| index | The index of the sub-mesh to set data for. See subMeshCount. If you specify an out of range index, Unity throws an exception. |
| desc | Sub-mesh data. |
| flags | Flags controlling the function behavior. See MeshUpdateFlags. |
Sets the data for a sub-mesh of the Mesh that Unity creates from the MeshData.
See Mesh.SetSubMesh for more information on setting sub-mesh data.
If you call this method on a read-only MeshData, Unity throws an exception.