Divide quad mesh

[aleksanderdynarek]

Hi guys, I am looking for methods to implement quad subdivision in grasshopper C#.

I am working on a mesh growth model, but with very strict limitations to faces size, number of edges, planarity etc. because every face will be a unit in fabrication model. I need methods to split chosen quad faces - to split them in half (in other words, to create two rectangles from one square) or to split a quad in its center to form four quads.

i know MeshTopologyEdgeList.CollapseEdge and SplitEdge methods, but as far as I know they split every quad to triangles. I tried to split two symetrical edges of a chosen face at one ireration time but after every splitting all the topology changes for vertices (meaning: they change indexes) and i dont know how to do that.

anyone knows the way?

[laurent_delrieu]

My way will be to duplicate the mesh and use the old for the topology and the new for storing new vertices and new faces

[aleksanderdynarek]

can you explain in a more detailed way how to do it to split a quad into quads? or maybe show some examples?

[dsonntag]

What would you like to happen with the neighboring quads?

And how do you make the decision on how the rectangles are oriented?

[aleksanderdynarek]

First of all, to start, i would like them to split and grow in one direaction. Like a mesh tube. Naked edges on one side of the tube will grow based on some agent behaviour (agents = naked vertices) and after some length of the quad it will be splitted in two.

[aleksanderdynarek]

can you elaborate how you do it? or show some examples?

[laurent_delrieu]

You could look inside Mesh Iso splitting script

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Look at the sphere script

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As a mesh is vertices and topology you must find a strategy to keep track of that.