Function resize_guides 

pub fn resize_guides(
    data: &Drawing<'_>,
    id: ShapeId,
    resized: Rect,
) -> Vec<[Pos2; 2]>

Alignment guides for a resize: the shape’s features at its previewed resized rect, matched against every other shape’s resting features. A resize doesn’t translate the shape, so it can’t reuse shape_drag_guides’s offset path.