Replace and Copy Mesh Commands are expensive for large meshes or long sessions #78
Description
Stores a copy of the entire mesh in memory for every edit. These all add up as they are stored for the entire session.
Edits could be expressed in a much more compressed form (either a delta or as a procedural instruction for how to change the mesh)
CopyMesh has a similar problem but in some ways it is even more wasteful. The only time the stored mesh is needed is on "redo" and at that point in time the mesh always in the scene. A copy command could "redo" just by referencing the already existing mesh.