+        /// <param name="bounds">Boundaries to look for items within</param>
+        /// <param name="items">Output list for found items</param>
+        void FindAndAddItems(Bounds bounds, ref IList<TItem> items);
+
+        /// <summary>
+        /// Adds all items of this node and its sub-nodes to the provided list of items (<paramref name="items"/>).
+        /// If boundaries (<paramref name="bounds"/>) are provided then only items intersecting with them will be added.
+        /// </summary>
+        /// 
+        /// <param name="items">Output list for found items</param>
+        /// <param name="bounds">Boundaries to look for items within</param>
+        void AddItems(ref IList<TItem> items, Bounds? bounds = null);
+
+        /// <summary>
+        /// Removes any existing items from the node and removes all of its sub-nodes.
+        /// </summary>
+        void Clear();
+
+        /// <summary>
+        /// Displays boundaries of this node and all its sub-nodes and optinally a current number of contained items if <paramref name="displayNumberOfItems"/> is <c>True</c>.
+        /// </summary>
+        /// 
+        /// <param name="displayNumberOfItems"><c>True</c> if number of node's items should be displayed</param>
+        void DrawBounds(bool displayNumberOfItems = false);
+    }
+}

Scripts/INode.cs

@@ -0,0 +1,70 @@
+using Quadtree.Items;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace Quadtree
+{
+    /// <summary>
+    /// Main class of the Quadtree structure - it represents the root of the tree.
+    /// </summary>
+    public interface IQuadtreeRoot<TItem, TNode>
+        where TItem : IItem<TItem, TNode>
+        where TNode : INode<TItem, TNode>
+    {
+        /// <summary>
+        /// The tree has been initialized and is ready to be used.
+        /// </summary>
+        bool Initialized { get; }
+
+        /// <summary>
+        /// Node currently acting as a root of the tree.
+        /// </summary>
+        TNode CurrentRootNode { get; }
+
+        /// <summary>
+        /// Minimum possible size of any of the nodes.
+        /// </summary>
+        /// <remarks>
+        /// Must always be a positive number or zero for no size limit.
+        /// </remarks>
+        float MinimumPossibleNodeSize { get; }
+
+        /// <summary>
+        /// Determines whether or not should number of items in nodes be displayed in gizmos.
+        /// </summary>
+        bool DisplayNumberOfItemsInGizmos { get; }
+
+        /// <summary>
+        /// Inserts item to the tree structure.
+        /// </summary>
+        /// 
+        /// <param name="item">Item to be inserted</param>
+        void Insert(TItem item);
+
+        /// <summary>
+        /// Expands size of root node.
+        /// New root node is created and current root node is assigned as its sub-node.
+        /// </summary>
+        void Expand();
+
+        /// <summary>
+        /// Finds items located within provided boundaries.
+        /// </summary>
+        /// 
+        /// <param name="bounds">Boundaries to look for items within</param>
+        /// <returns>List of items found within provided boundaries</returns>
+        List<TItem> Find(Bounds bounds);
+
+        /// <summary>
+        /// Removes provided item from the tree.
+        /// </summary>
+        /// 
+        /// <param name="item">Item to be removed from the tree</param>
+        void Remove(TItem item);
+
+        /// <summary>
+        /// Clears and resets the whole tree.
+        /// </summary>
+        void Clear();
+    }
+}

Scripts/RootNode.cs.meta renamed to Scripts/INode.cs.meta

@@ -0,0 +1,22 @@
+
+namespace Quadtree
+{
+    /// <summary>
+    /// Describes relative local position in respect to the current node.
+    /// </summary>
+    /// <remarks>
+    /// Integer values of <c>UPPER_LEFT</c>, <c>UPPER_RIGHT</c>, <c>LOWER_RIGHT</c>, <c>LOWER_LEFT</c> do correspond with the indices of the sub-nodes.
+    /// </remarks>
+    public enum IntraLocation
+    {
+        UPPER_LEFT,
+        UPPER_RIGHT,
+        LOWER_RIGHT,
+        LOWER_LEFT,
+        SPANNING_LEFT,
+        SPANNING_RIGHT,
+        SPANNING_UPPER,
+        SPANNING_LOWER,
+        SPANNING
+    };
+}