Custom data of vertices, Vertex Layers

Question

I found this answer (first answer) Python: assign custom tag to vertices

I'm pretty excited of this. But I have some questions:

1) How to get all vertices which have 'my_id' custom data?

2) How to remove 'my_id' custom data from all vertices. To clear vertices from unnecessary custom data.

Thanks.

Answer 1

1)

 [i for i in bm.verts if i[my_id]]

This will work because any int value other than 0 will return True. Therefore there's an assumption that you aren't using the value 0 for anything meaningful.

2)

Custom id data is removed after bm.free(). I don't know if it can be wiped before.

---

for the sake of completeness

>>> import bmesh
>>> bm = bmesh.new()
>>> obj = bpy.context.active_object
>>> bm.from_mesh(obj.data)
>>> my_id = bm.verts.layers.int.new('id')
>>> bm.verts.ensure_lookup_table()
>>> bm.verts[0][my_id]
0

This shows that even before you assign a specific value to your layer.int for that vertex, it will already have a default 0.