debugPreview property
The cached preview's five lines in world, as paintRubberBand draws them; empty when none is shown.
Implementation
@visibleForTesting
List<(Vector2, Vector2)> get debugPreview => [
if (_hasPreview)
for (var i = 0; i < 20; i += 4)
(
Vector2(_preview[i], _preview[i + 1]),
Vector2(_preview[i + 2], _preview[i + 3]),
),
];