Geometry and nested coordinates

Bounds

interface ArchiBounds {
  x: number | null;
  y: number | null;
  width: number | null;
  height: number | null;
}

Nested coordinates are relative

ArchiBounds.x/.y on a nested diagram object or note are relative to its own parent’s origin, not absolute canvas coordinates — this is how Archi itself stores nested geometry natively.

A diagram object with parentId: 'group-1' and bounds: { x: 10, y: 10, ... } sits 10px right and 10px down from group-1’s own top-left corner, not the view’s.

To get absolute coordinates, sum x/y up the parentId chain to the root. Root-level objects (parentId === null) already have view-relative (i.e. absolute) coordinates:

function absoluteBounds(
  object: ArchiDiagramObject,
  byId: Map<string, ArchiDiagramObject>,
): ArchiBounds | null {
  let current = object;
  let offsetX = 0;
  let offsetY = 0;

  while (current.parentId) {
    const parent = byId.get(current.parentId);
    if (!parent?.bounds?.x || !parent?.bounds?.y) break;
    offsetX += parent.bounds.x;
    offsetY += parent.bounds.y;
    current = parent;
  }

  return object.bounds
    ? {
        x: object.bounds.x !== null ? object.bounds.x + offsetX : null,
        y: object.bounds.y !== null ? object.bounds.y + offsetY : null,
        width: object.bounds.width,
        height: object.bounds.height,
      }
    : null;
}

Nullable fields are meaningful

Any of the four fields can independently be null — the parser never fabricates a 0 for a missing/non-numeric attribute. validateArchiModel does not check bounds completeness; treat a null field as “cannot be positioned”.

Bendpoints

interface ArchiBendpoint {
  startX: number | null;
  startY: number | null;
  endX: number | null;
  endY: number | null;
}

ArchiBendpoint values follow Archi’s own native representation: each bendpoint stores its own start/end pair rather than a single midpoint, which lets a bent connection curve be reconstructed without additional geometry logic.