org.geotools.filter
Class InterpolateFunction

java.lang.Object
  extended by org.geotools.filter.InterpolateFunction
All Implemented Interfaces:
org.opengis.filter.expression.Expression, org.opengis.filter.expression.Function

public class InterpolateFunction
extends java.lang.Object
implements org.opengis.filter.expression.Function

This is an implemenation of the Interpolate function as defined by OGC Symbology Encoding (SE) 1.1 specification.

The first parameter should be either the name of a numeric feature property or, if this function is being used as a raster colormap, the String "RasterData" (case-insensitive).

Following this there should be a sequence of interpolation points, each of which is described by two parameters: the first a datum and the second a return value. In the SE speicification these parameters are expected to be Literals but in this implementation more general Expressions are also supported.

Two optional parameters can be provided following the interpolation points: A "method" parameter which can take the values "numeric" or "color" and a "mode" parameter which can take the values "linear", "cosine" or "cubic" (Note: it would make more sense if these terms were reversed but we are adhering to their use as published in the OGC specification).

Number of points and interpolation modes