/*

 * Copyright (c) 2005, 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.

 */

/*

 * (C) Copyright IBM Corp. 2005, All Rights Reserved.

 */

package java.awt.font;

import java.awt.geom.Point2D;

/**

 * LayoutPath provides a mapping between locations relative to the

 * baseline and points in user space.  Locations consist of an advance

 * along the baseline, and an offset perpendicular to the baseline at

 * the advance.  Positive values along the perpendicular are in the

 * direction that is 90 degrees clockwise from the baseline vector.

 * Locations are represented as a <code>Point2D</code>, where x is the advance and

 * y is the offset.

 *

 * @since 1.6

 */

public abstract class LayoutPath {

    /**

     * Convert a point in user space to a location relative to the

     * path. The location is chosen so as to minimize the distance

     * from the point to the path (e.g., the magnitude of the offset

     * will be smallest).  If there is more than one such location,

     * the location with the smallest advance is chosen.

     * @param point the point to convert.  If it is not the same

     * object as location, point will remain unmodified by this call.

     * @param location a <code>Point2D</code> to hold the returned location.

     * It can be the same object as point.

     * @return true if the point is associated with the portion of the

     * path preceding the location, false if it is associated with

     * the portion following.  The default, if the location is not at

     * a break or sharp bend in the path, is to return true.

     * @throws NullPointerException if point or location is null

     * @since 1.6

     */

    public abstract boolean pointToPath(Point2D point, Point2D location);

    /**

     * Convert a location relative to the path to a point in user

     * coordinates.  The path might bend abruptly or be disjoint at

     * the location's advance.  If this is the case, the value of

     * 'preceding' is used to disambiguate the portion of the path

     * whose location and slope is to be used to interpret the offset.

     * @param location a <code>Point2D</code> representing the advance (in x) and

     * offset (in y) of a location relative to the path.  If location

     * is not the same object as point, location will remain

     * unmodified by this call.

     * @param preceding if true, the portion preceding the advance

     * should be used, if false the portion after should be used.

     * This has no effect if the path does not break or bend sharply

     * at the advance.

     * @param point a <code>Point2D</code> to hold the returned point.  It can be

     * the same object as location.

     * @throws NullPointerException if location or point is null

     * @since 1.6

     */

    public abstract void pathToPoint(Point2D location, boolean preceding,

                                     Point2D point);

}