New version 1.1
-add calculation for round walls including sloping (thanks to hansmex )
-add support for imperial measurement
-few code modification
Possible errors:
-when You modify walls after room creation even in plan don't appear so
TO DO:
-subtract holes surfaces BUT
there are many situations when will give wrong results
e.g. superimposing doors over frame door or service hatch
-I could add a new column with this calculation or modify the current one or forget
PS: make some test file to verify the accuracy;
If You discover something wrong let me know.
Also on Source Forge