RasterSymbolizer

RasterSymbolizer is used to draw a geo-referenced raster image (e.g. satellite image, scanned historical maps, etc.) or terrain elevation data (e.g. DEM) as shaded relief.

Parameter NameValue TypeDescriptionRequired
ColorMapColorMapSpecifies a continuous palette of colors to colorize an elevation map.No
CompositingModeCompositingModeSpecifies how the raster image is combined with the canvas. Default value is SourceOver.No
ImageOutlineSymbolizerSpecifiews whether and how the raster image should be outlined. Possible values are either LineSymbolizer or PolygonSimbolizer.No
InterpolationModeInterpolationModeSpecifies the algorithm that is used when images are scaled or rotated. This parameter is taken into account when Scale is not equal 1.No
OpacitySingleSpecifies the opacity of the image when it is combined with the background.No
ShadedReliefShadedReliefSpecifies whether and how relief shading is applied to an image.No

ColorMap

ColorMap element defines a set of control points, called ColorMapEntry, which are used to colorize an elevation map. Each ColorMapEntry element specifies the color and the quantity value, which is altitude of elevation. In hillshading, the color of each elevation point is computed using linear interpolation between two color map entries with altitudes above and below the given value.

The following examples demonstrates a ColorMap to produce a shaded relief given below.

<ColorMap>
  <ColorMapEntry>
    <Color>#A3BDE0</Color>
    <Label />
    <Quantity>0</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>#C7DAA5</Color>
    <Quantity>1</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>#DEE5C3</Color>
    <Quantity>200</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>#B9CFB5</Color>
    <Quantity>1000</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>#71BF7E</Color>
    <Quantity>2500</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>#C18E39</Color>
    <Quantity>3500</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
  <ColorMapEntry>
    <Color>White</Color>
    <Quantity>4200</Quantity>
    <Opacity>1</Opacity>
  </ColorMapEntry>
</ColorMap>

ShadedRelief

ShadedRelief allows to set parameters of hillshading.

Parameter NameValue TypeDescriptionRequired
BrightnessOnlyBooleanSpecifies whether the shading is applied using color or only alpha component. Default value is False.No
CustomShadingMethodStringSpecifies the name of a custom shading method which can be implemented as a plugin.No
MaximumSingleSpecifies the maximum altitude of elevation. Default value is 8848.No
MinimumSingleSpecifies the minimum altitude of elevation. Default value is 0.No
ShaderTypeShaderTypeSpecifies the type of a ColorMap. The Custom value means that user-defined ColorMap will be used. Default value is Jet.No
ShadingMethodShadingMethodThe custom value means that CustomShadingMethod is used. Default value is StandardCombined.No
ShadingParametersShadingParametersSpecifies the shading parameters such as sun altitude, sun azimuth or scale.No

ShaderType

The list of pre-defined shader types is:

  • Jet
  • Cool
  • Gray
  • LightGray
  • Bone
  • Pink
  • Copper
  • Hot
  • HSV
  • Summer
  • Autumn
  • Winter
  • Spring
  • Rock
  • Surface
  • LightSurface
  • Blast
  • Gold
  • Custom

ShadingMethod

The list of pre-defined shading methods is:

  • Aspect
  • ErdasAspect
  • ErdasSlope
  • HornSlope
  • Standard
  • StandardCombined
  • ZevenbergenThorne
  • ZevenbergenThorneAspect
  • ZevenbergenThorneCombined
  • ZevenbergenThorneSlope
  • Custom

ShadingParameters

Parameter NameValue TypeDescriptionRequired
ScaleSingleSpecifies the ratio of vertical units to horizontal. Default value is 1.No
SunAltitudeSingleSpecifies the altitude of the light source, in degrees. Default value is 45.No
SunAzimuthSingleSpecifies the azimuth of the light source, in degrees. Default value is 315.No
ZScaleFactorSingleSpecifies additional scale factor. Default value is 1.No