Development note: Bunyan is in development. This article describes its architectural approach and evaluation considerations.

Bunyan’s development focuses on geometry authoring in the browser. The design uses an Open CASCADE B-Rep kernel compiled to WebAssembly for modelling operations and derives display meshes from the underlying geometry.

Geometry and measurement

A boundary representation describes faces, edges and their geometric relationships. Modelling and measurement can operate on that representation without depending on the resolution of the display mesh. This distinction does not imply unlimited numerical precision: kernel operations use tolerances and remain sensitive to input quality and supported geometry.

Quantities used for contractual purposes need a documented measurement basis, including model completeness, geometric tolerances and applicable measurement rules. A geometric measurement alone does not establish the quantity payable under a contract.

Parametric projects and identity

A project stores objects, their parameters and references. Geometry and views are derived from those definitions. The document model is designed to retain element identity through supported edits and record changes in a revision history.

IFC provides globally unique object identifiers. When an export workflow changes those identifiers, downstream references may need reconciliation. Identity behaviour should be evaluated separately for edits, deletion and recreation, splits, merges and imported revisions.

Evaluation trade-offs

Running a geometry kernel in the browser introduces download, memory and computation costs. Evaluation should measure these costs using representative project geometry and devices. Bunyan’s authoring catalogue and export workflows remain in development; no hosted application is currently available.