These Components are now a part of Pufferfish and will be updated there from now on.
Download and install Pufferfish to get them: http://www.food4rhino.com/app/pufferfish
A component inspired by Autodesk Maya's Mirror Cut tool, which is great for creating symmetry. Mirror cut trims a mesh at a plane then mirrors it over the plane and stitches the original + mirrored meshes together into one new clean mesh. It is really handy to run in a loop with Anemone for generating many variations of a geometry, essentially creating a sort of library of parts. Also, by compounding multiple iterations of mirror cut onto one geometry you quickly get some complex shapes emerging from simple ones. The component works with opened and closed meshes. Will appear in the Mesh > Util tab.
Mesh Mirror Cut(MMCut): Mirror a mesh across a plane and merge it with the original.
Input M: Mesh - Mesh to mirror cut
Input P: Plane - Mirror cut plane
Input T: Threshold - Vertices within this distance of the mirror plane will be culled
Input S: Shrink - Shrink quads, if true, quads removed by the mirror plane will become triangles if possible
Input I: Insert - Insert loop, if true, an edge loop will be added where the mirror cut plane intersects the mesh
Output M: Mesh - Mirror cut mesh
Grasshopper for Rhino 6 for Win
Grasshopper for Rhino 5 Mac