ElementWidth.java

package com.xenoage.zong.musiclayout.spacing;

import lombok.AllArgsConstructor;

import com.xenoage.utils.annotations.Const;
import com.xenoage.zong.core.music.MusicElement;

/**
 * This class stores the width of a {@link MusicElement},
 * that consists of a front gap, the symbol's width, a rear gap
 * and the lyric's width. All units are measured in
 * interline spaces.
 * 
 * The front gap is the gap for example needed for
 * accidentals and left-suspended notes.
 * 
 * The symbol's width is the total width of the symbol(s)
 * of the element. If it is for example a
 * chord with right-suspended notes, the width
 * is about two times the width of a single notehead.
 * If it is a chord with left-suspended notes,
 * the width is the same as the width of a single
 * notehead, because the left-suspended note was
 * already used for the front gap.
 * Also the dots of a chord belong to the
 * symbol's width.
 * 
 * The rear gap is the empty space behind the
 * symbol. Chords and rests use this gap to
 * illustrate their duration. The rear gap can often be shared
 * with the front gap of the following element, e.g. to
 * place grace notes.
 * 
 * The lyrics width is the amount of horizontal space
 * in interline spaces, which a lyric element needs
 * to be displayed (or, if there are more verses, it's
 * the width of the widest of these elements).
 *
 * @author Andreas Wenger
 */
@Const @AllArgsConstructor
public final class ElementWidth {

	/** The front gap in IS, or 0 if there is none. */
	public final float frontGap;
	/** The width of the symbol in IS. */
	public final float symbolWidth;
	/** The rear gap in IS, or 0 if there is none. */
	public final float rearGap;
	/** The width of the lyric in IS, or 0 if there is none. */
	public final float lyricWidth;

	/**
	 * Creates a new {@link ElementWidth}, which only has a
	 * symbol width but no front and rear gap and no lyric.
	 */
	public ElementWidth(float symbolWidth) {
		this(0, symbolWidth, 0, 0);
	}

	/**
	 * Creates a new {@link ElementWidth}, which has no lyric.
	 */
	public ElementWidth(float frontGap, float symbolWidth, float rearGap) {
		this(frontGap, symbolWidth, rearGap, 0);
	}

	/**
	 * Gets the overall width. This is the front gap plus the symbol's width
	 * plus the rear gap.
	 * Notice, that the lyric's width may be greater than this value.
	 */
	public float getWidth() {
		return frontGap + symbolWidth + rearGap;
	}

	/**
	 * Gets the used width. This is the front gap plus the symbol's width.
	 * Notice, that the lyric's width may be greater than this value.
	 */
	public float getUsedWidth() {
		return frontGap + symbolWidth;
	}

}