mesh.SetVertexBufferData and mesh.SetIndices calculates bounds incorrectly when mesh.RecalculateBounds is not called

2023.1.X

As Designed

The bound recalculation is done for the submesh, not the mesh. Mesh.SetIndices takes the submesh in as a parameter. The result of the recalculation can be found on the bounds of that submesh; mesh.GetSubMesh(0).bounds in this case. When printing this to the console the expected value is observed. We have a backlog item to smooth out the behavior around mesh bounds and submesh bounds. However, we have other higher priority work at the moment. See also: - https://issuetracker.unity3d.com/issues/bounds-are-not-applied-to-mesh-when-using-mesh-dot-applyanddisposewritablemeshdata - https://docs.unity3d.com/ScriptReference/Rendering.MeshUpdateFlags.DontRecalculateBounds.html