Hi Mark, there isn't any built in way to detect duplicate surfaces and unfortunately it's not something that's really feasible for a script to do on its own since it would involve some low level access to the surfaces which is not currently exposed to script.

So the main method to do it will be to select a surface, delete it and see if there is another one underneath it. If there is then you just removed a duplicate. If not then do an undo and you can then hide that surface which you know is a single one to get it out of the way.

Of course it is by far better to not make such duplicates in the first place and also another thing that can help is to not keep your entire model as a bunch of individual surfaces for too long, try to join pieces together where they touch so that you have larger structures, those will be generally easier to manage in things like this. You can break things down into individual surfaces for some time while doing some particular kinds of work but then rejoin them before going onto the next stage of work.


> The other thing I am missing is the ability to limit selection to certain kinds
> of object: surfaces or edges.

There is a new filter mechanism in v3 which can do this - hold down Ctrl and click on the selection dot area of any scene browser item (it's on the far right side of the item) and a filter icon will appear there - while that filter is active it will limit any new selections to only that category of things (note already existing selections are not modified, so you may need to clear the selection before that which is a MoI working habit that it sounds like you have not gotten used to yet). You can find categories for edges or surfaces under the "Types" section of the scene browser and you can also use the same thing under other sections like the style section to limit selection to only objects of a certain style as well. When you are done with the filter push Escape once to clear the current filter.

You can also set multiple filters active at the same time, so for instance setting a filter on Types > Curves as well as Styles > Red at the same time will limit new selections (either by mouse clicking or by actions like select all) to only red curves.


- Michael