The
LinearGradientPaint
class provides a way to fill
a
Shape
with a linear color gradient pattern. The user
may specify two 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).
In the event that the user does not set the first keyframe value equal
to 0 and/or 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}, {.3f, .7f}
this will be converted to a gradient with the following keyframes:
{Color.BLUE, Color.BLUE, Color.RED, Color.RED}, {0f, .3f, .7f, 1f}
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, which means the endpoint colors will be used to fill the
remaining area.
The colorSpace parameter allows the user to specify in which colorspace
the interpolation should be performed, default sRGB or linearized RGB.
The following code demonstrates typical usage of
LinearGradientPaint
:
Point2D start = new Point2D.Float(0, 0);
Point2D end = new Point2D.Float(50, 50);
float[] dist = {0.0f, 0.2f, 1.0f};
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%.
This image demonstrates the example code above for each
of the three cycle methods: