Hi Peer,

re:
> What are the methods for surface area and volume in the Details of the properties panel?

They use factories to get the built in non-blocking asynchronous updates.

Factory names: calclength, calcarea, calcvolume. Each takes an object list in input index 0 and fills in index 1 with the result value asynchronously. You have to call factory.waitForAsyncUpdate().

- Michael