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Detail asset from Unity Asset Store: https://assetstore.unity.com/packages/tools/utilities/simple-mesh-combine-8748
But now you can download Simple Mesh Combine FREE.
Simple Mesh Combine v1.71
One click mesh combine tool
Easily combine meshes by attaching this script to a GameObject containing meshes with the same material.
Click the Combine button to merge meshes.
To decombine just click the Release button.
Easily decrease draw calls to improve game performance.
Added Export to OBJ (Beta)
Added Copy Colliders function
Easily create new prefabs with combined mesh
Added optional C# script
Added Multiple material support
Added Lightmap support (optional)
Added Save Mesh to project folder
Combined mesh is limited to the Unity standard 65536 vertices.
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