| /* |
| * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.awt; |
| |
| import java.awt.geom.Point2D; |
| import java.awt.geom.Rectangle2D; |
| import java.awt.geom.AffineTransform; |
| import java.awt.image.ColorModel; |
| import java.beans.ConstructorProperties; |
| |
| /** |
| * The <code>GradientPaint</code> class provides a way to fill |
| * a {@link Shape} with a linear color gradient pattern. |
| * If {@link Point} P1 with {@link Color} C1 and <code>Point</code> P2 with |
| * <code>Color</code> C2 are specified in user space, the |
| * <code>Color</code> on the P1, P2 connecting line is proportionally |
| * changed from C1 to C2. Any point P not on the extended P1, P2 |
| * connecting line has the color of the point P' that is the perpendicular |
| * projection of P on the extended P1, P2 connecting line. |
| * Points on the extended line outside of the P1, P2 segment can be colored |
| * in one of two ways. |
| * <ul> |
| * <li> |
| * If the gradient is cyclic then the points on the extended P1, P2 |
| * connecting line cycle back and forth between the colors C1 and C2. |
| * <li> |
| * If the gradient is acyclic then points on the P1 side of the segment |
| * have the constant <code>Color</code> C1 while points on the P2 side |
| * have the constant <code>Color</code> C2. |
| * </ul> |
| * |
| * @see Paint |
| * @see Graphics2D#setPaint |
| * @version 10 Feb 1997 |
| */ |
| |
| public class GradientPaint implements Paint { |
| Point2D.Float p1; |
| Point2D.Float p2; |
| Color color1; |
| Color color2; |
| boolean cyclic; |
| |
| /** |
| * Constructs a simple acyclic <code>GradientPaint</code> object. |
| * @param x1 x coordinate of the first specified |
| * <code>Point</code> in user space |
| * @param y1 y coordinate of the first specified |
| * <code>Point</code> in user space |
| * @param color1 <code>Color</code> at the first specified |
| * <code>Point</code> |
| * @param x2 x coordinate of the second specified |
| * <code>Point</code> in user space |
| * @param y2 y coordinate of the second specified |
| * <code>Point</code> in user space |
| * @param color2 <code>Color</code> at the second specified |
| * <code>Point</code> |
| * @throws NullPointerException if either one of colors is null |
| */ |
| public GradientPaint(float x1, |
| float y1, |
| Color color1, |
| float x2, |
| float y2, |
| Color color2) { |
| if ((color1 == null) || (color2 == null)) { |
| throw new NullPointerException("Colors cannot be null"); |
| } |
| |
| p1 = new Point2D.Float(x1, y1); |
| p2 = new Point2D.Float(x2, y2); |
| this.color1 = color1; |
| this.color2 = color2; |
| } |
| |
| /** |
| * Constructs a simple acyclic <code>GradientPaint</code> object. |
| * @param pt1 the first specified <code>Point</code> in user space |
| * @param color1 <code>Color</code> at the first specified |
| * <code>Point</code> |
| * @param pt2 the second specified <code>Point</code> in user space |
| * @param color2 <code>Color</code> at the second specified |
| * <code>Point</code> |
| * @throws NullPointerException if either one of colors or points |
| * is null |
| */ |
| public GradientPaint(Point2D pt1, |
| Color color1, |
| Point2D pt2, |
| Color color2) { |
| if ((color1 == null) || (color2 == null) || |
| (pt1 == null) || (pt2 == null)) { |
| throw new NullPointerException("Colors and points should be non-null"); |
| } |
| |
| p1 = new Point2D.Float((float)pt1.getX(), (float)pt1.getY()); |
| p2 = new Point2D.Float((float)pt2.getX(), (float)pt2.getY()); |
| this.color1 = color1; |
| this.color2 = color2; |
| } |
| |
| /** |
| * Constructs either a cyclic or acyclic <code>GradientPaint</code> |
| * object depending on the <code>boolean</code> parameter. |
| * @param x1 x coordinate of the first specified |
| * <code>Point</code> in user space |
| * @param y1 y coordinate of the first specified |
| * <code>Point</code> in user space |
| * @param color1 <code>Color</code> at the first specified |
| * <code>Point</code> |
| * @param x2 x coordinate of the second specified |
| * <code>Point</code> in user space |
| * @param y2 y coordinate of the second specified |
| * <code>Point</code> in user space |
| * @param color2 <code>Color</code> at the second specified |
| * <code>Point</code> |
| * @param cyclic <code>true</code> if the gradient pattern should cycle |
| * repeatedly between the two colors; <code>false</code> otherwise |
| */ |
| public GradientPaint(float x1, |
| float y1, |
| Color color1, |
| float x2, |
| float y2, |
| Color color2, |
| boolean cyclic) { |
| this (x1, y1, color1, x2, y2, color2); |
| this.cyclic = cyclic; |
| } |
| |
| /** |
| * Constructs either a cyclic or acyclic <code>GradientPaint</code> |
| * object depending on the <code>boolean</code> parameter. |
| * @param pt1 the first specified <code>Point</code> |
| * in user space |
| * @param color1 <code>Color</code> at the first specified |
| * <code>Point</code> |
| * @param pt2 the second specified <code>Point</code> |
| * in user space |
| * @param color2 <code>Color</code> at the second specified |
| * <code>Point</code> |
| * @param cyclic <code>true</code> if the gradient pattern should cycle |
| * repeatedly between the two colors; <code>false</code> otherwise |
| * @throws NullPointerException if either one of colors or points |
| * is null |
| */ |
| @ConstructorProperties({ "point1", "color1", "point2", "color2", "cyclic" }) |
| public GradientPaint(Point2D pt1, |
| Color color1, |
| Point2D pt2, |
| Color color2, |
| boolean cyclic) { |
| this (pt1, color1, pt2, color2); |
| this.cyclic = cyclic; |
| } |
| |
| /** |
| * Returns a copy of the point P1 that anchors the first color. |
| * @return a {@link Point2D} object that is a copy of the point |
| * that anchors the first color of this |
| * <code>GradientPaint</code>. |
| */ |
| public Point2D getPoint1() { |
| return new Point2D.Float(p1.x, p1.y); |
| } |
| |
| /** |
| * Returns the color C1 anchored by the point P1. |
| * @return a <code>Color</code> object that is the color |
| * anchored by P1. |
| */ |
| public Color getColor1() { |
| return color1; |
| } |
| |
| /** |
| * Returns a copy of the point P2 which anchors the second color. |
| * @return a {@link Point2D} object that is a copy of the point |
| * that anchors the second color of this |
| * <code>GradientPaint</code>. |
| */ |
| public Point2D getPoint2() { |
| return new Point2D.Float(p2.x, p2.y); |
| } |
| |
| /** |
| * Returns the color C2 anchored by the point P2. |
| * @return a <code>Color</code> object that is the color |
| * anchored by P2. |
| */ |
| public Color getColor2() { |
| return color2; |
| } |
| |
| /** |
| * Returns <code>true</code> if the gradient cycles repeatedly |
| * between the two colors C1 and C2. |
| * @return <code>true</code> if the gradient cycles repeatedly |
| * between the two colors; <code>false</code> otherwise. |
| */ |
| public boolean isCyclic() { |
| return cyclic; |
| } |
| |
| /** |
| * Creates and returns a {@link PaintContext} used to |
| * generate a linear color gradient pattern. |
| * See the {@link Paint#createContext specification} of the |
| * method in the {@link Paint} interface for information |
| * on null parameter handling. |
| * |
| * @param cm the preferred {@link ColorModel} which represents the most convenient |
| * format for the caller to receive the pixel data, or {@code null} |
| * if there is no preference. |
| * @param deviceBounds the device space bounding box |
| * of the graphics primitive being rendered. |
| * @param userBounds the user space bounding box |
| * of the graphics primitive being rendered. |
| * @param xform the {@link AffineTransform} from user |
| * space into device space. |
| * @param hints the set of hints that the context object can use to |
| * choose between rendering alternatives. |
| * @return the {@code PaintContext} for |
| * generating color patterns. |
| * @see Paint |
| * @see PaintContext |
| * @see ColorModel |
| * @see Rectangle |
| * @see Rectangle2D |
| * @see AffineTransform |
| * @see RenderingHints |
| */ |
| public PaintContext createContext(ColorModel cm, |
| Rectangle deviceBounds, |
| Rectangle2D userBounds, |
| AffineTransform xform, |
| RenderingHints hints) { |
| |
| return new GradientPaintContext(cm, p1, p2, xform, |
| color1, color2, cyclic); |
| } |
| |
| /** |
| * Returns the transparency mode for this <code>GradientPaint</code>. |
| * @return an integer value representing this <code>GradientPaint</code> |
| * object's transparency mode. |
| * @see Transparency |
| */ |
| public int getTransparency() { |
| int a1 = color1.getAlpha(); |
| int a2 = color2.getAlpha(); |
| return (((a1 & a2) == 0xff) ? OPAQUE : TRANSLUCENT); |
| } |
| |
| } |
