The Bounding-Box Model

Bounding boxes are the common currency of layout: nearly every pass produces, consumes, or unions them. This essay will document the BoundingBox type and its operations.

Planned contents

• The BoundingBox representation and its invariants (minX <= maxX, etc.).
• Construction and validation helpers (bbox, empty).
• Geometric operations — union, intersection, transformation.
• How bounding boxes flow through domain inference, layout, and placement.
• The relationship between intrinsic dims, transforms, and final boxes.
• Baseline. A node's bbox carries more than just min/max along each axis; it also carries a baseline — a per-axis reference offset that lets a parent align children by something other than their geometric center or edge (e.g. typographic baseline for text, the wide point of an arrow head, the center-of-mass of an irregular shape). Cover where the baseline is consumed (alignment in stackX/stackY, position, label placement) and how a shape declares its own baseline rather than letting the default geometric one stand.

Source

Likely covers:: packages/gofish-graphics/src/util/bbox.ts. Add the covers: frontmatter when writing this up, then run pnpm --filter docs sync-backlinks.