Module javafx.graphics

Package javafx.scene.paint

Class RadialGradient

java.lang.Object

javafx.scene.paint.Paint

javafx.scene.paint.RadialGradient

public final class RadialGradient
extends Paint

The RadialGradient class provides a way to fill a shape with a circular radial color gradient pattern. The user may specify 2 or more gradient colors, and this paint will provide an interpolation between each color.

The user must specify the circle controlling the gradient pattern, which is defined by a center point and a radius. The user can also specify a separate focus point within that circle, which controls the location of the first color of the gradient. By default the focus is set to be the center of the circle.

The center and radius are specified relative to a unit square, unless the proportional variable is false. By default proportional is true, and the gradient will be scaled to fill whatever shape it is applied to. The focus point is always specified relative to the center point by an angle and a distance relative to the radius.

This paint will map the first color of the gradient to the focus point, and the last color to the perimeter of the circle, interpolating smoothly for any in-between colors specified by the user. Any line drawn from the focus point to the circumference will thus span all of the gradient colors.

The focus distance will be clamped to the range (-1, 1) so that the focus point is always strictly inside the circle.

The application provides an array of Stops specifying how to distribute the colors along the gradient. The Stop#offset variable must be the range 0.0 to 1.0 and act like keyframes along the gradient. They mark where the gradient should be exactly a particular color.

Since:

JavaFX 2.0

Constructor Summary

Constructors

Constructor	Description
RadialGradient(double focusAngle, double focusDistance, double centerX, double centerY, double radius, boolean proportional, CycleMethod cycleMethod, List<Stop> stops)	Creates a new instance of RadialGradient.
RadialGradient(double focusAngle, double focusDistance, double centerX, double centerY, double radius, boolean proportional, CycleMethod cycleMethod, Stop... stops)	Creates a new instance of RadialGradient.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object obj)	Indicates whether some other object is "equal to" this one.
double	getCenterX()	Defines the X coordinate of the center point of the circle defining the gradient.
double	getCenterY()	Defines the X coordinate of the center point of the circle defining the gradient.
CycleMethod	getCycleMethod()	Defines the cycle method applied to the RadialGradient.
double	getFocusAngle()	Defines the angle in degrees from the center of the gradient to the focus point to which the first color is mapped.
double	getFocusDistance()	Defines the distance from the center of the gradient to the focus point to which the first color is mapped.
double	getRadius()	Specifies the radius of the circle defining the extents of the color gradient.
List<Stop>	getStops()	A sequence of 2 or more Stop values specifying how to distribute the colors along the gradient.
int	hashCode()	Returns a hash code for this RadialGradient object.
boolean	isOpaque()	Gets whether this Paint is completely opaque.
boolean	isProportional()	Indicates whether the center and radius values are proportional or absolute.
String	toString()	Returns a string representation of this RadialGradient object.
static RadialGradient	valueOf(String value)	Creates a radial gradient value from a string representation.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

RadialGradient

public RadialGradient(double focusAngle,
                      double focusDistance,
                      double centerX,
                      double centerY,
                      double radius,
                      boolean proportional,
                      CycleMethod cycleMethod,
                      Stop... stops)

Creates a new instance of RadialGradient.

Parameters:

focusAngle - the angle in degrees from the center of the gradient to the focus point to which the first color is mapped

focusDistance - the distance from the center of the gradient to the focus point to which the first color is mapped

centerX - the X coordinate of the center point of the gradient's circle

centerY - the Y coordinate of the center point of the gradient's circle

radius - the radius of the circle defining the extents of the color gradient

proportional - whether the coordinates and sizes are proportional to the shape which this gradient fills

cycleMethod - cycle method applied to the gradient

stops - the gradient's color specification

RadialGradient

public RadialGradient(double focusAngle,
                      double focusDistance,
                      double centerX,
                      double centerY,
                      double radius,
                      boolean proportional,
                      CycleMethod cycleMethod,
                      List<Stop> stops)

Creates a new instance of RadialGradient.

Parameters:

focusAngle - the angle in degrees from the center of the gradient to the focus point to which the first color is mapped

focusDistance - the distance from the center of the gradient to the focus point to which the first color is mapped

centerX - the X coordinate of the center point of the gradient's circle

centerY - the Y coordinate of the center point of the gradient's circle

radius - the radius of the circle defining the extents of the color gradient

proportional - whether the coordinates and sizes are proportional to the shape which this gradient fills

cycleMethod - cycle method applied to the gradient

stops - the gradient's color specification

Method Detail

getFocusAngle

public final double getFocusAngle()

Defines the angle in degrees from the center of the gradient to the focus point to which the first color is mapped.

Returns:

the angle in degrees from the center of the gradient to the focus point to which the first color is mapped

getFocusDistance

public final double getFocusDistance()

Defines the distance from the center of the gradient to the focus point to which the first color is mapped. A distance of 0.0 will be at the center of the gradient circle. A distance of 1.0 will be on the circumference of the gradient circle.

Returns:

the distance from the center of the gradient to the focus point to which the first color is mapped

getCenterX

public final double getCenterX()

Defines the X coordinate of the center point of the circle defining the gradient. If proportional is true (the default), this value specifies a point on a unit square that will be scaled to match the size of the the shape that the gradient fills. The last color of the gradient is mapped to the perimeter of this circle.

Default value:

0.0

Returns:

the X coordinate of the center point of the circle defining the gradient

getCenterY

public final double getCenterY()

Defines the X coordinate of the center point of the circle defining the gradient. If proportional is true (the default), this value specifies a point on a unit square that will be scaled to match the size of the the shape that the gradient fills. The last color of the gradient is mapped to the perimeter of this circle.

Default value:

0.0

Returns:

the X coordinate of the center point of the circle defining the gradient

getRadius

public final double getRadius()

Specifies the radius of the circle defining the extents of the color gradient. If proportional is true (the default), this value specifies a size relative to unit square that will be scaled to match the size of the the shape that the gradient fills.

Default value:

1.0

Returns:

the radius of the circle defining the extents of the color gradient

isProportional

public final boolean isProportional()

Indicates whether the center and radius values are proportional or absolute. If this flag is true, the center point and radius are defined in a coordinate space where coordinates in the range [0..1] are scaled to map onto the bounds of the shape that the gradient fills. If this flag is false, then the center coordinates and the radius are specified in the local coordinate system of the node.

Default value:

true

Returns:

true if the center and radius values are proportional, otherwise absolute

getCycleMethod

public final CycleMethod getCycleMethod()

Defines the cycle method applied to the RadialGradient. One of: CycleMethod.NO_CYCLE, CycleMethod.REFLECT, or CycleMethod.REPEAT.

Default value:

NO_CYCLE

Returns:

the cycle method applied to this radial gradient

getStops

public final List<Stop> getStops()

A sequence of 2 or more Stop values specifying how to distribute the colors along the gradient. These values must be in the range 0.0 to 1.0. They act like keyframes along the gradient: they mark where the gradient should be exactly a particular color.

Each stop in the sequence must have an offset that is greater than the previous stop in the sequence.

The list is unmodifiable and will throw UnsupportedOperationException on each modification attempt.

Default value:

empty

Returns:

the list of Stop values

isOpaque

public final boolean isOpaque()

Gets whether this Paint is completely opaque. An opaque paint is one that has no alpha component in any of its colors. It may be possible for a Paint to be opaque and yet return false, if it cannot be easily determined whether the paint is actually opaque. For example, the ImagePattern may not be able to cheaply determine its opacity.

Specified by:

isOpaque in class Paint

Returns:

true if the Paint is opaque, false if it is not opaque or if it cannot be determined.

Since:

JavaFX 8.0

equals

public boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if this object is equal to the obj argument; false otherwise.

hashCode

public int hashCode()

Returns a hash code for this RadialGradient object.

Overrides:

hashCode in class Object

Returns:

a hash code for this RadialGradient object.

toString

public String toString()

Returns a string representation of this RadialGradient object.

Overrides:

toString in class Object

Returns:

a string representation of this RadialGradient object.

valueOf

public static RadialGradient valueOf(String value)

Creates a radial gradient value from a string representation.

The format of the string representation is based on JavaFX CSS specification for radial gradient which is

 radial-gradient([focus-angle <angle>, ]?
                 [focus-distance <percentage>, ]?
                 [center <point>, ]?
                 radius [<length> | <percentage>],
                 [[repeat | reflect],]?
                 <color-stop>[, <color-stop>]+)
 

where

 <point> = [ [ <length> <length> ] | [ <percentage> | <percentage> ] ]
 <color-stop> = [ <color> [ <percentage> | <length>]? ]
 

Currently length can be only specified in px, the specification of unit can be omited. Format of color representation is the one used in Color.web(String color). The radial-gradient keyword can be omited. For additional information about the format of string representation, see the CSS Reference Guide.

Examples:

 RadialGradient g
      = RadialGradient.valueOf("radial-gradient(center 100px 100px, radius 200px, red  0%, blue 30%, black 100%)");
 RadialGradient g
      = RadialGradient.valueOf("center 100px 100px, radius 200px, red  0%, blue 30%, black 100%");
 RadialGradient g
      = RadialGradient.valueOf("radial-gradient(center 50% 50%, radius 50%,  cyan, violet 75%, magenta)");
 RadialGradient g
      = RadialGradient.valueOf("center 50% 50%, radius 50%,  cyan, violet 75%, magenta");
 

Parameters:

value - the string to convert

Returns:

a RadialGradient object holding the value represented by the string argument.

Throws:

NullPointerException - if the value is null

IllegalArgumentException - if the value cannot be parsed

Since:

JavaFX 2.1