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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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package com.sun.javafx.tk;

import javafx.scene.text.Font;

The metrics for a Font, including helper functions for computing string
width/height and other metrics based on a specific String of text with
this font.
/**
 * The metrics for a Font, including helper functions for computing string
 * width/height and other metrics based on a specific String of text with
 * this font.
 */
public class FontMetrics {

    public static FontMetrics createFontMetrics(
            float maxAscent, float ascent, float xheight, float descent,
            float maxDescent, float leading, Font font) {
        return new FontMetrics(maxAscent, ascent, xheight, descent, maxDescent, leading, font);
    }

    
The distance from the baseline to the max character height.
This value is always positive
/**
     * The distance from the baseline to the max character height.
     * This value is always positive
     */
    private float maxAscent;

    public final float getMaxAscent() {
        return maxAscent;
    }

    
The distance from the baseline to the avg max character height.
this value is always positive
/**
     * The distance from the baseline to the avg max character height.
     * this value is always positive
     */
    private float ascent;

    public final float getAscent() {
        return ascent;
    }

    
The distance from the baseline to the top of the avg. lowercase letter.
/**
     * The distance from the baseline to the top of the avg. lowercase letter.
     */
    private float xheight;

    public final float getXheight() {
        return xheight;
    }

    
The baseline is the imaginary line upon which letters without descenders
(for example, the lowercase letter "a") sits. In terms of the font
metrics, all other metrics are derived from this point. This point is
implicitly defined as zero.
/**
     * The baseline is the imaginary line upon which letters without descenders
     * (for example, the lowercase letter "a") sits. In terms of the font
     * metrics, all other metrics are derived from this point. This point is
     * implicitly defined as zero.
     */
    private int baseline;

    public final int getBaseline() {
        return baseline;
    }

    
The distance from the baseline down to the lowest avg. descender. This
value is always positive
/**
     * The distance from the baseline down to the lowest avg. descender. This
     * value is always positive
     */
    private float descent;

    public final float getDescent() {
        return descent;
    }

    
The distance from the baseline down to the absolute lowest descender.
this value is always positive
/**
     * The distance from the baseline down to the absolute lowest descender.
     * this value is always positive
     */
    private float maxDescent;

    public final float getMaxDescent() {
        return maxDescent;
    }

    
The amount of space between lines of text in this font. This is the
amount of space between he maxDecent of one line and the maxAscent
of the next. This number is included in the lineHeight.
/**
     * The amount of space between lines of text in this font. This is the
     * amount of space between he maxDecent of one line and the maxAscent
     * of the next. This number is included in the lineHeight.
     */
    private float leading;

    public final float getLeading() {
        return leading;
    }

    
The maximum line height for a line of text in this font
/**
     * The maximum line height for a line of text in this font
     */
    private float lineHeight;

    public final float getLineHeight() {
        return lineHeight;
    }

    
The font that was used to construct these metrics.
/**
     * The font that was used to construct these metrics.
     */
    private Font font;

    public final Font getFont() {
        if (font == null) {
            font = Font.getDefault();
        }
        return font;
    }

    public FontMetrics(
            float maxAscent, float ascent, float xheight, float descent,
            float maxDescent, float leading, Font font) {
        this.maxAscent = maxAscent;
        this.ascent = ascent;
        this.xheight = xheight;
        this.descent = descent;
        this.maxDescent = maxDescent;
        this.leading = leading;
        this.font = font;
        lineHeight = maxAscent + maxDescent + leading;
    }

    
Computes the width of the char when rendered with the font represented
by this FontMetrics instance.
/**
     * Computes the width of the char when rendered with the font represented
     * by this FontMetrics instance.
     */
    public float getCharWidth(char ch) {
        return Toolkit.getToolkit().getFontLoader().getCharWidth(ch, getFont());
    }

    @Override public String toString() {
        return "FontMetrics: [maxAscent=" + getMaxAscent()
            + ", ascent=" + getAscent()
            + ", xheight=" + getXheight()
            + ", baseline=" + getBaseline()
            + ", descent=" + getDescent()
            + ", maxDescent=" + getMaxDescent()
            + ", leading=" + getLeading()
            + ", lineHeight=" + getLineHeight()
            + ", font=" + getFont() + "]";
    }
}