Module geometry 

Axis-aligned rectangles — the geometry the layout algebra renders to.

A Rect is the bounding box a crate::LayoutNode subtree is allotted. The unit is the caller’s: tear-core measures in terminal cells (cols × rows), mado scales the same rects to device pixels for the GPU. One crate::LayoutNode::compute_rects algorithm serves both — so a split looks identical whether the daemon is sizing a PTY winsize or mado is drawing pane borders. That single-renderer property is the whole reason this type lives in tear-types and not in either app (the compounding directive’s “solve once” rule).

Cells are u16 — a terminal never exceeds 65535 cols/rows, and the width/height of a child is always ≤ its parent, so no arithmetic here overflows. Division is gap-free and overlap-free by construction: a split hands side a a clamped extent and side b the exact remainder, so a.right() == b.x (or a.bottom() == b.y) always — there is no representable layout with a one-cell seam or a one-cell double-draw.

Structs

Rect

An axis-aligned rectangle in a discrete cell grid. x/y are the top-left origin; w/h are width/height. A zero-area rect is legal (it models a pane squeezed out of a too-small window) but Rect::is_empty flags it so renderers can skip it.