OverUnderDelimiter.java

/* OverUnderDelimiter.java
 * =========================================================================
 * This file is originally part of the JMathTeX Library - http://jmathtex.sourceforge.net
 *
 * Copyright (C) 2004-2007 Universiteit Gent
 * Copyright (C) 2009-2010 DENIZET Calixte
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program 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 for more details.
 *
 * A copy of the GNU General Public License can be found in the file
 * LICENSE.txt provided with the source distribution of this program (see
 * the META-INF directory in the source jar). This license can also be
 * found on the GNU website at http://www.gnu.org/licenses/gpl.html.
 *
 * If you did not receive a copy of the GNU General Public License along
 * with this program, contact the lead developer, or write to the Free
 * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 * Linking this library statically or dynamically with other modules
 * is making a combined work based on this library. Thus, the terms
 * and conditions of the GNU General Public License cover the whole
 * combination.
 *
 * As a special exception, the copyright holders of this library give you
 * permission to link this library with independent modules to produce
 * an executable, regardless of the license terms of these independent
 * modules, and to copy and distribute the resulting executable under terms
 * of your choice, provided that you also meet, for each linked independent
 * module, the terms and conditions of the license of that module.
 * An independent module is a module which is not derived from or based
 * on this library. If you modify this library, you may extend this exception
 * to your version of the library, but you are not obliged to do so.
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 *
 */

package org.scilab.forge.jlatexmath;

/**
 * A box representing another atom with a delimiter and a script above or under it,
 * with script and delimiter separated by a kern.
 */
public class OverUnderDelimiter extends Atom {

    // base and script atom
    private final Atom base;
    private Atom script;

    // delimiter symbol
    private final SymbolAtom symbol;

    // kern between delimiter and script
    private final SpaceAtom kern;

    // whether the delimiter should be positioned above or under the base
    private final boolean over;

    public OverUnderDelimiter(Atom base, Atom script, SymbolAtom s, int kernUnit,
                              float kern, boolean over) throws InvalidUnitException {
        type = TeXConstants.TYPE_INNER;
        this.base = base;
        this.script = script;
        symbol = s;
        this.kern = new SpaceAtom(kernUnit, 0, kern, 0);
        this.over = over;
    }

    public void addScript(Atom script) {
        this.script = script;
    }

    public boolean isOver() {
        return over;
    }

    public Box createBox(TeXEnvironment env) {
        Box b = (base == null ? new StrutBox(0, 0, 0, 0) : base.createBox(env));
        Box del = DelimiterFactory.create(symbol.getName(), env, b.getWidth());

        Box scriptBox = null;
        if (script != null) {
            scriptBox = script.createBox((over ? env.supStyle() : env.subStyle()));
        }

        // create centered horizontal box if smaller than maximum width
        float max = getMaxWidth(b, del, scriptBox);
        if (max - b.getWidth() > TeXFormula.PREC) {
            b = new HorizontalBox(b, max, TeXConstants.ALIGN_CENTER);
        }

        del = new VerticalBox(del, max, TeXConstants.ALIGN_CENTER);
        if (scriptBox != null && max - scriptBox.getWidth() > TeXFormula.PREC) {
            scriptBox = new HorizontalBox(scriptBox, max, TeXConstants.ALIGN_CENTER);
        }

        return new OverUnderBox(b, del, scriptBox, kern.createBox(env).getHeight(), over);
    }

    private static float getMaxWidth(Box b, Box del, Box script) {
        float max = Math.max(b.getWidth(), del.getHeight() + del.getDepth());
        if (script != null) {
            max = Math.max(max, script.getWidth());
        }

        return max;
    }
}