single default selection
zones: 1 / topology: single / positions: [primary]
candidate_when: unit_count = 1
horizontal-2 default selection
zones: 2 / topology: rows / positions: [top, bottom]
candidate_when: unit_count = 2 / orientation = horizontal
vertical-2 alternative
zones: 2 / topology: cols / positions: [left, right]
candidate_when: unit_count = 2 / orientation = vertical
top-1-bottom-2 default selection
zones: 3 / topology: T / positions: [top, bottom-left, bottom-right]
top
bottom-left
bottom-right
candidate_when: unit_count = 3 / layout = T
top-2-bottom-1 alternative
zones: 3 / topology: inverted-T / positions: [top-left, top-right, bottom]
top-left
top-right
bottom
candidate_when: unit_count = 3 / layout = inverted-T
left-1-right-2 alternative
zones: 3 / topology: side-T-left / positions: [left, right-top, right-bottom]
left
right-top
right-bottom
candidate_when: unit_count = 3 / layout = side-T-left
left-2-right-1 alternative
zones: 3 / topology: side-T-right / positions: [left-top, right, left-bottom]
left-top
right
left-bottom
candidate_when: unit_count = 3 / layout = side-T-right
grid-2x2 default selection
zones: 4 / topology: 2x2 / positions: [top-left, top-right, bottom-left, bottom-right]
top-left
top-right
bottom-left
bottom-right
candidate_when: unit_count = 4