org.apache.batik.ext.awt
public final class LinearGradientPaint extends MultipleGradientPaint
LinearGradientPaint
class provides a way to fill
a {@link java.awt.Shape} with a linear color gradient pattern. The user may
specify 2 or more gradient colors, and this paint will provide an
interpolation between each color. The user also specifies start and end
points which define where in user space the color gradient should begin
and end.
The user must provide an array of floats specifying how to distribute the colors along the gradient. These values should range from 0.0 to 1.0 and act like keyframes along the gradient (they mark where the gradient should be exactly a particular color).
For example:
Point2D start = new Point2D.Float(0, 0);
Point2D end = new Point2D.Float(100,100);
float[] dist = {0.0, 0.2, 1.0};
Color[] colors = {Color.red, Color.white, Color.blue};
LinearGradientPaint p = new LinearGradientPaint(start, end, dist, colors);
This code will create a LinearGradientPaint which interpolates between red and white for the first 20% of the gradient and between white and blue for the remaining 80%.
In the event that the user does not set the first keyframe value equal
to 0 and the last keyframe value equal to 1, keyframes will be created at
these positions and the first and last colors will be replicated there.
So, if a user specifies the following arrays to construct a gradient:
{Color.blue, Color.red}, {.3, .7}
this will be converted to a gradient with the following keyframes:
{Color.blue, Color.blue, Color.red, Color.red}, {0, .3, .7, 1}
The user may also select what action the LinearGradientPaint should take when filling color outside the start and end points. If no cycle method is specified, NO_CYCLE will be chosen by default, so the endpoint colors will be used to fill the remaining area.
The following image demonstrates the options NO_CYCLE and REFLECT.
The colorSpace parameter allows the user to specify in which colorspace the interpolation should be performed, default sRGB or linearized RGB.
See Also: java.awt.Paint java.awt.Graphics2D#setPaint
Constructor Summary | |
---|---|
LinearGradientPaint(float startX, float startY, float endX, float endY, float[] fractions, Color[] colors)
Constructs an | |
LinearGradientPaint(float startX, float startY, float endX, float endY, float[] fractions, Color[] colors, CycleMethodEnum cycleMethod)
Constructs an | |
LinearGradientPaint(Point2D start, Point2D end, float[] fractions, Color[] colors)
Constructs a | |
LinearGradientPaint(Point2D start, Point2D end, float[] fractions, Color[] colors, CycleMethodEnum cycleMethod, ColorSpaceEnum colorSpace)
Constructs a | |
LinearGradientPaint(Point2D start, Point2D end, float[] fractions, Color[] colors, CycleMethodEnum cycleMethod, ColorSpaceEnum colorSpace, AffineTransform gradientTransform)
Constructs a |
Method Summary | |
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PaintContext | createContext(ColorModel cm, Rectangle deviceBounds, Rectangle2D userBounds, AffineTransform transform, RenderingHints hints)
Creates and returns a PaintContext used to generate the color pattern,
for use by the internal rendering engine.
|
Point2D | getEndPoint() Returns a copy of the end point of the gradient axis |
Point2D | getStartPoint()
Returns a copy of the start point of the gradient axis |
Constructs an LinearGradientPaint
with the default
NO_CYCLE repeating method and SRGB colorspace.
Parameters: startX the x coordinate of the gradient axis start point in user space startY the y coordinate of the gradient axis start point in user space endX the x coordinate of the gradient axis end point in user space endY the y coordinate of the gradient axis end point in user space fractions numbers ranging from 0.0 to 1.0 specifying the distribution of colors along the gradient colors array of colors corresponding to each fractional value
Throws: IllegalArgumentException if start and end points are the same points, or if fractions.length != colors.length, or if colors is less than 2 in size.
Constructs an LinearGradientPaint
with default SRGB
colorspace.
Parameters: startX the x coordinate of the gradient axis start point in user space startY the y coordinate of the gradient axis start point in user space endX the x coordinate of the gradient axis end point in user space endY the y coordinate of the gradient axis end point in user space fractions numbers ranging from 0.0 to 1.0 specifying the distribution of colors along the gradient colors array of colors corresponding to each fractional value cycleMethod either NO_CYCLE, REFLECT, or REPEAT
Throws: IllegalArgumentException if start and end points are the same points, or if fractions.length != colors.length, or if colors is less than 2 in size.
Constructs a LinearGradientPaint
with the default
NO_CYCLE repeating method and SRGB colorspace.
Parameters: start the gradient axis start Point
in user space
end the gradient axis end Point
in user space
fractions numbers ranging from 0.0 to 1.0 specifying the
distribution of colors along the gradient
colors array of colors corresponding to each fractional value
Throws: NullPointerException if one of the points is null IllegalArgumentException if start and end points are the same points, or if fractions.length != colors.length, or if colors is less than 2 in size.
Constructs a LinearGradientPaint
.
Parameters: start the gradient axis start Point
in user space
end the gradient axis end Point
in user space
fractions numbers ranging from 0.0 to 1.0 specifying the
distribution of colors along the gradient
colors array of colors corresponding to each fractional value
cycleMethod either NO_CYCLE, REFLECT, or REPEAT
colorSpace which colorspace to use for interpolation,
either SRGB or LINEAR_RGB
Throws: NullPointerException if one of the points is null IllegalArgumentException if start and end points are the same points, or if fractions.length != colors.length, or if colors is less than 2 in size.
Constructs a LinearGradientPaint
.
Parameters: start the gradient axis start Point
in user space
end the gradient axis end Point
in user space
fractions numbers ranging from 0.0 to 1.0 specifying the
distribution of colors along the gradient
colors array of colors corresponding to each fractional value
cycleMethod either NO_CYCLE, REFLECT, or REPEAT
colorSpace which colorspace to use for interpolation,
either SRGB or LINEAR_RGB
gradientTransform transform to apply to the gradient
Throws: NullPointerException if one of the points is null, or gradientTransform is null IllegalArgumentException if start and end points are the same points, or if fractions.length != colors.length, or if colors is less than 2 in size.
Parameters: cm {@link ColorModel} that receives
the Paint
data. This is used only as a hint.
deviceBounds the device space bounding box of the
graphics primitive being rendered
userBounds the user space bounding box of the
graphics primitive being rendered
transform the {@link AffineTransform} from user
space into device space
hints the hints that the context object uses to choose
between rendering alternatives
Returns: the {@link PaintContext} that generates color patterns.
See Also: PaintContext
Returns: a {@link Point2D} object that is a copy of the point
that anchors the last color of this
LinearGradientPaint
.
Returns: a {@link Point2D} object that is a copy of the point
that anchors the first color of this
LinearGradientPaint
.