Initial commit

Assets/Procedural Worlds/Gaia/Scripts/SpawningSystem/TreeManager.cs

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+using UnityEngine;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Gaia
+{
+    /// <summary>
+    /// A class to manage tree instances on unity terrain
+    /// </summary>
+    public class TreeManager
+    {
+        #pragma warning disable 414
+        private List<TreePrototype> m_terrainTrees = new List<TreePrototype>();
+        private Quadtree<int> m_terrainTreeLocations = new Quadtree<int>(new Rect(0,0, 10f, 10f));
+        #pragma warning restore 414
+
+        /// <summary>
+        /// Load the trees in from the terrain
+        /// </summary>
+        public void LoadTreesFromTerrain()
+        {
+            //Destroy previous contents
+            m_terrainTrees = null;
+            m_terrainTreeLocations = null;
+
+            //Work out the bounds of the environment
+            float minY = float.NaN;
+            float minX = float.NaN;
+            float maxX = float.NaN;
+            float minZ = float.NaN;
+            float maxZ = float.NaN;
+            Terrain sampleTerrain = null;
+            foreach (Terrain terrain in Terrain.activeTerrains)
+            {
+                if (float.IsNaN(minY))
+                {
+                    sampleTerrain = terrain;
+                    minY = terrain.transform.position.y;
+                    minX = terrain.transform.position.x;
+                    minZ = terrain.transform.position.z;
+                    maxX = minX + terrain.terrainData.size.x;
+                    maxZ = minZ + terrain.terrainData.size.z;
+                }
+                else
+                {
+                    if (terrain.transform.position.x < minX)
+                    {
+                        minX = terrain.transform.position.x;
+                    }
+                    if (terrain.transform.position.z < minZ)
+                    {
+                        minZ = terrain.transform.position.z;
+                    }
+                    if ((terrain.transform.position.x + terrain.terrainData.size.x) > maxX)
+                    {
+                        maxX = terrain.transform.position.x + terrain.terrainData.size.x;
+                    }
+                    if ((terrain.transform.position.z + terrain.terrainData.size.z) > maxZ)
+                    {
+                        maxZ = terrain.transform.position.z + terrain.terrainData.size.z;
+                    }
+                }
+            }
+
+            if (sampleTerrain != null)
+            {
+                Rect terrainBounds = new Rect(minX, minZ, maxX - minX, maxZ - minZ);
+
+                m_terrainTreeLocations = new Quadtree<int>(terrainBounds, 32);
+                m_terrainTrees = new List<TreePrototype>(sampleTerrain.terrainData.treePrototypes);
+
+                foreach (Terrain terrain in Terrain.activeTerrains)
+                {
+                    float terrainOffsetX = terrain.transform.position.x;
+                    float terrainOffsetZ = terrain.transform.position.z;
+                    float terrainWidth = terrain.terrainData.size.x;
+                    float terrainDepth = terrain.terrainData.size.z;
+                    TreeInstance[] terrainTreeInstances = terrain.terrainData.treeInstances;
+                    for (int treeIdx = 0; treeIdx < terrainTreeInstances.Length; treeIdx++)
+                    {
+                        TreeInstance treeInstance = terrainTreeInstances[treeIdx];
+                        m_terrainTreeLocations.Insert(terrainOffsetX + (treeInstance.position.x * terrainWidth), terrainOffsetZ + (treeInstance.position.z * terrainDepth), terrainTreeInstances[treeIdx].prototypeIndex);
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// Add a tree instance into storage - must be called after the initial load call
+        /// </summary>
+        /// <param name="position"></param>
+        /// <param name="prototypeIdx"></param>
+        public void AddTree(Vector3 position, int prototypeIdx)
+        {
+            if (m_terrainTreeLocations == null)
+            {
+                return;
+            }
+            m_terrainTreeLocations.Insert(position.x, position.z, prototypeIdx);
+        }
+
+        /// <summary>
+        /// Return the number of trees within range of the location provided
+        /// </summary>
+        /// <param name="position">Location to check</param>
+        /// <param name="range">Range around location to check</param>
+        /// <returns>Number of trees within range</returns>
+        public int Count(Vector3 position, float range)
+        {
+            if (m_terrainTreeLocations == null)
+            {
+                return 0;
+            }
+            Rect query = new Rect(position.x - range, position.z - range, range * 2f, range * 2f);
+            return m_terrainTreeLocations.Find(query).Count();
+        }
+
+        /// <summary>
+        /// Return the number of trees being managed
+        /// </summary>
+        /// <returns>Number of trees being managed</returns>
+        public int Count()
+        {
+            if (m_terrainTreeLocations == null)
+            {
+                return 0;
+            }
+            return m_terrainTreeLocations.Count;
+        }
+    }
+}
+