SUM a dynamic range not including hidden cells

A combination of UDF and worksheet events given .Have a trail.
code for UDF

Function SumVisibleClms(SumRng As Range) As Double

Application.Volatile
Dim cel As Range

For Each cel In SumRng
If cel.EntireColumn.Hidden = False Then SumVisibleClms = SumVisibleClms + cel.Value
Next cel

End Function