Package org.geotools.gce.grassraster.core.color

Class JGrassColorTable

Object
JGrassColorTable
public class JGrassColorTable extends Object
Represents a GRASS rastermap color table.

Colortables for GRASS 5 and greater are supported.

Format of the color file, which is located in location/mapset/colr/mapname:

The first line is a % character and two numbers indicating the minimum and maximum data values which have colors. Note that in JGrass after the range values we add a third value for alpha support.

After the first line, the list of color rules appears, that can be of the following formats:

  • value1:r:g:b value2:r:g:b interpolation of colors between the two values with the two colors
  • value1:grey value2:grey </code interpolation of grayscale between the two values with the two grey values>
  • value1:r:g:b assumption that it means that value1 == value2
  • nv:r:g:b novalues could also have color with such a rule.
Since:
3.0
Author:
Andrea Antonello (www.hydrologis.com)

  • Constructor Details

    • JGrassColorTable

      public JGrassColorTable(JGrassMapEnvironment readerGrassEnv, double[] dataRange) throws IOException
      Creates a new instance of ColorTable
      Parameters:
      readerGrassEnv - the grass environment used to identify paths.
      dataRange - the datarange to be used if the native one is missing.
      Throws:
      IOException

  • Method Details

    • createDefaultColorTable

      public static List<String> createDefaultColorTable(double[] dataRange, int alpha)
      Creates a default rainbow color table given a data range.
      Parameters:
      dataRange - the data range for which the color table is created
      Returns:
      the list of color rules as value1:r:g:b value2:r:g:b alpha

    • getColorRules

      public List<String> getColorRules()
      Getter for the color rules.
      Returns:
      the list of color rules.

    • getAlpha

      public int getAlpha()
      Getter for the alpha value.
      Returns:
      the alpha value.

    • parseColorRule

      public static void parseColorRule(String rule, double[] values, Color[] colors)
      parses a color rule.

      Arrays of doubles and colors have to be passed, that will be filled with the values of the color rule.

      Parameters:
      rule - the color rule as taken from the list returned by getColorRules()
      values - the array of doubles to be filled with the values.
      colors - the array of Color to be filled with the colors (can be null).