LandXML — Surveying & Civil Engineering Data Exchange
Open BetaLandXML is an open XML vocabulary from the Autodesk, Bentley, and Trimble consortium (1999) for exchanging civil engineering and surveying data between AutoCAD Civil 3D, Bentley OpenRoads, Trimble Business Center, and Russian CREDO, IndorCAD, Topomatic. Our exporter produces a valid LandXML 1.2 document: buildings become Parcel elements with CoordGeom geometry, roads become PlanFeature from Line segments, and point objects become CgPoint. Honest about limits: coordinates are emitted in WGS84 (lat/lon), not a projection, so before designing in Civil 3D they must be re-registered to a local metric system (UTM, national grid). We write straight segments with no transition clothoids — OSM stores no curve parameters — so this is an OSM context basemap, not a geodetically verified survey.
Tính năng chính
Giới thiệu về định dạng LandXML
LandXML is an open XML vocabulary for exchanging survey and civil engineering data: parcels, alignments, surfaces, survey points. It is supported by AutoCAD Civil 3D, Bentley OpenRoads and Trimble Business Center, and among Russian packages by CREDO, IndorCAD and Topomatic, which keeps the format a neutral bridge between different schools of software.
OpenStreetMap maps are exported to LandXML for the sake of context in a project: the streets and blocks next to the site, showing the surroundings of a future road or platform. It is a base plan for the concept stage, not a replacement for a survey.
In a LandXML 1.2 document buildings become Parcel objects (green zones are marked as Open Space, other polygons as Lot), roads become PlanFeature elements made of straight segments, and point features become CgPoint. Names are taken from the name, addr:street and ref tags, so streets and addresses read right in the object list. The limit is 50,000 objects per file.
Two honest limitations. Coordinates are written out in WGS84, that is in degrees of latitude and longitude, whereas LandXML is meant for flat metric coordinates — before working, the data has to be reprojected into a local system (UTM, MSK, State Plane). And curves: OSM stores roads as polylines, so there are no radii and no transition spirals in the file, and the horizontal alignment geometry has to be built anew.
Chương trình nào mở được tệp LandXML
Các chương trình và ứng dụng sau có thể mở, chỉnh sửa và làm việc với tệp LandXML — Surveying & Civil Engineering Data Exchange (.xml) được xuất từ OSM2CDR:
Format specifications
- Open standard
- 2D only
- Lossless (no quality loss)
- Stores feature attributes
- Output: 1 file
- A valid LandXML 1.2: buildings -> Parcel, roads -> PlanFeature of straight Line segments, points -> CgPoint; coordinates in WGS84 (not projected), no transition clothoids.
Ai sử dụng bản đồ LandXML
Cách xuất LandXML
Cách mở tệp sau khi xuất
- AutoCAD Civil 3D — Import LandXML; first assign a local coordinate system to the drawing, otherwise objects in degrees will collapse into a point at the origin.
- Reprojecting beforehand — ogr2ogr or QGIS will convert the data into UTM or MSK, if it is more convenient to get metric coordinates before importing.
- Bentley OpenRoads Designer and Trimble Business Center — a standard LandXML import, with the same order of operations for the coordinate system.
- CREDO, IndorCAD, Topomatic — LandXML import exists in these product lines; after loading, check that the units were read as meters.
- Viewing without CAD — the file is text: xmllint --format will show the structure with the Units, CoordinateSystem, Parcels, PlanFeatures and CgPoints blocks.
Bản đồ phổ biến ở định dạng LandXML
Nhận bản đồ xuất ở định dạng LandXML — Surveying & Civil Engineering Data Exchange
Tải bản đồ LandXML chuyên nghiệp từ OpenStreetMap. Tạo tức thì, bất kỳ khu vực nào.