This is a United States Geological Survey (USGS) format. SDTS has a raster and a vector format. The raster format is not supported in MapServer. Only the vector formats are supported, including VTP and DLG files.
This example uses transportation data, which consists of 35 separate files, each with the suffix DDF:
MDTRAHDR.DDF MDTRARRF.DDF MDTRCATS.DDF
MDTRDQCG.DDF MDTRFF01.DDF MDTRLE02.DDF
MDTRNA03.DDF MDTRNO03.DDF MDTRSPDM.DDF
MDTRAMTF.DDF MDTRBFPS.DDF MDTRCATX.DDF
MDTRDQHL.DDF MDTRIDEN.DDF MDTRLE03.DDF
MDTRNE03.DDF MDTRPC01.DDF MDTRSTAT.DDF
MDTRARDF.DDF MDTRBMTA.DDF MDTRDDSH.DDF
MDTRDQLC.DDF MDTRIREF.DDF MDTRNA01.DDF
MDTRNO01.DDF MDTRPC02.DDF MDTRXREF.DDF
MDTRARDM.DDF MDTRCATD.DDF MDTRDQAA.DDF
MDTRDQPA.DDF MDTRLE01.DDF MDTRNA02.DDF
MDTRNO02.DDF MDTRPC03.DDF
Using ogrinfo on a catalog file (note that the first 7 layers do not have geometries):
> ogrinfo /data/sdts/MD/MDTRCATD.DDF
Had to open data source read-only.
INFO: Open of `MDTRCATD.DDF'
using driver `SDTS' successful.
1: ARDF (None)
2: ARRF (None)
3: AMTF (None)
4: ARDM (None)
5: BFPS (None)
6: BMTA (None)
7: AHDR (None)
8: NE03 (Point)
9: NA01 (Point)
10: NA02 (Point)
11: NA03 (Point)
12: NO01 (Point)
13: NO02 (Point)
14: NO03 (Point)
15: LE01 (Line String)
16: LE02 (Line String)
17: LE03 (Line String)
18: PC01 (Polygon)
19: PC02 (Polygon)
20: PC03 (Polygon)
Using ogrinfo to examine the structure of the file/layer:
> ogrinfo /data/sdts/MD/MDTRCATD.DDF LE01 -summary
Had to open data source read-only.
INFO: Open of `MDTRCATD.DDF'
using driver `SDTS' successful.
Layer name: LE01
Geometry: Line String
Feature Count: 780
Extent: (-80.000289, 36.999774) - (-74.999711, 40.000225)
Layer SRS WKT:
GEOGCS["NAD27",
DATUM["North_American_Datum_1927",
SPHEROID["Clarke 1866",6378206.4,294.978698213901]],
PRIMEM["Greenwich",0],
UNIT["degree",0.0174532925199433]]
RCID: Integer (0.0)
SNID: Integer (0.0)
ENID: Integer (0.0)
ENTITY_LABEL: String (7.0)
ARBITRARY_EXT: String (1.0)
RELATION_TO_GROUND: String (1.0)
VERTICAL_RELATION: String (1.0)
OPERATIONAL_STATUS: String (1.0)
ACCESS_RESTRICTION: String (1.0)
OLD_RAILROAD_GRADE: String (1.0)
WITH_RAILROAD: String (1.0)
COVERED: String (1.0)
HISTORICAL: String (1.0)
LIMITED_ACCESS: String (1.0)
PHOTOREVISED: String (1.0)
LANES: Integer (2.0)
ROAD_WIDTH: Integer (3.0)
BEST_ESTIMATE: String (1.0)
ROUTE_NUMBER: String (7.0)
ROUTE_TYPE: String (9.0)
Map File Example:
LAYER
NAME sdts_maryland
TYPE LINE
CONNECTIONTYPE OGR
CONNECTION "data/sdts/MD/MDTRCATD.DDF"
DATA "LE01"
STATUS DEFAULT
CLASS
STYLE
COLOR 0 0 0
END
END
END