Merge non-planar faces

Hi there,

I have a question.
When I soothe/tidy breps I usually use MergeAllCoplanarFaces.
This is supercool and I use it on a daily basis.

Now I have a case where I have surfaces that have 1 curvature. I guess they could be merged, right?
Is there an easy way to achieve that or would that be manual work for each situation?


Hi Tobias -

We have that feature request on the list → RH-10693 MergeAllFaces work on degree 2 surfaces

Also see this thread for a script:


Hi @wim,

thanks a lot.
I will give it a try.

I do not mean to offend, but I think this feature is not soon gonna be implemented, right?

Not for V8 as far as I know. If we’re lucky, it might make it into the V9 WIP…

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MergeSrf with Smooth=No for degree 1 and degree 2 surfaces will create a single degree 2 surface and not change the shape. Needs to be executed for each pair of adjacent edges. Or use the script in the link above (which I have not tested).

MergeAllFaces creates a new planar surface with the same border as the coplanar faces it replaces. This is a simple to do and has no restrictions on the individual faces having trimmed edges. The result can have exactly the same border as the input.

In contrast merging non-planar surfaces is more complex and in general restricted to only merging where the edges/seams of the individual faces are untrimmed. For MergeAllFaces to work on non-planar surfaces a fundamentally different algorithm/code would be needed, similar to that used by MergeSrf, and then it would be restricted to only merging when the internal seams/edges are untrimmed.

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