Abstract
Layered export of building-model drawings requires each layer to be drawn in a separate pass, which defeats hidden-line removal between layers: the order in which passes are written decides what covers what. This disclosure describes two methods, used in Motion-Site's CAD (DXF) Layer Exporter and PDF Layer Exporter for Autodesk Revit, that export views and sheets to layered DXF and PDF while preserving the visual stacking of the original drawing. A depth-band engine projects every element into the view, gives each element a coarse depth buffer, decides each overlapping pair once, orders layers with a dominance graph, splits layers into passes only where crossings require it, and releases only the weakest relation of each occlusion cycle. A second engine, EXACT STACK, computes no depth from geometry: it rewrites Revit's own element-tagged PDF print into optional-content layers, including elements of linked models, reads occlusion from per-layer prints, orders elements by approximating a minimum feedback arc set, and restores hidden ink as underlays shown only where every covering layer is switched off. Layer definition by rule sets and parameter values, linked-model elements, multi-view sheets and variations of each mechanism are also described.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Recommended Citation
Pushchinskyi, Andrii, "Exporting Revit Views and Sheets to Layered DXF and PDF While Preserving Draw Order", Technical Disclosure Commons, ()
https://www.tdcommons.org/dpubs_series/12470