What is the Blender equivalent of snapping a vacuum cleaner's attachment onto the main hose?

Question

You have the main mesh with a hole of a specific shape. All of the hole's vertices lie on the same plane.

You have a separate mesh (smaller) where one of its protrusions has an open hole, also of the same shape and size as the main mesh's hole, but is NOT co-planar with the main mesh's hole, and its plane isn't even parallel with the main mesh's hole's plane.

I can select both identical loops on both meshes that I wish to merge somehow, but I want the main mesh to stay put, but the smaller mesh to actually move intact into position. Bridging doesn't work because that adds geometry. Merge first/last/center/cursor won't work because those would alter either or both meshes. Merging would move only selected edges, which is not what I want.

The selected loops are identical, just oriented differently. I want to snap-merge the smaller onto the larger mesh. The larger mesh should stay put, but the smaller mesh should move intact.

Answer 1

You can do this with my addon, Mesh Align Plus. GIF below.

• Select 3 verts on your fixed destination (the vacuum cleaner), hit 'Grab Destination'
• Select the corresponding verts on your hose (the thing you want to move) and manually grab (uncheck auto-grab and hit 'Grab Source')
• Select the verts you want to move, and hit apply to: "Mesh Piece" (make sure 'Enable Experimental' is checked, this warns you about non-uniform scaling...apply it if you have non-uniform scaling on your object).

The selection order is very important (it is used to orient the mesh during the transformation), so make sure the corresponding verts are selected in the same order. Your targets don't need to both be within the same mesh, also (object->object, mesh->object etc. are also possible, but slightly different)

It would probably be best to describe this as a 'mate' operation, or plane/face alignment...