/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.awt;
import java.awt.geom.AffineTransform;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.ColorModel;
import org.apache.harmony.awt.internal.nls.Messages;
/**
* The GradientPaint class defines a way to fill a Shape with a linear color
* gradient pattern.
* <p>
* The GradientPaint's fill pattern is determined by two points and two colors,
* plus the cyclic mode option. Each of the two points is painted with its
* corresponding color, and on the line segment connecting the two points, the
* color is proportionally changed between the two colors. For points on the
* same line which are not between the two specified points (outside of the
* connecting segment) their color is determined by the cyclic mode option. If
* the mode is cyclic, then the rest of the line repeats the color pattern of
* the connecting segment, cycling back and forth between the two colors. If
* not, the mode is acyclic which means that all points on the line outside the
* connecting line segment are given the same color as the closest of the two
* specified points.
* <p>
* The color of points that are not on the line connecting the two specified
* points are given by perpendicular projection: by taking the set of lines
* perpendicular to the connecting line and for each one, the whole line is
* colored with the same color.
*
* @since Android 1.0
*/
public class GradientPaint implements Paint {
/**
* The start point color.
*/
Color color1;
/**
* The end color point.
*/
Color color2;
/**
* The location of the start point.
*/
Point2D point1;
/**
* The location of the end point.
*/
Point2D point2;
/**
* The indicator of cycle filling. If TRUE filling repeated outside points
* stripe, if FALSE solid color filling outside.
*/
boolean cyclic;
/**
* Instantiates a new GradientPaint with cyclic or acyclic mode.
*
* @param point1
* the first specified point.
* @param color1
* the Color of the first specified point.
* @param point2
* the second specified point.
* @param color2
* the Color of the second specified point.
* @param cyclic
* the cyclic mode - true if the gradient pattern should cycle
* repeatedly between the two colors; false otherwise.
*/
public GradientPaint(Point2D point1, Color color1, Point2D point2, Color color2, boolean cyclic) {
if (point1 == null || point2 == null) {
// awt.6D=Point is null
throw new NullPointerException(Messages.getString("awt.6D")); //$NON-NLS-1$
}
if (color1 == null || color2 == null) {
// awt.6E=Color is null
throw new NullPointerException(Messages.getString("awt.6E")); //$NON-NLS-1$
}
this.point1 = point1;
this.point2 = point2;
this.color1 = color1;
this.color2 = color2;
this.cyclic = cyclic;
}
/**
* Instantiates a new GradientPaint with cyclic or acyclic mode; points are
* specified by coordinates.
*
* @param x1
* the X coordinate of the first point.
* @param y1
* the Y coordinate of the first point.
* @param color1
* the color of the first point.
* @param x2
* the X coordinate of the second point.
* @param y2
* the Y coordinate of the second point.
* @param color2
* the color of the second point.
* @param cyclic
* the cyclic mode - true if the gradient pattern should cycle
* repeatedly between the two colors; false otherwise.
*/
public GradientPaint(float x1, float y1, Color color1, float x2, float y2, Color color2,
boolean cyclic) {
this(new Point2D.Float(x1, y1), color1, new Point2D.Float(x2, y2), color2, cyclic);
}
/**
* Instantiates a new acyclic GradientPaint; points are specified by
* coordinates.
*
* @param x1
* the X coordinate of the first point.
* @param y1
* the Y coordinate of the first point.
* @param color1
* the color of the first point.
* @param x2
* the X coordinate of the second point.
* @param y2
* the Y coordinate of the second point.
* @param color2
* the color of the second point.
*/
public GradientPaint(float x1, float y1, Color color1, float x2, float y2, Color color2) {
this(x1, y1, color1, x2, y2, color2, false);
}
/**
* Instantiates a new acyclic GradientPaint.
*
* @param point1
* the first specified point.
* @param color1
* the Color of the first specified point.
* @param point2
* the second specified point.
* @param color2
* the Color of the second specified point.
*/
public GradientPaint(Point2D point1, Color color1, Point2D point2, Color color2) {
this(point1, color1, point2, color2, false);
}
/**
* Creates PaintContext for a color pattern generating.
*
* @param cm
* the ColorModel of the Paint data.
* @param deviceBounds
* the bounding Rectangle of graphics primitives being rendered
* in the device space.
* @param userBounds
* the bounding Rectangle of graphics primitives being rendered
* in the user space.
* @param t
* the AffineTransform from user space into device space.
* @param hints
* the RrenderingHints object.
* @return the PaintContext for color pattern generating.
* @see java.awt.Paint#createContext(java.awt.image.ColorModel,
* java.awt.Rectangle, java.awt.geom.Rectangle2D,
* java.awt.geom.AffineTransform, java.awt.RenderingHints)
*/
public PaintContext createContext(ColorModel cm, Rectangle deviceBounds,
Rectangle2D userBounds, AffineTransform t, RenderingHints hints) {
return new GradientPaintContext(cm, t, point1, color1, point2, color2, cyclic);
}
/**
* Gets the color of the first point.
*
* @return the color of the first point.
*/
public Color getColor1() {
return color1;
}
/**
* Gets the color of the second point.
*
* @return the color of the second point.
*/
public Color getColor2() {
return color2;
}
/**
* Gets the first point.
*
* @return the Point object - the first point.
*/
public Point2D getPoint1() {
return point1;
}
/**
* Gets the second point.
*
* @return the Point object - the second point.
*/
public Point2D getPoint2() {
return point2;
}
/**
* Gets the transparency mode for the GradientPaint.
*
* @return the transparency mode for the GradientPaint.
* @see java.awt.Transparency#getTransparency()
*/
public int getTransparency() {
int a1 = color1.getAlpha();
int a2 = color2.getAlpha();
return (a1 == 0xFF && a2 == 0xFF) ? OPAQUE : TRANSLUCENT;
}
/**
* Returns the GradientPaint mode: true for cyclic mode, false for acyclic
* mode.
*
* @return true if the gradient cycles repeatedly between the two colors;
* false otherwise.
*/
public boolean isCyclic() {
return cyclic;
}
}