BigOperatorAtom.java
/* BigOperatorAtom.java
* =========================================================================
* This file is originally part of the JMathTeX Library - http://jmathtex.sourceforge.net
*
* Copyright (C) 2004-2007 Universiteit Gent
* Copyright (C) 2009 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
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* of your choice, provided that you also meet, for each linked independent
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*/
/* Modified by Calixte Denizet */
package org.scilab.forge.jlatexmath;
/**
* An atom representing a "big operator" (or an atom that acts as one) together
* with its limits.
*/
public class BigOperatorAtom extends Atom {
// limits
private Atom under = null, over = null;
// atom representing a big operator
protected Atom base = null;
// whether the "limits"-value should be taken into account
// (otherwise the default rules will be applied)
private boolean limitsSet = false;
// whether limits should be drawn over and under the base (<-> as scripts)
private boolean limits = false;
/**
* Creates a new BigOperatorAtom from the given atoms.
* The default rules the positioning of the limits will be applied.
*
* @param base atom representing the big operator
* @param under atom representing the under limit
* @param over atom representing the over limit
*/
public BigOperatorAtom(Atom base, Atom under, Atom over) {
this.base = base;
this.under = under;
this.over = over;
type = TeXConstants.TYPE_BIG_OPERATOR;
}
/**
* Creates a new BigOperatorAtom from the given atoms.
* Limits will be drawn according to the "limits"-value
*
* @param base atom representing the big operator
* @param under atom representing the under limit
* @param over atom representing the over limit
* @param limits whether limits should be drawn over and under the base (rather than as scripts)
*/
public BigOperatorAtom(Atom base, Atom under, Atom over, boolean limits) {
this(base, under, over);
this.limits = limits;
limitsSet = true;
}
public Box createBox(TeXEnvironment env) {
TeXFont tf = env.getTeXFont();
int style = env.getStyle();
Box y;
float delta;
RowAtom bbase = null;
Atom Base = base;
if (base instanceof TypedAtom) {
Atom at = ((TypedAtom)base).getBase();
if (at instanceof RowAtom && ((RowAtom)at).lookAtLastAtom && base.type_limits != TeXConstants.SCRIPT_LIMITS) {
base = ((RowAtom)at).getLastAtom();
bbase = (RowAtom)at;
} else
base = at;
}
if ((limitsSet && !limits)
|| (!limitsSet && style >= TeXConstants.STYLE_TEXT)
|| (base.type_limits == TeXConstants.SCRIPT_NOLIMITS)
|| (base.type_limits == TeXConstants.SCRIPT_NORMAL && style >= TeXConstants.STYLE_TEXT)) {
// if explicitly set to not display as limits or if not set and style
// is not display, then attach over and under as regular sub- en
// superscript
if (bbase != null) {
bbase.add(new ScriptsAtom(base, under, over));
Box b = bbase.createBox(env);
bbase.getLastAtom();
bbase.add(base);
base = Base;
return b;
}
return new ScriptsAtom(base, under, over).createBox(env);
} else {
if (base instanceof SymbolAtom
&& base.type == TeXConstants.TYPE_BIG_OPERATOR) { // single
// bigop
// symbol
Char c = tf.getChar(((SymbolAtom) base).getName(), style);
y = base.createBox(env);
// include delta in width
delta = c.getItalic();
} else { // formula
delta = 0;
y = new HorizontalBox(base == null ? new StrutBox(0, 0, 0, 0)
: base.createBox(env));
}
// limits
Box x = null, z = null;
if (over != null)
x = over.createBox(env.supStyle());
if (under != null)
z = under.createBox(env.subStyle());
// make boxes equally wide
float maxWidth = Math.max(Math.max(x == null ? 0 : x.getWidth(), y
.getWidth()), z == null ? 0 : z.getWidth());
x = changeWidth(x, maxWidth);
y = changeWidth(y, maxWidth);
z = changeWidth(z, maxWidth);
// build vertical box
VerticalBox vBox = new VerticalBox();
float bigop5 = tf.getBigOpSpacing5(style), kern = 0;
float xh = 0; // TODO: check why this is not used // NOPMD
// over
if (over != null) {
vBox.add(new StrutBox(0, bigop5, 0, 0));
x.setShift(delta / 2);
vBox.add(x);
kern = Math.max(tf.getBigOpSpacing1(style), tf
.getBigOpSpacing3(style)
- x.getDepth());
vBox.add(new StrutBox(0, kern, 0, 0));
xh = vBox.getHeight() + vBox.getDepth();
}
// base
vBox.add(y);
// under
if (under != null) {
float k = Math.max(tf.getBigOpSpacing2(style), tf
.getBigOpSpacing4(style)
- z.getHeight());
vBox.add(new StrutBox(0, k, 0, 0));
z.setShift(-delta / 2);
vBox.add(z);
vBox.add(new StrutBox(0, bigop5, 0, 0));
}
// set height and depth vertical box and return it
float h = y.getHeight(), total = vBox.getHeight() + vBox.getDepth();
if (x != null)
h += bigop5 + kern + x.getHeight() + x.getDepth();
vBox.setHeight(h);
vBox.setDepth(total - h);
if (bbase != null) {
HorizontalBox hb = new HorizontalBox(bbase.createBox(env));
bbase.add(base);
hb.add(vBox);
base = Base;
return hb;
}
return vBox;
}
}
/*
* Centers the given box in a new box that has the given width
*/
private static Box changeWidth(Box b, float maxWidth) {
if (b != null && Math.abs(maxWidth - b.getWidth()) > TeXFormula.PREC)
return new HorizontalBox(b, maxWidth, TeXConstants.ALIGN_CENTER);
else
return b;
}
}