|
|
Home | Products | Issue Tracker | FAQ | Download |
|
|
Table of Contents
Keyhole Markup Language (KML) is an XML-based language for managing the display of 3D geospatial data. KML is a standard maintained by the Open Geospatial Consoritum (OGC).
KML access in MapServer is available through OGR. See the OGR driver page for specific driver information. Read support was initially added to GDAL/OGR version 1.5.0. A more complete KML reader was added to GDAL/OGR in version 1.8.0, through the libKML driver (including the ability to read multigeometry, and KMZ files).
The CONNECTION parameter must include the kml or kmz extension, and the DATA parameter should be the name of the layer.
CONNECTIONTYPE OGR
CONNECTION "filename.kml"
DATA "layername"
First you should make sure that your GDAL/OGR build contains the “KML” driver, by using the ‘–formats’ command:
>ogrinfo --formats
Loaded OGR Format Drivers:
...
-> "GML" (read/write)
-> "GPX" (read/write)
-> "KML" (read/write)
...
If you don’t have the driver, you might want to try the FWTools or MS4W packages, which include the driver.
Once you have the KML driver you are ready to try an ogrinfo command on your file to get a list of available layers:
>ogrinfo myplaces.kml
INFO: Open of `myplaces.kml'
using driver `KML' successful.
1: Layer #0 (Point)
Now use ogrinfo to get information on the structure of the layer:
>ogrinfo fountains-hotel.kml "Layer #0" -summary
Had to open data source read-only.
INFO: Open of `fountains-hotel.kml'
using driver `KML' successful.
Layer name: Layer #0
Geometry: Point
Feature Count: 1
Extent: (18.424930, -33.919627) - (18.424930, -33.919627)
Layer SRS WKT:
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.01745329251994328,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]]
Name: String (0.0)
Description: String (0.0)
LAYER
NAME "kml_example"
TYPE POINT
STATUS DEFAULT
CONNECTIONTYPE OGR
CONNECTION "kml/fountains-hotel.kml"
DATA "Layer #0"
LABELITEM "NAME"
CLASS
NAME "My Places"
STYLE
COLOR 250 0 0
OUTLINECOLOR 255 255 255
SYMBOL 'circle'
SIZE 6
END
LABEL
SIZE TINY
COLOR 0 0 0
OUTLINECOLOR 255 255 255
POSITION AUTO
END
END
END
First you should make sure that your GDAL/OGR build contains the “LIBKML” driver, by using the ‘–formats’ command:
>ogrinfo --formats
Loaded OGR Format Drivers:
...
-> "GML" (read/write)
-> "GPX" (read/write)
-> "LIBKML" (read/write)
-> "KML" (read/write)
...
If you don’t have the driver, you might want to try the FWTools or MS4W packages, which include the driver. Or you can follow the compiling notes for libKML and GDAL/OGR.
Once you have the LIBKML driver you are ready to try an ogrinfo command on your file to get a list of available layers:
>ogrinfo Lunenburg_Municipality.kmz
INFO: Open of `Lunenburg_Municipality.kmz'
using driver `LIBKML' successful.
1: Lunenburg_Municipality
Now use ogrinfo to get information on the structure of the layer:
>ogrinfo Lunenburg_Municipality.kmz Lunenburg_Municipality -summary
INFO: Open of `Lunenburg_Municipality.kmz'
using driver `LIBKML' successful.
Layer name: Lunenburg_Municipality
Geometry: Unknown (any)
Feature Count: 1
Extent: (-64.946433, 44.133207) - (-64.230281, 44.735125)
Layer SRS WKT:
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
TOWGS84[0,0,0,0,0,0,0],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9108"]],
AUTHORITY["EPSG","4326"]]
Name: String (0.0)
description: String (0.0)
timestamp: DateTime (0.0)
begin: DateTime (0.0)
end: DateTime (0.0)
altitudeMode: String (0.0)
tessellate: Integer (0.0)
extrude: Integer (0.0)
visibility: Integer (0.0)
LAYER
NAME "lunenburg"
TYPE POLYGON
STATUS DEFAULT
CONNECTIONTYPE OGR
CONNECTION "Lunenburg_Municipality.kmz"
DATA "Lunenburg_Municipality"
CLASS
NAME "Lunenburg"
STYLE
COLOR 244 244 16
OUTLINECOLOR 199 199 199
END
END
END # layer