| Data Content - GDF | |
01
Each volume starts with a Volume Header. This header specifies the Album to which the Volume belongs and it specifies the links to the datasets to which it belongs or that it contains. In MultiNet® GDF-AS, the Volumes are considered independent of each other and therefore always carry an identification of "1."
0201
This record marks the beginning of a new Dataset and the end of the previous one. This record contains the supplier dataset ID and also identifies the languages used in the dataset.
0202
This record names the dataset.
0206
These records list the Feature themes that may be contained in the dataset.
03
These records identify and define all the record fields that may be contained in the dataset.
04
These records identify all the record types that may be contained in the dataset.
05
These records identify all the Attributes that may be contained in the dataset.
07
These records identify the Feature Types that may be contained in the dataset.
09
These records define Relationships that may be contained in the dataset.
10
These records name and define the Administrative Type Structures that may be contained in the dataset.
15
These records identify the default Attribute values for each Attribute type that may be contained in the dataset.
18
These records define all Attribute values that may be contained in the dataset.
61
This record does not contain any datum or ellipsoid information at this time.
66
Constructions that may influence the earth's magnetic field include: bridges, tunnels, power lines, electric railways and tramways. These records identify latitude and longitude coordinates where variations between magnetic north and geographic north have been measured.
1601
This record contains the Section ID and the geographic region that the following records apply to. In TomTom® MultiNet® GDF products, Sections are defined based on Administrative Areas. Usually Sections are defined based on Municipality Borders. By default one section contains one municipality. The "GEO_AREA" field contains the Municipality Name. Exceptions exist where one section contains multiple municipalities. In that case the "GEO_AREA" field contains the name of one of the contained Municipalities. For all other contained Municipalities the Section Identification Subrecord is repeated for each municipality but stored as a "Comment Record" (90) having the same structure as the Section Identification Record.
1607
This record contains the bounding coordinates of the section.
17
The layer header record contains the layer ID within the section and a coded list of features represented in the layer. There are a number of unused fields in this record (always blank).
Example: Layer Header Record
17 1 111131414243717590929397
| GDF THEME CODE | DESCRIPTION |
|---|---|
| 11 | Administrative Areas |
| 31 | Settlements and Named Areas |
| 41 | Roads and Ferries |
| 42 | Railways |
| 43 | Waterways |
| 50 | Public Transport |
| 71 | Land Cover and Use |
| 72 | Road Furniture |
| 73 | Services |
| 75 | Brunnels |
| 80 | General Purpose Features |
| 90-99 | User-Defined Features |
23
The coordinates record is the root geographic location record that is referenced in the New Node record (25) and Edge Record (24) via the XYZ_ID.
25
Nodes are a Level 0 feature. As such, they are one of the three geometric primitives that lay the foundation for building more complex features.
See Feature Representation - Level 0 earlier in this user guide.
24
Edges are a Level 0 feature. As such, they are one of the three geometric primitives that lay the foundation for building more complex features.
See Feature Representation - Level 0 earlier in this user guide.
Edge records contain all necessary IDs and information to represent an edge and to connect to any feature that is built from an edge or contains an edge.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
29
Faces are a Level 0 feature. As such, they are one of the three geometric primitives that lay the foundation for building more complex features.
See Feature Representation - Level 0 earlier in this user guide.
Face records contain all edge records comprising each face. Each edge record identified also contains its digitized orientation in relation to the face. Edges describing the boundary of a face are consecutively ordered in a clockwise orientation for the main polygon of the face. If an edge is digitized in a counterclockwise direction, it is assigned a value of "1" in the Orient field of this record.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
51
Points are a Level 1 feature.
See Feature Representation - Level 1 earlier in this user guide.
Point records contain the Point ID, the feature code associated with the point, the associated node or knot primitive and reference to segmented attribute IDs, if applicable.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
52
Lines are a Level 1 feature.
See Feature Representation - Level 1 earlier in this user guide.
Line records contain the Line ID, the feature code associated with the line, the associated edge primitive(s) and relation to their direction and reference to segmented attribute IDs. The bounding points of the line also are identified.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
53
Areas are a Level 1 feature.
See Feature Representation - Level 1 earlier in this user guide.
Area records contain the Area ID, the feature code associated with the area, the associated face primitive(s) and reference to segmented attribute IDs.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
54
Complex features are Level 2 features.
See Feature Representation - Level 2 earlier in this user guide.
Complex feature records contain the Complex Feature ID, the feature code associated with the complex feature, the associated lower level features or other complex features and reference to segmented attribute IDs.
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
41
Name records contain names associated with a feature and a reference to the feature's Segmented Attribute Record(s).
See also Data Record Relations earlier in this section.
44
See also Data Record Relations and Data Record Field Pointers - GDF-AS earlier in this section.
46
Conversion Records are used as a link between features that lie on a section border or between the parts of a feature that lie in different sections (features that are "split"). A full discussion of Conversion Records and Split Indicators, their representation and use in MultiNet® data, is found in the Dataset and Section Crossing portion of this user guide.
See also Conversion Records later in this user guide for a general overview.
50
Relationship records show full feature reference (GDF Datasets, GDF Section ID, and GDF Feature ID. For a list of relationship codes, refer to the allcodes database included in your data delivery.
See Relationships earlier in this user guide for a general overview.
45
See Time Domains earlier in this user guide for a general overview. See also the Appendix section of the MultiNet® Data Specification on this documentation DVD for a description of GDF Time Domains.
83
The Object Reference Record is used to link add-on objects directly to the core map. This record is not used for the standalone map.
90
The Volume Termination Record concludes all the records contained in the volume that began with the Volume Header record.