    001/* ===========================================================
    002 * Orson Charts : a 3D chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C)opyright 2013-2016, by Object Refinery Limited.  All rights reserved.
    006 *
    007 * http://www.object-refinery.com/orsoncharts/index.html
    008 *
    009 * This program is free software: you can redistribute it and/or modify
    010 * it under the terms of the GNU General Public License as published by
    011 * the Free Software Foundation, either version 3 of the License, or
    012 * (at your option) any later version.
    013 *
    014 * This program is distributed in the hope that it will be useful,
    015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
    016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    017 * GNU General Public License for more details.
    018 *
    019 * You should have received a copy of the GNU General Public License
    020 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    021 *
    022 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    023 * Other names may be trademarks of their respective owners.]
    024 *
    025 * If you do not wish to be bound by the terms of the GPL, an alternative
    026 * commercial license can be purchased.  For details, please see visit the
    027 * Orson Charts home page:
    028 *
    029 * http://www.object-refinery.com/orsoncharts/index.html
    030 *
    031 */
    032
    033package com.orsoncharts.util;
    034
    035import java.awt.geom.Point2D;
    036import java.awt.geom.Rectangle2D;
    037import java.io.Serializable;
    038
    039import com.orsoncharts.TitleAnchor;
    040import com.orsoncharts.graphics3d.Offset2D;
    041import com.orsoncharts.legend.LegendAnchor;
    042
    043/**
    044 * Represents an anchor point for a chart title and/or legend.  The anchor
    045 * point is defined relative to a reference rectangle, the dimensions of which
    046 * are not known in advance (typically the reference rectangle is the bounding
    047 * rectangle of a chart that is being drawn).  Some predefined anchor points
    048 * are provided in the {@link TitleAnchor} and {@link LegendAnchor} classes.
    049 * <br><br>
    050 * Instances of this class are immutable.
    051 * <br><br>
    052 * NOTE: This class is serializable, but the serialization format is subject
    053 * to change in future releases and should not be relied upon for persisting
    054 * instances of this class.
    055 */
    056@SuppressWarnings("serial")
    057public final class Anchor2D implements Serializable {
    058
    059    /**
    060     * An anchor point at the top left with zero offset from the target
    061     * rectangle bounds.
    062     *
    063     * @since 1.1
    064     */
    065    public static final Anchor2D TOP_LEFT = new Anchor2D(RefPt2D.TOP_LEFT,
    066            Offset2D.ZERO_OFFSET);
    067
    068    /**
    069     * An anchor point at the top center with zero offset from the target
    070     * rectangle bounds.
    071     *
    072     * @since 1.1
    073     */
    074    public static final Anchor2D TOP_CENTER = new Anchor2D(RefPt2D.TOP_CENTER,
    075            Offset2D.ZERO_OFFSET);
    076
    077    /**
    078     * An anchor point at the top right with zero offset from the target
    079     * rectangle bounds.
    080     *
    081     * @since 1.1
    082     */
    083    public static final Anchor2D TOP_RIGHT = new Anchor2D(RefPt2D.TOP_RIGHT,
    084            Offset2D.ZERO_OFFSET);
    085
    086    /**
    087     * An anchor point at the center left with zero offset from the target
    088     * rectangle bounds.
    089     *
    090     * @since 1.1
    091     */
    092    public static final Anchor2D CENTER_LEFT = new Anchor2D(RefPt2D.CENTER_LEFT,
    093            Offset2D.ZERO_OFFSET);
    094
    095    /**
    096     * An anchor point at the center of the target rectangle.
    097     *
    098     * @since 1.1
    099     */
    100    public static final Anchor2D CENTER = new Anchor2D(RefPt2D.CENTER,
    101            Offset2D.ZERO_OFFSET);
    102
    103    /**
    104     * An anchor point at the center right with zero offset from the target
    105     * rectangle bounds.
    106     *
    107     * @since 1.1
    108     */
    109    public static final Anchor2D CENTER_RIGHT
    110            = new Anchor2D(RefPt2D.CENTER_RIGHT, Offset2D.ZERO_OFFSET);
    111
    112    /**
    113     * An anchor point at the bottom left with zero offset from the target
    114     * rectangle bounds.
    115     *
    116     * @since 1.1
    117     */
    118    public static final Anchor2D BOTTOM_LEFT = new Anchor2D(RefPt2D.BOTTOM_LEFT,
    119            Offset2D.ZERO_OFFSET);
    120
    121    /**
    122     * An anchor point at the bottom center with zero offset from the target
    123     * rectangle bounds.
    124     *
    125     * @since 1.1
    126     */
    127    public static final Anchor2D BOTTOM_CENTER
    128            = new Anchor2D(RefPt2D.BOTTOM_CENTER, Offset2D.ZERO_OFFSET);
    129
    130    /**
    131     * An anchor point at the bottom right with zero offset from the target
    132     * rectangle bounds.
    133     *
    134     * @since 1.1
    135     */
    136    public static final Anchor2D BOTTOM_RIGHT
    137            = new Anchor2D(RefPt2D.BOTTOM_RIGHT, Offset2D.ZERO_OFFSET);
    138
    139    /**
    140     * The reference point relative to some bounding rectangle, normally the
    141     * bounds of the chart (never {@code null}).
    142     */
    143    private RefPt2D refPt;
    144
    145    /**
    146     * The offsets to apply (never {@code null}).
    147     */
    148    private Offset2D offset;
    149
    150    /**
    151     * Creates a default instance.
    152     */
    153    public Anchor2D() {
    154        this(RefPt2D.TOP_LEFT);
    155    }
    156
    157    /**
    158     * Creates a new {@code Anchor2D} instance with the specified
    159     * reference point and offsets of {@code (4.0, 4.0)}.
    160     *
    161     * @param refPt  the reference point ({@code null} not permitted).
    162     */
    163    public Anchor2D(RefPt2D refPt) {
    164        this(refPt, new Offset2D(4.0, 4.0));
    165    }
    166
    167    /**
    168     * Creates a new anchor.
    169     *
    170     * @param refPt  the reference point ({@code null} not permitted).
    171     * @param offset  the offset ({@code null} not permitted).
    172     */
    173    public Anchor2D(RefPt2D refPt, Offset2D offset) {
    174        ArgChecks.nullNotPermitted(refPt, "refPt");
    175        ArgChecks.nullNotPermitted(offset, "offset");
    176        this.refPt = refPt;
    177        this.offset = offset;
    178    }
    179
    180    /**
    181     * Returns the reference point.
    182     *
    183     * @return The reference point (never {@code null}).
    184     */
    185    public RefPt2D getRefPt() {
    186        return this.refPt;
    187    }
    188
    189    /**
    190     * Returns the offsets.
    191     *
    192     * @return The offsets (never {@code null}).
    193     */
    194    public Offset2D getOffset() {
    195        return this.offset;
    196    }
    197
    198    /**
    199     * Returns the anchor point for the given rectangle.
    200     *
    201     * @param rect  the reference rectangle ({@code null} not permitted).
    202     *
    203     * @return The anchor point.
    204     */
    205    public Point2D getAnchorPoint(Rectangle2D rect) {
    206        ArgChecks.nullNotPermitted(rect, "rect");
    207        double x = 0.0;
    208        double y = 0.0;
    209        if (this.refPt.isLeft()) {
    210            x = rect.getX() + this.offset.getDX();
    211        } else if (this.refPt.isHorizontalCenter()) {
    212            x = rect.getCenterX();
    213        } else if (this.refPt.isRight()) {
    214            x = rect.getMaxX() - this.offset.getDX();
    215        }
    216        if (this.refPt.isTop()) {
    217            y = rect.getMinY() + this.offset.getDY();
    218        } else if (this.refPt.isVerticalCenter()) {
    219            y = rect.getCenterY();
    220        } else if (this.refPt.isBottom()) {
    221            y = rect.getMaxY() - this.offset.getDY();
    222        }
    223        return new Point2D.Double(x, y);
    224    }
    225
    226    /**
    227     * Resolves the anchor to a specific point relative to a rectangle defined
    228     * by the points (startX, startY) and (endX, endY).
    229     *
    230     * @param startX  the x-coordinate for the bottom left corner of the target
    231     *     rect.
    232     * @param startY  the y-coordinate for the bottom left corner of the target
    233     *     rect.
    234     * @param endX  the x-coordinate for the top right corner of the target
    235     *     rect.
    236     * @param endY  the y-coordinate for the top right corner of the target
    237     *     rect.
    238     *
    239     * @return The resolved point.
    240     *
    241     * @since 1.2
    242     */
    243    public Point2D resolveAnchorWithPercentOffset(double startX, double startY,
    244            double endX, double endY) {
    245        double x = 0.0;
    246        double y = 0.0;
    247        if (this.refPt.isLeft()) {
    248            x = startX + this.offset.getDX() * (endX - startX);
    249        } else if (this.refPt.isHorizontalCenter()) {
    250            x = (startX + endX) / 2.0;
    251        } else if (this.refPt.isRight()) {
    252            x = endX - this.offset.getDX() * (endX - startX);
    253        }
    254        if (this.refPt.isTop()) {
    255            y = endY - this.offset.getDY() * (endY - startY);
    256        } else if (this.refPt.isVerticalCenter()) {
    257            y = (startY + endY) / 2.0;
    258        } else if (this.refPt.isBottom()) {
    259            y = startY + this.offset.getDY() * (endY - startY);
    260        }
    261        return new Point2D.Double(x, y);
    262    }
    263
    264    /**
    265     * Tests this instance for equality with an arbitrary object.
    266     *
    267     * @param obj  the object ({@code null} not permitted).
    268     *
    269     * @return A boolean.
    270     */
    271    @Override
    272    public boolean equals(Object obj) {
    273        if (obj == this) {
    274            return true;
    275        }
    276        if (!(obj instanceof Anchor2D)) {
    277            return false;
    278        }
    279        Anchor2D that = (Anchor2D) obj;
    280        if (!this.refPt.equals(that.refPt)) {
    281            return false;
    282        }
    283        if (!this.offset.equals(that.offset)) {
    284            return false;
    285        }
    286        return true;
    287    }
    288}