Raster map package

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This page contains documentation on the parameters and names which make up a raster map packages xml file.

Datasets are evaluated from top to bottom in the xml-file, so if you have multiple datasets that cover the same area and scale/resolution range, the last dataset will cover the first.

Example XML's

The raster map packages file should be named .rastermappackages.xml or (versions post 2.0.1) .rastermappackage.xml. The latter is equivalent to .m6mmappackage.xml for vector maps and contains only one mappackage where as the .rastermappackages.xml can contain multiple mappackages.

All elements and attributes in the xml-files should be lowercase unless otherwise noted.

Example rastermappackages.xml:

<mappackages>
  
  <mappackage signature="Oslo">
    <rasterdataref id="Blue Marble"/>
    <rasterdataref id="Oslo Raster"/>
  </mappackage>
  
  <mappackage signature="GMTED2010">
    <params>
      <param name="mapContentType" value="Elevation"/>
    </params>
    <rastermapdataset id="GMTED 2010">
      <dataset path="Raster\GMTED2010\GMTED2010.vrt"/>
    </rastermapdataset>
  </mappackage>
  
  <mappackage signature="N50">
    <rastermapdataset>
      <dataset dir="Raster\N50\utm33"  extension=".qm2"/>
      <params>
    <param name="proj4" value="+proj=utm +zone=33 +datum=WGS84"/>
    <param name="resampleMethod" value="Bilinear"/>
    <param name="minScale" value="5000"/>
    <param name="maxScale" value="50000"/>
      </params>
    </rastermapdataset>
  </mappackage>
  
  <mappackage signature="NormalMapElevations" name="Normal map elevation data">
    <params>
      <param name="resampleMethod" value="Bilinear"/>
      <param name="mapContentType" value="ElevationNormals"/>
    </params>
    <rastermapdataset>
      <dataset path="Raster\dted2\dted2no.vrt"/>
      <params>
        <param name="minResolution" value="250"/>
      </params>
    </rastermapdataset>
    <rastermapdataset>
      <dataset path="Raster\SRTM30\SRTM30.vrt"/>
      <params>
        <param name="maxResolution" value="250"/>
      </params>
    </rastermapdataset>
  </mappackage>
  
</mappackages>

Example rastermappackage.xml (versions newer than 2.0.1):

<mappackage signature="NE2_HR_87a0eec4-0fe3-48cc-84f6-38bf9d0f755b" name="NE_background">
   
   <rastermapdataset id="NE_background">
      <dataset path="Data\NE2_HR_LC_SR_W.tif.gpkg" recursive="false" />
   </rastermapdataset>
   <params>
     <param name="projection" value="native" />
   </params>
   
</mappackage>

Mappackages

<mappackages> is the root of the mappackages-xml and acts as a container for one or more map packages. In mappackage-xml's, with only one map package, <mappackage> is the root element.

Child element Description Properties
mappackage Raster dataset container. O R C

Mappackage

A mappackage is a collection of parameters and datasets.

Child element Description Properties
Collection of mappackage parameters. O C
A collection of raster datasets. O R C A
A reference to a rastermapdataset O R A
Obsolete
Attribute Description Properties
signature A unique name that identifies a map package.

Params

Child element Description Properties
Map package parameter. F.ex. surface type, resample method, map content type etc. O R A
Param
Attribute Description Properties
name Parameter name.
value Parameter value.

Valid parameters are:

Attribute Description Properties
proj4 Projection string in PROJ4 format. Overrides any projection info in the data files. A list of map projections and their corresponding proj4/WKT strings can be found at spatialreference.org
projWKT Projection string in WKT format. Overrides any projection info in the data files. A list of map projections and their corresponding proj4/WKT strings can be found at spatialreference.org
minResolution Minimum valid resolution in units per pixel for this dataset, for example meters/pixel or degrees/pixel. Requesting an image with lower resolution will give an "OutsideResolution" result unless another dataset covers the same area with lower resolution.
maxResolution Maximum valid resolution in units per pixel for this dataset. Requesting an image with higher resolution will give an "OutsideResolution" result unless another dataset covers the same area with higher resolution.
minScale Minimum valid (nominal) scale for this dataset. Requesting an image with lower scale (more detail) will give an OutsideResolution result unless another dataset covers the same area with lower minScale.
maxScale Maximum valid (nominal) scale for this dataset. Requesting an image with higher scale (less detail) will give an OutsideResolution result unless another dataset covers the same area with higher maxScale.
resampleMethod Resampling method. Valid values are: "NearestNeighbour" (default), "Bilinear", "Cubic", "CubicSpline" and "Lanczos".
mapContentType Intended usage of the raster data. If not given, a regular raster map is assumed. Other values can be "Elevation" for elevation data or "ElevationNormals" for normal maps used for shading.
nodata Nodata value. For elevation data, samples equal to this value are ignored when assembling the output image. For paletted images, pixels with this palette index are treated as transparent. This value is not used for RGBA images which instead uses the alpha channel for transparency, or transparentColor.
transparentColor RGBA color to treat as transparent. This is used as "nodata" for RGBA color data sets. The value should be given as a hex color string in RGBA order, i.e #RRGGBBAA, for example "#ffffffff" for full white.
transparentTolerance Tolerance for transparent color comparisons. In some cases you may want to mask away a certain color and colors that are close to it. This value indicates how much a color can differ from the transparent color (by component) and still be considered transparent. For example, if the transparent color is "#ffffffff" an tolerance is 1, both #fefefefe" and #fffffffe" will also be considered transparent
subDataId For data with subdatasets this indicates the index of the subdataset we want to use. If not given, all subdatasets are used. The ID is an integer in the region 1-N where N is the number of subdatasets.
subDataList For data with subdatasets this indicates a comma-separated list of subdatasets we want to use. If not given, all subdatasets are used. The ID is an integer in the region 1-N where N is the number of subdatasets.
projection This parameter can be given on map package level to indicate the preferred projection of this dataset(s). It can be either a WKT or an EPSG code. You can also set this to "native" which will give you the native projection of the datasets (if the data sets have different projections, the first suitable projection is used.)
scaleFactor A float value to scale the elevation data, and will scale all datasets in the map package. If no scaleFactor is given on map package-level, it can be set as an parameter one or more of the datasets.
elevationDataType Type of elevation data. Valid values are "TerrainModel", "SurfaceModel", "Bathymetry".
tags Generic tag which can match the map signature to a dataprovider. This is used for Color map layers in templates.

Rastermapdataset

A raster map dataset defines a set of files with common parameters. Typically a map signature can consist of different datasets at different scale or resolution ranges.

Child element Description Properties
Raster map dataset. O R A
Dataset parameters. O C
Attribute Description Properties
id String identifying this rastermapdataset. Used when referencing a dataset from another mappackage.
Dataset
Attribute Description Properties
path Path to dataset. Path can be absolute or relative.
dir Dataset directory.
extension File extension. Used with dir attribute. Note that this parameter is case sensitive
recursive Recursive file search. Used with dir attribute. Valid values are true/false.
Param
Attribute Description
scaleFactor A float value to scale the elevetation data it the dataset. NOTE: Requires that no scaleFactor parameter is given on map package-level.

Rasterdataref

Attribute Description Properties
id String identifying a rastermapdataset. O

Revisions

Obsolete.

General tips and notes

  • For high resolution data sets without overviews or low resolution pyramids, make sure to set up limits on the maxScale or minResolution. If not, the server will try to read the entire data set when you request a map that is zoomed far out.
  • Use Bilinear resampling on imagery for good looking results.
  • Generate overviews if your rasterdata is to be used in lower resolution than the original data.