CreateDataSourceOverlay Method

Description

Inserts a dataset into the current SIS Workspace Definition (SWD), which will fetch data from non-file data source.

See OGC WMS for a full description.

Syntax

Public Function CreateDataSourceOverlay( _
   ByVal pos As Integer, _
   ByVal clsDataSource As String, _
   ByVal parameters As String _
) As Integer

Parameters

pos

The position in the overlays list at which to insert the overlay. If this argument specifies a position in the existing overlays, the new overlay will not replace the existing overlay at the given position, but will shuffle any other overlays down the list.

 

clsDataSource

The classname of the data source to use.

 

parameters

Comma-separated optional parameters to configure the data source.

Remarks

Notes:

Mandatory parameters will be coloured RED.

Examples using params = {} are based on Python.

Oracle Spatial

clsDataSource = "AOracleSpatialCursorDts"

Example

In VB:

Dim params As String

Params = "user=MYLOGIN,password=MYPWD,service=MYDBSVR,table=MYTABLE,cache=true"

GisCreateDataSourceOverlay (1,"AOracleSpatialCursorDts ",params)

PostGIS

clsDataSource = "APostGisCursorDts"

PostGIS Raster

clsDataSource = "PostGISRasterDataset"

Parameter	Type	Comments
host	String
port	String
database	String
user	String
password	String
schema	String	Typically "public"
rastertable	String	Equivalent to "table" in PostGIS
rastercolumn	String	Equivalent to "geometrycolumn" in PostGIS
Plaintext	Boolean	Set to "True" if passing a non-encrypted password when the server is expecting encryption. An encrypted password is assumed by default, in this case do not specify the Plaintext parameter.
connectiontype	String	"dynamic" "import" "local"
showerrors	Boolean

Tile Map Service

clsDataSource = "TileMapServiceDataset"

params = {}
params['url'] = 'http://server:port/osgeoservice/tms/1.0.0/image-format/projection/name_of_layer_being_served.xml'

sis.CreateDataSourceOverlay(0, 'TileMapServiceDataset', json.dumps(params))

Open Street Map

clsDataSource = "OpenStreetMapDatasetEx"

Parameter	Type	Comments
Nodes	Boolean
Relations	Boolean
Ways	Boolean
SkipTags	Boolean

Note: It is not mandatory to include all of the above parameters, but at least one must be used

If adding parameters in old style parameter string, also use:

Parameter	Type	Comments
bbox	String	"minx,miny,maxx,maxy"

If adding parameters in (recommended) JSON string style, also use:

Parameter	Type	Comments
Left	Double	Equivalent minx
Bottom	Double	Equivalent miny
Right	Double	Equivalent maxx
Top	Double	Equivalent maxy

Example

String format:

sis.CreateDataSourceOverlay(0, "OpenStreetMapDatasetEx", "bbox=\" 11.54,48.14,11.543,48.145 \",Nodes=True")

JSON format:

p = { "Left":11.54,"Bottom":48.14,"Right":11.543,"Top":48.145,"Nodes": True, "Ways" :True, "Relations": True }

sis.CreateDataSourceOverlay(0, "OpenStreetMapDatasetEx", json.dumps(p))

Open Street Map Tile

clsDataSource = "OpenStreetMapTileDataset"

Parameter	Type	Comments
URL	String	URL to the Tile Server
MaxLevel	Integer	Max. zoom level

Example

params = {}

params["URL"] = "http://tile.openstreetmap.org/<z>/<x>/<revy>.png"

params["MaxLevel"] = 17

sis.CreateDataSourceOverlay(0,"OpenStreetMapTileDataset",  json.dumps(params))

Ordnance Survey DNF MasterMap

clsDataSource = "AOsDnfCursorDts"

Parameter	Type	Comments
Connection	String	Connection needs to be prefixed with ODB or MDB depending on source. See example below.
Table	String	Table is always "MASTERMAP"
points	String	"true" includes point geometry types. "false" doesn't include point geometry types.
lines	String	"true" includes linestrings geometry types. "false" doesn't include linestrings geometry types.
areas	String	"true" includes polygon geometry types. "false" doesn't include polygon geometry types.

Example

Sis.CreateDataSourceOverlay(0,"AOsDnfCursorDts", "Connection=""ODB:c:\\Brighton.odb"", Table=""MASTERMAP"", points=""true"", lines=""true"", areas=""true""")

Notes: In VB.net use double dashes in path names and double quotes for embedded parameter string values.

ESRI File Geodatabase

clsDataSource = "FileGeoDatabaseDataset"

Parameter	Type	Comments
folder	String	Path to GeoDatabase File
table	String	Optional choice of table

GeoJSON

clsDataSource = "GeoJSONFeaturesDatasetEx"

params = {}
params["cache"] = True
params["url"] = "https://url_to_some/geojson_data/geo_data_file.geojson"
sis.CreateDataSourceOverlay(0, "GeoJSONFeaturesDatasetEx", json.dumps(params))

GeoRSS

clsDataSource = "GeoRSSDataset"

TopoJSON

clsDataSource = "TopoJSONFeaturesDatasetEx"

params = {}
params["cache"] = True
params["url"] = "https://url_to_some/topo_json_data/topo_data_file.json"
sis.CreateDataSourceOverlay(0, "TopoJSONFeaturesDatasetEx", json.dumps(params))

ECW

clsDataSource = "ECWDataSource"

Parameter	Type	Comments
url	String	the ECWP URL

ArcIMS

clsDataSource = "ArcIMSDataSource"

Parameter	Type	Comments
url	String	the ArcIMS URL
service	String	the ArcIMS service

EXIF

clsDataSource = "EXIFDataset"

Parameter	Type	Comments
folder	String	path to folder
recurse	String	"true" "false"

GDAL DataSource

clsDataSource = "GDALDataSource"
clsDataSource = "*_GDALDataset"

Parameter	Type	Comments
filename	String	path to file
model	String	Colour Model of raster: "monochrome" "grayscale" "palette" "rgb" "hls" "cmy" "cmyk" "grid" "rgba"
stretch	String	Enable stretch: "true" "false"
method	String	Stretch method: "linear" "squareroot" "logarithmic" "exponential" "equalization" "negative"
trim	Integer	Stretch Tail Trim (%): Number in the range 1 to 5, inclusive
band1	Integer	Number where n can range from 0 to the number of bands -1, inclusive
band2	Integer
band3	Integer
band4	Integer
		Notes on band selection: Band selection always starts with `band1`, which then may be followed by `band2`, which in turn may be followed by `band3`, which in turn may be followed by `band4`. There must be no 'gaps' in the band parameters. For example, the following are valid band selection parameters: band1= band1=,band2= band1=,band2=,band3= band1=,band2=,band3=,band4= Whereas, the following are invalid sequences: band2= band2=,band1= band3=,band2= band1=,band3=,band2= The band indices are not relevant in the above examples and have therefore not been shown.
colour	String	red:green:blue e.g. 255:0:0 for red
algorithm	String	Set the resampling method: "none" "nearestneighbour" "bilinear" "cubic" "cubicspline" "lanczos"

GeoDatabase

clsDataSource = "GeoDatabaseDataset"
tables

GML

clsDataSource = "AGMLImporterEx"

Parameter	Type	Comments
url	String	path to GML file
DefaultItemStatus	Integer	0 invisible 1 visible 2 hittable
Validate	Boolean
PreloadSchema	Integer	Where n is the schema reference: 20102 is GML 2.1.2 30101 is GML 3.1.1 30201 is GML 3.2.1 -1 is Custom Schema (see below parameter)
SwapAxes	Boolean	By default, coordinates are expressed using the axis order defined in the CRS True = force to always swap axes False = force to never swap axes
CustomSchema	String	The path to the XML grammar file to be used. Note: PreloadSchema parameter must be -1

Examples

For C#, either of the two forms:

sis.CreateDataSourceOverlay(0, "AGMLImporterEx", "url=\"file://localhost/D:\\\\data\\\\test.gml\",DefaultItemstatus=2,validate=true,PreloadSchema=30101");

sis.CreateDataSourceOverlay(0, "AGMLImporterEx", @"url=""file://localhost/D:\\data\\test.gml"",DefaultItemstatus=2,validate=true,PreloadSchema=30101");

For VB:

sis.CreateDataSourceOverlay(0, "AGMLImporterEx","url=""file://localhost/D:\\data\\test.gml"",DefaultItemstatus=2,validate=true,PreloadSchema=30101")

For Python, either of the two forms:

sis.CreateDataSourceOverlay(0, "AGMLImporterEx","url=\"file://localhost/D:\\\\data\\\\test.gml\",DefaultItemstatus=2,validate=true,PreloadSchema=30101")

sis.CreateDataSourceOverlay(0, "AGMLImporterEx","url=\"file://localhost/D:/data/test.gml\",DefaultItemstatus=2,validate=true,PreloadSchema=30101")

or serialising parameters from dictionary object to JSON string, then no extra escaping of backslashes \\\\ or double quotes \" is required:

params = {
"DefaultItemstatus":2,
"validate":1
"PreloadSchema":30101,
"url":"file://localhost/D:\\data\\test.gml"
}
sis.CreateDataSourceOverlay(0, "AGMLImporterEx", json.dumps(params)) 

Note: For API methods that take a list of string as a single parameter, Cadcorp recommend passing the list as a JSON string.

NGA Digital Nautical Chart

clsDataSource = "DNCDataSource"
clsDataSource = "DNCDataSourceEx"

Parameter	Type	Comments
directory	String	Path to folder containing NGA Digital Nautical Chart LHT file.
coverage	String	Name of coverage to add (as defined in the folder name)
lon	Integer	Centre longitude (degrees)
lat	Integer	Centre latitude (degrees)
width	Integer	Extents (degrees), Width (E/W)
height	Integer	Extents (degrees), Height (N/S)

The clsDataSource, "DNCDataSource", allows you to add an individual coverage. To load multiple coverages at once, use clsDataSource = "DNCDataSourceEx". It requires the same parameters as above as well as:

The clsDataSource, "ADcwDts", uses slightly different parameter names, as follows:

Oracle Geo Raster

clsDataSource = "OracleGeoRasterDataset"

Example:

VB.net:

Dim connection As String
connection = "OCI:User=qa;Password=spatial;Service=\""//10.0.0.22:1521/orcl.cadcorp.net\"""

Dim params As String
params = "{"
params += """connection"":""" + connection + """"
params += ","
params += """connectiontype"":""import"""
params += ","
params += """georastertable"":""SIS_GEORASTER_EXPORT"""
params += ","
params += """georastercolumn"":""GEORASTER"""
params += ","
params += """showerrors"":true"
params += ","
params += """rdttable"":""SIS_RDT"""
params += ","
params += """rasterid"":""12"""
params += ","
params += """owner"":""qa"""
params += "}"

sis.CreateDataSourceOverlay(0, "OracleGeoRasterDataset", params)

Oracle Network

clsDataSource = "OracleNetworkDataSource"

Parameter	Type	Comments
service	String
user	String
password	String
Plaintext	Boolean	Set to "True" if passing a non-encrypted password when the server is expecting encryption. An encrypted password is assumed by default, in this case do not specify the Plaintext parameter.
showerrors	Boolean
network	String

Example:

Sis.CreateDataSourceOverlay(0, "OracleNetworkDataSource", "connection=""OCI:service=orac10g2;user=spatial;password=spatial"",showerrors=true,network=TEST11"

Ordnance Survey Address

clsDataSource = "OsDnfAddressDataset"
clsDataSource = "OsDnfITNDataset"

Parameter	Type	Comments
folder	String	Path to folder containing the dataset
recurse	String	"true" "false"

Ordnance Survey Imagery

clsDataSource = "OsDnfImageryDataset"
clsDataSource = "OsDnfIndexDataset"

Parameter	Type	Comments
folder	String	Path to folder containing the dataset
recurse	String	"true" "false"
label	String	"true" "false"
gatewaylimit	Integer

OS (GB) Meridian 2

clsDataSource = "OSMeridian2Dataset"

Parameter	Type	Comments
folder	String	Path to folder containing the dataset

OGC CityGML Document

clsDataSource = "ACityGMLImporterEx"

OGC OWS Context Document

clsDataSource = "AOgcOwsContextDatasetEx"

Parameter	Type	Comments
url	String
showerrors	Boolean
cascadetowmc	Boolean	Controls whether to check WMSContext instead of an OWSContext document

OGC WMS Context Document

clsDataSource = "AOgcWmsContextDatasetEx"

Parameter	Type	Comments
url	String
showerrors	Boolean

OGC KML

clsDataSource = "KMLDatasetEx"

Parameter	Type	Comments
url	String	URL to KML data

Raster Index Dataset

clsDataSource = "RasterIndexDataset"

Parameter	Type	Comments
directory	String	path to folder containing rasters
scale	Integer
gatewaylimit	Integer
recurse	Boolean

SDE

clsDataSource = "SDEDataSource"

Parameter	Type	Comments
connection	String	"username/password@service"
extents	String	"lox, loy, hix, hiy"
layerid
dynamic	String	"true" "false"

SQL Server

The parameter string for a SQL Server connection must be a valid JSON string which contains following parameter:

connection: A connection string which contains the provider (SQLOLEDB.1), data source (server), catalog, password, and user id.

The following “connection” string is valid for a Microsoft SQL Server Connection which is represented in the Add Database Overlay dialog.

"connection":
"Provider=SQLOLEDB.1;
Password=spatial;
Persist Security Info=True;
User ID=username;
Initial Catalog=spatial;
Data Source=servername;"

datasource: The Table/Datasource (_dataSource$).

geometrycolumn: The geometry field from the SQL Server table (_geometryColumn$).

wkt: A well known text which describes the CRS coordinate reference system of the new data source overlay.

The following “wkt” string is valid for a new data source overlay which uses the British National Grid (OGC.OSGB_1936) as CRS. Other CRS WKT need to be built as JSON from the OGC Well-known Text in the Cadcorp SIS Named Object Library.

"wkt":
"PROJCS[\"OSGB 1936.British National Grid\",
GEOGCS[\"Latitude/Longitude.OGC.OSGB_1936\",
DATUM[\"OSGB_1936\",
SPHEROID[\"Airy 1830\",6377563.396,299.32496460007]],
PRIMEM[\"Greenwich\",0],
UNIT[\"degrees\",0.0174532925199433]],
PROJECTION[\"Transverse_Mercator\"],
PARAMETER[\"Central_Meridian\",-2],
PARAMETER[\"False_Easting\",400000],
PARAMETER[\"False_Northing\",-100000],
PARAMETER[\"Latitude_of_Origin\",49],
PARAMETER[\"Scale_Factor\",0.9996012717],
UNIT[\"m\",1]]"

cache: boolean

readonly: boolean

Below is a complete example of a JSON parameter string for a SQL Server (ASQLServerCursorDts) datasource connection:

{
"connection":
"Provider=SQLOLEDB.1;
Password=spatial;
Persist Security Info=True;
User ID=username;
Initial Catalog=initialcat;
Data Source=datasource;",
"datasource": "LOCKTABLE1",
"geometrycolumn": "GEOMETRY",
"wkt":
"PROJCS[\"OSGB 1936.British National Grid\",
GEOGCS[\"Latitude/Longitude.OGC.OSGB_1936\",
DATUM[\"OSGB_1936\",
SPHEROID[\"Airy 1830\",6377563.396,299.32496460007]],
PRIMEM[\"Greenwich\",0],
UNIT[\"degrees\",0.0174532925199433]],
PROJECTION[\"Transverse_Mercator\"],
PARAMETER[\"Central_Meridian\",-2],
PARAMETER[\"False_Easting\",400000],
PARAMETER[\"False_Northing\",-100000],
PARAMETER[\"Latitude_of_Origin\",49],
PARAMETER[\"Scale_Factor\",0.9996012717],
UNIT[\"m\",1]]",
"cache": true,
"filter":"FEATURE_ID<10"
"readonly": true
}

Note: "cache" and "filter" are described in the Microsoft SQL Server Spatial (Dataset) topic.

It is strongly recommended to validate the JSON string (for example with JSONLint).

If a SQL Server connection has been built in the SIS desktop then all parameters can be gathered from the dataset properties.

Vector Product Format

clsDataSource = "VpfDts"
clsDataSource = "VpfDtsEx"

Parameter	Type	Comments
directory	String	Path to the folder containing LHT file
coverage	String	Name of coverage to add (as defined in the folder name)
lat	Integer	Centre latitude (degrees)
lon	Integer	Centre longitude (degrees)
width	Integer	Extents (degrees), Width (E/W)
height	Integer	Extents (degrees), Height (N/S)

The clsDataSource, "VpfDts", allows you to add an individual coverage. To load multiple coverages at once, use clsDataSource = "VpfDtsEx". It requires the same parameters as above as well as:

Parameter	Type	Comments
coverages	String	This is used instead of "coverage" listed above

NASA World Wind

clsDataSource = "WorldWindDataset"

Parameter	Type	Comments
name	String	Name of layer to add.
names	String	Used to add multiple layers at once. Use instead of "name"
LayerSplit	String	Define how multiple layers will split. Not required when adding single layer: "none" "layers" "overlays"

WCS

clsDataSource = "WCSDataSource"

Parameter	Type	Comments
url	String
coverage	String
showerrors	String	"true" "false"
user	String
password	String
connection	String	"dynamic" "import" "local"
forcegrid	String	"true" "false"
temporal	String	"true" "false"
defaultItemStatus	Integer	0 invisible 1 visible 2 hittable

OGC Web Feature Service

clsDataSource = "WFSDataSource"

Parameter	Type	Comments
getfeaturesuri	String
describefeaturesuri	String
describefeaturetypepostdata	String
postdata	String
overlayname	String
requestmethod	String	"post" "get"
validate	Boolean
showerrors	Boolean
username	String
password	String
defaultItemStatus	Integer	0 invisible 1 visible 2 hittable

See OGC WFS topic for a full description.

Example:

Dim params,strURL As String

strURL = "http://www.cadcorpdev.co.uk/wfs/SisISAPI.dll?request=GETFEATURE&;version=1.0.0&;server=WFS&;typename=EDINBURGH---6&;propertyname=EDINBURGH---6.GML_Geometry,EDINBURGH---6.Status"

params = "Getfeaturesuri=""" &; strURL &; """,validate=true"

GisCreateDataSourceOverlay (0, " WFSDataSource", params)

OGC Web Mapping Service

clsDataSource = "AOgcWmsDataset"

Parameter	Type	Comments
url	String
showerrors	Boolean
multi	String	"true" "false"
defaultItemStatus	Integer	0 invisible 1 visible 2 hittable
dynamic	Boolean
tiles	String
user	String
password	String
context	String

Example

Dim params,strURL As String

strURL="http://www.datasource.co.uk/wms/SisISAPI.dll?VERSION=1.1.0&;SERVICE=WMS&;REQUEST=GetMap&;STYLES=&;FORMAT=image/png&;SRS=EPSG:27700&;LAYERS=EDINBURGH&;BBOX=300000,650000,350000,700000&;WIDTH=1&;HEIGHT=1&;BGCOLOR=0xFFFFFF&;TRANSPARENT=TRUE&;EXCEPTIONS=application/vnd.ogc.se_xml"

params = "URL=""" &; strURL &; """,dynamic=true"

sis.CreateDataSourceOverlay (0, "AOgcWmsDataset", params)

OGC Web Map Tile Service

clsDataSource = "WMTSDataset"

Parameter	Type	Comments
URL	String
RequestType	Integer	0 GET 1 REST
LayerId	String
ImageFormat	String
TileMatrixSetId	String
ShowError	Boolean

The parameters should be passed as a JSON string. 

---

Available: GEO MD MM ME OD OM OV SISpy

Group:

• Overlay Methods
• Database Methods

---

Bing Maps, MapQuest, OS OpenSpace, Stamen

Data source classes shown in this section are available in all SIS products with UI:

ActiveX Control

Desktop SIS (MD, MM, ME), also via:

.NET GisLink API

Python in SIS:

Python GisLink API
Python API available in the Developer Control Bar

Data sources

1. BingMapsAerialTileDataset
2. BingMapsAerialWithLabelsTileDataset
3. BingMapsRoadTileDataset
4. MapQuestOSMTileDataset
5. MapQuestOpenAerialTileDataset
6. OSOpenSpaceProTileDataset
7. StamenTonerLiteTileDataset
8. StamenTonerTileDataset
9. StamenWatercolorTileDataset

These datasets do not require any parameters.

Bing Maps

Add overlay and SIS will prompt for the Bing Maps Application Key (see the screen shot below).

1: sis.CreateDataSourceOverlay(0, 'BingMapsAerialTileDataset', '')

2: sis.CreateDataSourceOverlay(0, 'BingMapsAerialWithLabelsTileDataset', '')

3: sis.CreateDataSourceOverlay(0, 'BingMapsRoadTileDataset', '')

Bing Maps prompts for an Application Key

Bing Maps - alternative method

To avoid seeing the Application Key prompt, set the system variable _BingMapsApplicationKey$ prior to the API call (see the screen shot below).

1: sis.SetProperty(sis.SIS_OT_SYSTEM, 0, '_BingMapsApplicationKey$', 'AoJ0BHy...m')

2: sis.CreateDataSourceOverlay(0, 'BingMapsAerialTileDataset', '')

Note: The Application Key number shown in Line 1 above is for example only you must use your own Application Key number.

Bing Maps does not request an Application Key

MapQuest

Add overlay and SIS will prompt for the Application Key

1. sis.CreateDataSourceOverlay(0, 'MapQuestOSMTileDataset', '')

2. sis.CreateDataSourceOverlay(0, 'MapQuestOpenAerialTileDataset', '')

Alternatively, set the system variable _MapQuestApplicationKey$, similar to the Bing Maps alternative method shown above.

OS OpenSpace

Add overlay and SIS will prompt for the Application Key (see the screen shot below).

1. sis.CreateDataSourceOverlay(0, 'OSOpenSpaceProTileDataset', '')

Alternatively, set the system variable _OSOpenSpaceProApplicationKey$, similar to the Bing Maps alternative method shown above.

OS OpenSpace prompts for an Application Key

Stamen

Add overlay and SIS will display the dataset (see the screen shot below).

1. sis.CreateDataSourceOverlay(0, 'StamenTonerLiteTileDataset', '')

2. sis.CreateDataSourceOverlay(0, 'StamenTonerTileDataset', '')

3. sis.CreateDataSourceOverlay(0, 'StamenWatercolorTileDataset', '')

No Application Key is required, so no system variables are provided.

Stamen does not require an Application Key

Available: GEO MD MM ME OD OM OV SISpy

Group:

• Overlay Methods
• Database Methods

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