This element is used to configure the background maps to be displayed. The more advanced options are described below. Rather straightforward options like northArrowVisible are self explaining.
Optional description of the configuration. Used for reference purposes only.
The extents defined will appear in a drop down list in the toolbar above the map. Selecting an extent will change the view window of the map to the specified location.
Each extent contains the following attributes:
left, right, top, bottom: Coordinates of the zoom extent. Note that in displaying the maps for the extent defined, the map display will be scaled to fit the extent in the current display window.
Configuration of a geoDatum is important for the display of map layers in the FEWs Explorer and Grid display. A geoDatum is the coordinate system the extents, or map layers are defined in. Enumeration of of geoDatums of many different coordinate systems are available in Appendix B.
One can use various projections: mercator, web_mercator, orthographic, llxy and gnomonic. In combination with WMS services only (web-) mercator is possible.
Definition of the default zoom extent.
Definition of the additional zoom extents. Multiple entries may exist.
An example configuration containing two extents is shown below.
<geoDatum>WGS 1984</geoDatum> <defaultExtent id="my_defaultZoom" name="Default"> <left>96.38403320312536</left> <right>112.68774414062536</right> <top>1.8519463253148256</top> <bottom>-5.9482950514716</bottom> </defaultExtent> <extraExtent id="Indonesia" name="Indonesia"> <left>92</left> <right>141</right> <top>7</top> <bottom>-11</bottom> </extraExtent> |
For downloading layers from servers, sever different types of connections can be established.
Notice that you need to specify a mapLayersCacheDir in the global.properties, like mapLayersCacheDir=%REGION_HOME%/MapCache
More info on connection to ArcSDE and WFS can be found here.
Defines a Web Map Service (WMS) connection that can be referenced by a wmsLayer.
ArcSDE protocol is no longer supported in the map background layers. ESRI GeoServer supports the WFS protocol besides the ARCSDE protocol. The WFS protocol can still be used
Many different types of layers can be defined to be included in the map. All configured layers will be shown in the layer selection panel, where they can be turned on/off by the user. Some of these layers will be explained below.
Since 2013.01 FEWS enables using a compressed grid file for your DEM. The compression is done per scale and in tiles and archived in a zip file, pretty similar as openStreetMap works.
You can prepare a CTA (coverage tile archive) with the F12 menu in the explorer (F12 -> convert -> convert ascii grid to coverage tile archive).
As the resulting file should be in meters (see below why) you may need to specify a conversion factor from eg. centimeter to meter. You can also define an accuracy of the compressed values. Normally centimeter accuracy is more than enough, sometimes you can easily go to decimeters, which compresses much better of course. For synchronization reasons you may want to split the resulting file in parts of e.g. max 2 GB. Usually this is more than enough. The resulting compression is generally a factor of about 10-20. But the main reason is the much better performance of the GUI as per pixel is already determined which value should be plotted.
A very useful additional feature (to be used in the griddisplay only) is the feature that you can use the CTA as a real DEM and use it for plotting of water depths.
You then can easily display the water depths per pixel, based on a time series with water levels (using global datum!) and the DEM in the CTA. Therefore, enable the property useAsLocalDatumReference. Note, usesDatum in Parameters.xml for the respective parameterGroup should be set "true". The waterlevels can have any spatial distribution, like grid or polygon and should not have the exact same grid definition as the DEM. The calculation of the depths is completely on the fly and no depths have to be stored in the database.
<coverageTileArchiveLayer id="asc"> <file>petten.cta</file> <visible>false</visible> <useAsLocalDatumReference>false</useAsLocalDatumReference> <classBreaks> <lowerColor>brown</lowerColor> <upperColor>green</upperColor> <lowerValue>-4</lowerValue> lowerValue>-1</lowerValue> </classBreaks> </coverageTileArchiveLayer> |
<gridPlot id="Petten"> <timeSeriesSet> <moduleInstanceId>Floodmap</moduleInstanceId> <valueType>grid</valueType> <parameterId>H.sim.hist</parameterId> <locationId>Floodmap_grid</locationId> <timeSeriesType>simulated historical</timeSeriesType> <timeStep unit="minute" multiplier="1"/> <readWriteMode>read only</readWriteMode> </timeSeriesSet> <classBreaks> <break lowerValue="0" color="light blue" opaquenessPercentage="25"/> <break lowerValue="1" color="blue" opaquenessPercentage="75"/> <break lowerValue="2" color="purple" opaquenessPercentage="75"/> </classBreaks> <geoMap> <geoDatum>Rijks Driehoekstelsel</geoDatum> <projection>mercator</projection> <defaultExtent id="Petten testmodel"> <left>-1000</left> <right>10000</right> <top>4000</top> <bottom>0</bottom> </defaultExtent> <extraExtent id="Nederland"> <left>-200000</left> <right>500000</right> <top>750000</top> <bottom>200000</bottom> </extraExtent> <scaleBarVisible>true</scaleBarVisible> <northArrowVisible>true</northArrowVisible> <labelsVisible>true</labelsVisible> <backgroundColor>light blue1</backgroundColor> <openStreetMapLayer id="osm" name="Open Street Map"> <url>http://tile.openstreetmap.org</url> <cacheDir>$MAP_CACHE$/openstreetmaps</cacheDir> </openStreetMapLayer> <coverageTileArchiveLayer id="asc"> <file>petten.cta</file> <visible>false</visible> <useAsLocalDatumReference>true</useAsLocalDatumReference> <classBreaks> <lowerColor>brown</lowerColor> <upperColor>green</upperColor> <lowerValue>-4</lowerValue> <lowerValue>-1</lowerValue> </classBreaks> </coverageTileArchiveLayer> </geoMap> </gridPlot> |
With this layer a background shape file can be defined. This layer supports the common shape layer elements.
Other elements that can be used include:
An example of the various options, that can be completely mixed is shown in the below picture.
From version 2022.01 you can use a geoJSON files instead of shape files. When the geoJSON file contains multiple shape types you can use the same geoJSON file in multple layers with different types (options: point, line, polygon)
<geoJsonLayer id="geojson"> <file>provinces.geojson</file> <shapeType>polygon</shapeType> <visible>false</visible> <lineColor>black</lineColor> <fillColor>light yellow</fillColor> </geoJsonLayer> |
To make use of a server that uses the open street map protocol.
From version 2018.02 it has a standard copyright label in the right bottom corner. It needs no extra configuration and can't be turned off.
<openStreetMapLayer id="Osm"> <url>http://tile.openstreetmap.yourserver.com</url> <cacheDir>$REGION_HOME$/OsmTiles</cacheDir> </openStreetMapLayer> |
For testing purposes you can use "http://tile.openstreetmap.org"
To make use of a WMS server you have to use the option for wmsLayer.
You can request the capabilities of a WMS server by entering a url in your browser. The url you need to enter to do so is the base url of the server (anything before the '?' character) with "?request=GetCapabilities&service=WMS" added to it. For example, if your WMS server can be found at www.mywmsserver.com, the url you need to enter to request its capabilities is: www.mywmsserver.com?request=GetCapabilities&service=WMS
Some additional explanation for a few of the elements that can be configured for a <wmsLayer>:
Note that the wmsLayers configured in the geoMap will be used as a background layer and will not be animated over time. If you wish to show a wms layer that contains time series data, you should configure a <gridPlot> which contains a <wmsLayer> element for the layer instead. More information on configuring animated wms layers can be found on the Grid Display configuration page.
<wmsLayer id="meteosat"> <url>http://geoservices.knmi.nl/cgi-bin/METEOSAT9_DEMO.cgi?&SERVICE=WMS&</url> <geoDatum>EPSG:3857</geoDatum> <wmsLayerName>IR108</wmsLayerName> <cacheDir>$REGION_HOME$/wms_meteosat_cache</cacheDir> </wmsLayer> |
<wmsLayer id="srtm" name="SRTM Elevations"> <url>http://geoserver.webservice-energy.org/geoserver/mapserv/ows?</url> <geoDatum>EPSG:3857</geoDatum> <wmsLayerName>srtm</wmsLayerName> <visible>false</visible> <cacheDir>$CACHE_FOLDER$/WMSLayers/srtm</cacheDir> </wmsLayer> |
<wmsLayer id="ahn2"> <url>http://geodata.nationaalgeoregister.nl/ahn2/wms?service=wms&request=getcapabilities</url> <geoDatum>EPSG:3857</geoDatum> <wmsLayerName>ahn2_5m</wmsLayerName> <cacheDir>$REGION_HOME$/ahn2_5m</cacheDir> </wmsLayer> |
To make use of a Wfs or ArcSDE connection you have to use the option for serverShapeLayer. This layer supports the common shape layer elements.
Definition of a GIS layer to be displayed.
Attributes;
Elements:
description : Optional description of the map layer. Used for reference purposes only.
className : Name of the class used in displaying the map layer. A different class is required for different types of GIS data. NOTE: Defining a class name allows advanced users to add additional display functionality to the OpenMap utility, and this being used in map displays in DELFT-FEWS. See the OpenMap documentation for details on how to add additional display classes.
visible : Boolean flag indicating if layer is visible by default.
properties : Definition of properties associated with the map layer to be displayed. Properties that need to be defined depend on the class used. At least one property must be defined. This may be a dummy property. Multiple entries may exist.
Some additional information on the elements that can be defined in properties:
Value : Value of the property defined.
Note: when displaying a shape file layer that does not use WGS 1984 as the coordinate system, a property must be defined that defines the geo datum. To do this set the key value as "geoDatum" and define the coordinate system using the enumeration in Appendix B.
See some examples of nice tile layers below. See also http://server.arcgisonline.com/ArcGIS/rest/services/
<layer id="World" name="ArcGIS World_Topo_Map"> <className>nl.wldelft.libx.openmap.GenericTileServerLayer</className> <properties> <string key="tileUrlPattern" value="http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer/tile/%ZOOM%/%ROW%/%COLUMN%"/> <string key="cacheDir" value="%REGION_HOME%/mapcache/Esri_topo"/> <int key="minZoomLevel" value="1"/> <int key="maxZoomLevel" value="19"/> <int key="topZoomLevel" value="21"/> <int key="tileSize" value="256"/> </properties> </layer> <layer id="Canvas" name="ArcGIS Canvas World_Light_Gray_Base"> <className>nl.wldelft.libx.openmap.GenericTileServerLayer</className> <properties> <string key="tileUrlPattern" value="http://server.arcgisonline.com/arcgis/rest/services/Canvas/World_Light_Gray_Base/MapServer/tile/%ZOOM%/%ROW%/%COLUMN%"/> <string key="cacheDir" value="%REGION_HOME%/mapcache/Esri_Canvas_World_Light_Gray_Base"/> <int key="minZoomLevel" value="1"/> <int key="maxZoomLevel" value="19"/> <int key="topZoomLevel" value="21"/> <int key="tileSize" value="256"/> </properties> </layer> <openStreetMapLayer id="Osm" name="Open Street Map"> <url>http://tile.openstreetmap.org</url> <cacheDir>$REGION_HOME$/OsmTiles</cacheDir> </openStreetMapLayer> <openStreetMapLayer id="Osm" name="Open Street Map (Toner)"> <url>http://tile.stamen.com/toner</url> <cacheDir>$REGION_HOME$/mapcache/stamen_toner</cacheDir> </openStreetMapLayer> |
These elements are supported for both the serverShapeLayer and the esriShapeLayer:
selectByMapItemLocationRelation: When this element is specified an location relation is used to find locations at the map instead of the polygon border.
selectByMapItemAttributeEquals: When this element is specified a (multivalued) location attribute is used to find locations at the map instead of the polygon border.
An example for color classification based on attributes is shown below. Notice that all possible values need to be included.
<esriShapeLayer id="WS Indonesia"> <file>ws_indonesia</file> <geoDatum>WGS 1984</geoDatum> <visible>true</visible> <toolTip>%WS%</toolTip> <lineColor>gray</lineColor> <classBreaksAttributeName>Balai</classBreaksAttributeName> <classBreaks> <break lowerValue="0" label="BWS Sulawesi II" color="aquamarine1"/> <break lowerValue="1" label="BWS Papua" color="purple2"/> <break lowerValue="2" label="BWS Maluku" color="red1"/> </classBreaks> </esriShapeLayer> |
Since 2017.02 several label formatting elements are supported:
An example for a label configuration is shown below.
<esriShapeLayer id="myPrettyLabelLayer"> <file>layerFile</file> <label>%labelColumn%</label> <labelFontSize>15</labelFontSize> <labelFontColor>blue</labelFontColor> <labelBackgroundColor>red</labelBackgroundColor> <labelOpaqueness>20</labelOpaqueness> <labelBorderColor>black</labelBorderColor> <labelXAttribute>labelXColumn</labelXAttribute> <labelYAttribute>labelYColumn</labelYAttribute> <lineColor>gray90</lineColor> <fillColor>yellow</fillColor> <opaquenessPercentage>25</opaquenessPercentage> </esriShapeLayer> |
Since 2017.02 for shape-layers containing points, class breaks are allowed to use icons instead of colors. If both class breaks containing icons and a pointIconId is specified, the pointIconId is used as a default when no class break applies. It is also used in the image displayed before the layer name in the layer selection panel. Note that this image will only be loaded if the layer has been loaded, i.e., was ever visible during the current session. A config example is shown below.
<esriShapeLayer id="myPointLayer" name="Some Points"> <file>myPointLayer.shp</file> <pointIconId>default_icon.gif</pointIconId> <classBreaksAttributeName>ICON_ATTRIBUTE</classBreaksAttributeName> <classBreaks> <break lowerValue="0" label="low" icon="green_circle.gif"/> <break lowerValue="1000" label="high" icon="blue_square.gif"/> </classBreaks> </esriShapeLayer> |
<geoMap> <geoDatum>WGS 1984</geoDatum> <projection>orthographic</projection> <defaultExtent id="NW halfrond"> <left>-90</left> <right>5</right> <top>90</top> <bottom>0</bottom> </defaultExtent> <extraExtent id="Europa"> <left>-2</left> <right>25</right> <top>75</top> <bottom>30</bottom> </extraExtent> <extraExtent id="Nederland"> <left>2</left> <right>6</right> <top>54</top> <bottom>50</bottom> </extraExtent> <scaleBarVisible>true</scaleBarVisible> <northArrowVisible>true</northArrowVisible> <labelsVisible>true</labelsVisible> <backgroundColor>dark slate blue</backgroundColor> <esriShapeLayer id="World"> <file>cntry98</file> <geoDatum>WGS 1984</geoDatum> <visible>true</visible> <lineColor>black</lineColor> <fillColor>dark olive green</fillColor> </esriShapeLayer> <gridLayer/> <esriShapeLayer id="World (overlay)"> <file>cntry98</file> <geoDatum>WGS 1984</geoDatum> <visible>true</visible> <lineColor>black</lineColor> <opaquenessPercentage>0</opaquenessPercentage> </esriShapeLayer> </geoMap> |
The above config example of using a orthographic projection will result in the below picture. In this picture the GFS precipitation forecast is combined with isolines of airpressure.