trying to box select vertices doesn't select all vertices

Question

I'm trying to Box Select some vertices but for some reason it has problems selecting overlapping vertices.

Here's a video that demonstrates this behaviour: https://streamable.com/hvj34

What am I doing wrong here?

Thanks

Answer 1

The selection tools by default only select vertices not hidden by other faces. In your case, the vertices very close to each other (on on the same point) are preventing one or other of each pair from being selected.

To avoid this ‘masking’ you can swap to wireframe mode (Z) before making the selection. This will allow you to select all vertices within the box region.