Package com.jhlabs.image

Class Gradient

java.lang.Object
com.jhlabs.image.ArrayColormap
com.jhlabs.image.Gradient
All Implemented Interfaces:
Colormap, Cloneable
public class Gradient extends ArrayColormap implements Cloneable
A Colormap implemented using Catmull-Rom colour splines. The map has a variable number of knots with a minimum of four. The first and last knots give the tangent at the end of the spline, and colours are interpolated from the second to the second-last knots. Each knot can be given a type of interpolation. These are:
  • LINEAR - linear interpolation to next knot
  • SPLINE - spline interpolation to next knot
  • CONSTANT - no interpolation - the colour is constant to the next knot
  • HUE_CW - interpolation of hue clockwise to next knot
  • HUE_CCW - interpolation of hue counter-clockwise to next knot

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    CIRCLE_DOWN
    Interpolate with a falling circle shape curve.
    static final int
    CIRCLE_UP
    Interpolate with a rising circle shape curve.
    static final int
    CONSTANT
    Don't tnterpolate - just use the starting value.
    static final int
    HUE_CCW
    Interpolate hue counter clockwise.
    static final int
    HUE_CW
    Interpolate hue clockwise.
    static final int
    LINEAR
    Interpolate linearly.
    static final int
    RGB
    Interpolate in RGB space.
    static final int
    SPLINE
    Interpolate using a spline.

    Fields inherited from class com.jhlabs.image.ArrayColormap

    map

  • Constructor Summary

    Constructors
    Constructor
    Description
    Gradient()
    Construct a Gradient.
    Gradient(int[] rgb)
    Construct a Gradient with the given colors.
    Gradient(int[] x, int[] rgb)
    Construct a Gradient with the given colors and knot positions.
    Gradient(int[] x, int[] rgb, byte[] types)
    Construct a Gradient with the given colors, knot positions and interpolation types.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    addKnot(int x, int color, int type)
    Add a new knot.
    Object
    clone()
     
    void
    copyTo(Gradient g)
    Copy one Gradient into another.
    int
    getKnot(int n)
    Get a knot color.
    byte
    getKnotBlend(int n)
    Get a knot blend type.
    int
    getKnotPosition(int n)
    Get a knot position.
    int
    getKnotType(int n)
    Get a knot type.
    int
    getNumKnots()
    Get the number of knots in the gradient.
    int
    knotAt(int x)
    Return the knot at a given position.
    void
    mutate(float amount)
    Mutate the gradient.
    static Gradient
    randomGradient()
    Build a random gradient.
    void
    randomize()
    Randomize the gradient.
    void
    removeKnot(int n)
    Remove a knot.
    void
    setColor(int n, int color)
    Set a knot color.
    void
    setKnot(int n, int color)
    Set a knot color.
    void
    setKnotBlend(int n, int type)
    Set a knot blend type.
    void
    setKnotPosition(int n, int x)
    Set a knot position.
    void
    setKnots(int[] x, int[] rgb, byte[] types)
    Set the values of all the knots.
    void
    setKnots(int[] x, int[] y, byte[] types, int offset, int count)
    Set the values of a set of knots.
    void
    setKnotType(int n, int type)
    Set a knot type.
    void
    splitSpan(int n)
    Split a span into two by adding a knot in the middle.

    Methods inherited from class com.jhlabs.image.ArrayColormap

    getColor, getMap, setColorInterpolated, setColorRange, setColorRange, setMap

    Methods inherited from class java.lang.Object

    equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • RGB

      public static final int RGB
      Interpolate in RGB space.
      See Also:

    • HUE_CW

      public static final int HUE_CW
      Interpolate hue clockwise.
      See Also:

    • HUE_CCW

      public static final int HUE_CCW
      Interpolate hue counter clockwise.
      See Also:

    • LINEAR

      public static final int LINEAR
      Interpolate linearly.
      See Also:

    • SPLINE

      public static final int SPLINE
      Interpolate using a spline.
      See Also:

    • CIRCLE_UP

      public static final int CIRCLE_UP
      Interpolate with a rising circle shape curve.
      See Also:

    • CIRCLE_DOWN

      public static final int CIRCLE_DOWN
      Interpolate with a falling circle shape curve.
      See Also:

    • CONSTANT

      public static final int CONSTANT
      Don't tnterpolate - just use the starting value.
      See Also:

  • Constructor Details

    • Gradient

      public Gradient()
      Construct a Gradient.

    • Gradient

      public Gradient(int[] rgb)
      Construct a Gradient with the given colors.
      Parameters:
      rgb - the colors

    • Gradient

      public Gradient(int[] x, int[] rgb)
      Construct a Gradient with the given colors and knot positions.
      Parameters:
      x - the knot positions
      rgb - the colors

    • Gradient

      public Gradient(int[] x, int[] rgb, byte[] types)
      Construct a Gradient with the given colors, knot positions and interpolation types.
      Parameters:
      x - the knot positions
      rgb - the colors
      types - interpolation types

  • Method Details

    • clone

      public Object clone()
      Overrides:
      clone in class ArrayColormap

    • copyTo

      public void copyTo(Gradient g)
      Copy one Gradient into another.
      Parameters:
      g - the Gradient to copy into

    • setColor

      public void setColor(int n, int color)
      Set a knot color.
      Overrides:
      setColor in class ArrayColormap
      Parameters:
      n - the knot index
      color - the color
      See Also:

    • getNumKnots

      public int getNumKnots()
      Get the number of knots in the gradient.
      Returns:
      the number of knots.

    • setKnot

      public void setKnot(int n, int color)
      Set a knot color.
      Parameters:
      n - the knot index
      color - the color
      See Also:

    • getKnot

      public int getKnot(int n)
      Get a knot color.
      Parameters:
      n - the knot index
      Returns:
      the knot color
      See Also:

    • setKnotType

      public void setKnotType(int n, int type)
      Set a knot type.
      Parameters:
      n - the knot index
      type - the type
      See Also:

    • getKnotType

      public int getKnotType(int n)
      Get a knot type.
      Parameters:
      n - the knot index
      Returns:
      the knot type
      See Also:

    • setKnotBlend

      public void setKnotBlend(int n, int type)
      Set a knot blend type.
      Parameters:
      n - the knot index
      type - the knot blend type
      See Also:

    • getKnotBlend

      public byte getKnotBlend(int n)
      Get a knot blend type.
      Parameters:
      n - the knot index
      Returns:
      the knot blend type
      See Also:

    • addKnot

      public void addKnot(int x, int color, int type)
      Add a new knot.
      Parameters:
      x - the knot position
      color - the color
      type - the knot type
      See Also:

    • removeKnot

      public void removeKnot(int n)
      Remove a knot.
      Parameters:
      n - the knot index
      See Also:

    • setKnots

      public void setKnots(int[] x, int[] rgb, byte[] types)
      Set the values of all the knots. This version does not require the "extra" knots at -1 and 256
      Parameters:
      x - the knot positions
      rgb - the knot colors
      types - the knot types

    • setKnots

      public void setKnots(int[] x, int[] y, byte[] types, int offset, int count)
      Set the values of a set of knots.
      Parameters:
      x - the knot positions
      y - the knot colors
      types - the knot types
      offset - the first knot to set
      count - the number of knots

    • splitSpan

      public void splitSpan(int n)
      Split a span into two by adding a knot in the middle.
      Parameters:
      n - the span index

    • setKnotPosition

      public void setKnotPosition(int n, int x)
      Set a knot position.
      Parameters:
      n - the knot index
      x - the knot position
      See Also:

    • getKnotPosition

      public int getKnotPosition(int n)
      Get a knot position.
      Parameters:
      n - the knot index
      Returns:
      the knot position
      See Also:

    • knotAt

      public int knotAt(int x)
      Return the knot at a given position.
      Parameters:
      x - the position
      Returns:
      the knot number, or 1 if no knot found

    • randomize

      public void randomize()
      Randomize the gradient.

    • mutate

      public void mutate(float amount)
      Mutate the gradient.
      Parameters:
      amount - the amount in the range zero to one

    • randomGradient

      public static Gradient randomGradient()
      Build a random gradient.
      Returns:
      the new Gradient