Add script for combining children meshes

Author: adamgraham

Runtime/CombineChildrenMeshes.cs

@@ -0,0 +1,96 @@
+using UnityEngine;
+
+namespace Zigurous.Graphics
+{
+    /// <summary>
+    /// Combines the meshes of the children of the game object into one mesh.
+    /// </summary>
+    [RequireComponent(typeof(MeshFilter))]
+    [AddComponentMenu("Zigurous/Graphics/Combine Children Meshes")]
+    public sealed class CombineChildrenMeshes : MonoBehaviour
+    {
+        /// <summary>
+        /// Combines the mesh on start, otherwise it needs to be called manually.
+        /// </summary>
+        [Tooltip("Combines the mesh on start, otherwise it needs to be called manually.")]
+        public bool combineOnStart = true;
+
+        /// <summary>
+        /// Removes the child meshes from the game object after combining.
+        /// </summary>
+        [Tooltip("Removes the child meshes from the game object after combining.")]
+        public bool removeChildMeshes = true;
+
+        /// <summary>
+        /// Optimizes the combined mesh data to improve rendering performance.
+        /// </summary>
+        [Tooltip("Optimizes the combined mesh data to improve rendering performance.")]
+        public bool optimizeMesh = true;
+
+        /// <summary>
+        /// Recalculates the bounding volume of the combined mesh.
+        /// </summary>
+        [Tooltip("Recalculates the bounding volume of the combined mesh.")]
+        public bool recalculateBounds = true;
+
+        private void Start()
+        {
+            MeshFilter parent = GetComponent<MeshFilter>();
+
+            if (this.combineOnStart && parent != null) {
+                parent.mesh = Combine();
+            }
+        }
+
+        /// <summary>
+        /// Combines the meshes of the children of this game object.
+        /// </summary>
+        /// <returns>A new combined mesh.</returns>
+        public Mesh Combine()
+        {
+            MeshFilter[] children = GetComponentsInChildren<MeshFilter>();
+            CombineInstance[] combine = new CombineInstance[children.Length - 1];
+
+            int submesh = 0;
+
+            for (int i = 0; i < children.Length; i++)
+            {
+                MeshFilter child = children[i];
+
+                // Ignore the parent mesh
+                if (child.transform == this.transform) {
+                    continue;
+                }
+
+                // Create a mesh combine instance
+                CombineInstance instance = new CombineInstance();
+                instance.mesh = child.mesh;
+                instance.transform = Matrix4x4.TRS(child.transform.localPosition, child.transform.localRotation, child.transform.localScale);
+                combine[submesh++] = instance;
+
+                // Destroy the child mesh
+                if (this.removeChildMeshes)
+                {
+                    Destroy(child.GetComponent<MeshRenderer>());
+                    Destroy(child);
+                }
+            }
+
+            // Create a new mesh from all of the combined children
+            Mesh combinedMesh = new Mesh();
+            combinedMesh.CombineMeshes(combine);
+
+            if (this.optimizeMesh) {
+                combinedMesh.Optimize();
+            }
+
+            if (this.recalculateBounds) {
+                combinedMesh.RecalculateBounds();
+            }
+
+            return combinedMesh;
+        }
+
+    }
+
+}

Runtime/CombineChildrenMeshes.cs.meta

@@ -20,9 +20,9 @@ public sealed class SaveMesh : MonoBehaviour
         public string assetName;
 
         /// <summary>
-        /// Saves the mesh on start, otherwise it needs to be saved manually.
+        /// Saves the mesh on start, otherwise it needs to be called manually.
         /// </summary>
-        [Tooltip("Saves the mesh on start, otherwise it needs to be saved manually.")]
+        [Tooltip("Saves the mesh on start, otherwise it needs to be called manually.")]
         public bool saveOnStart = true;
 
         private void Reset()