Mesh Combiner Tool is a Unity Editor extension that lets you merge meshes (and their children) into a single optimized mesh at editor time. It is useful for reducing draw calls and improving performance.

Features

• Combine Multiple Meshes Merge selected GameObjects (including all children) into one mesh with a single MeshFilter & MeshRenderer.
• Back-Face Stripping Optionally remove inward-facing triangles to cut away hidden geometry.
• Mutual-Face Culling Cull pairs of nearly opposite faces within a configurable distance threshold to eliminate internal geometry overlaps.
• Hierarchy Preservation & Restoration Captures each object’s parent, sibling index, and local transform so you can “Uncombine” and restore your exact original hierarchy, transforms, and activation states.
• Collider Copying Retains colliders on the combined mesh by duplicating the original GameObjects colliders.
• Tag & Layer Unification If all sources share the same tag or layer, the combined mesh inherits it automatically.
• Undo Support Full integration with Unity’s Undo system for all operations.

Installation

1. Via Git URL (Package Manager)

   • Open Unity’s Window → Package Manager

   • Click the + button → Add package from git URL…

   • Enter:

     https://github.com/Stefaaan06/Unity-Mesh-Combiner.git
     

2. You can now open the tool window under tools -> Mesh Combiner.

Usage

1. In the Unity Editor, select one or more GameObjects (any of them may have children with MeshFilters).

2. Go to Tools → Mesh Combiner to open the combiner window.

3. Toggle options as desired:

4. • Strip inward-facing triangles
   • Cull mutually facing triangles (and adjust the Pair distance threshold)

5. Click Combine Selected

6. • Selected meshes are hidden under an _oldMesh group
   • A new _combined GameObject is created, with combined geometry, materials, tags, layers, and colliders

7. To revert, select the combined GameObject in the Hierarchy and click Uncombine

   • Restores original meshes, hierarchy, transforms, and deletes the combined object

Contribution & Known Issues

Any contribution is welcome as there is still a lot to improve and add:

• Better readme with more images or gifs
• Better workflow for editing merged meshes. Right now you have to Uncombine -> edit the objects -> Combine again
• More and better optimisation methods
• The duplicated colliders dont mirror tags and layers so they have to be set manually
• Merged Objects have all the Materials of the old Meshes, even if they are duplicate. This leads to performance and lighting issues