Importable Data

Data in the file

How the data is handled when imported

LandXML files can contain any number of points (referred to as COGO points in the LandXML format).

When points are imported:

• They become points with associated coordinates and can be edited. These points can be referenced by a surface.
• Their point IDs are based on the "name" field in the file.
• Their feature codes are based on the "desc" field in the file.

ISOLandXML

• Complex feature structures
• Desc attribute (required)
• SurveyOrder support

LandXML-TBC

• FeatureRef for feature linking
• Simple coordinate structure
• Name (required, others optional)

• LandXML-TBC
• Contours
• Contour line data within surfaces
• Elevation-based contour definitions

LandXML files can contain any number of alignments. The required component of an alignment object is a geometric definition of the horizontal alignment.

Required attributes include the name, alignment length, and beginning station value. Optional attributes include station equations, the profile, and cross-section components.

When alignments are imported:

• They are placed on new layers if the "alignment" sections of the file have unique names.
• Their names are based on the "name" field in the file.
• Their geometric definitions are used to create alignments, with the geometry defining the horizontal component of the alignment. Horizontal alignment geometry can consist of lines, arcs, and spirals.
• If the "name" attribute exists in the geometric definition, it is used to name the horizontal alignment.
• The starting station value from the alignment object is used to station the horizontal alignment.
• The alignment may also contain one or more vertical alignments (profiles). If a vertical alignment exists:
  • It is used to create a representation of the vertical alignment in the profile view.
  • The "name" attribute is used to name the vertical alignment.
• If the alignment contains stored cross-sections:
  • The stored cross-sections appear in both the Plan View and the Cross-section View.
  • A surface is automatically created using the cross-section station values, offsets, and elevations upon import. The surface is named using the file name.
• Infrastructure types:
  • SpiralType: clothoid, bloss, cubic, cubicParabola, railroad, sineHalfWave vs clothoid, cubic, biquadratic; LandXML v1.2 does not contain a 'railroad' spiral type, but TBC reads and writes that spiral type.
  • FlowDirection: in, out, vs in, out, both

• Cant (available for import, but not export)
  • Railway/road banking information
  • Superelevation data
  • Missing SpeedStation on import
• Roadways
  • Road-specific feature collections
  • Route-based organization

LandXML files can contain any number of surfaces. A surface can be defined in the file in either (or both) of two ways:

• Source Data - This definition includes the points, point lists, boundaries, breaklines, and contours used to create the surface. This data imports as objects that are separate from the surface, meaning that you can add or remove them from the surface, or edit their properties.
• Definition - This definition includes 3D points and triangles defining the surface. This data imports as an integral part of the surface. This method can support holes and islands in surfaces.
• Breaklines
• DataPoints
• Boundaries (with trimming options)
• No contours (defined in the v1.2 schema)

• Surface and geometry types:
  • SurfaceState: existing, proposed vs stateType: abandoned, destroyed, existing, proposed
  • SurfaceType: TIN, grid vs surfTypeEnum: TIN (fixed value)
  • BreaklineType: standard (fixed) vs standard, wall, proximity, nondestructive

• Utility lines/pipes - If an imported pipe's properties are already defined in the Material and Site Improvement Manager (MSIM), that definition is used; it is not overwritten. If the imported pipe's name is the same, but dimensions are different, a new MSIM object is created; the name is appended with the new dimension. Imported user-defined shapes come in as rectangular pipe shapes defined by the cross-sectional bounding box.
• date
• time
• version (set to v1.2)
• xs:anyAttribute (allows extensions)
• xmlns (required)
• readOnly (required)
• language (required)
• FeatureDictionary
  • ISO15143-4 feature extension definitions
  • Version control for taxonomies

ISOLandXML - Certain International System of Units (SI), aka metric

• Fixed values: meter, squareMeter, cubicMeter, celsius, milliBars, radians
• No unit flexibility
• Although the ISO standard has milliBars listed as the unit of pressure, the correct SI pressure unit is HPA (hectopascal (1 hPa = 100 Pa), equal to one millibar).

LandXML-TBC - Dual System

• Imperial: foot, USSurveyFoot, inch, mile, squareFoot, cubicFeet, fahrenheit, inHG
• Metric: millimeter, centimeter, meter, kilometer, squareMeter, cubicMeter, celsius, HPA
• Angular: radians, grads, decimal degrees, decimal dd.mm.ss

Coordinate system
(Missing from the ISOLandXML, but present in the v1.2 schema)

• EPSG code support
• OGC WKT code support
• Coordinate system definitions

ISOLandXML - Complex Taxonomy

• ISO15143-4 feature codes
• Union types for property labels
• Hierarchical feature classification

LandXML-TBC - Simple Structure

• Basic label/value property pairs
• Optional feature codes
• Minimal validation

ISOLandXML

• No material attributes in Pipe or Struct types (desc instead)

LandXML-TBC

• Material attributes in Pipe and Struct types