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/* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana

 *

 * Copyright (C) 2005 IVER T.I. and Generalitat Valenciana.

 *

 * 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.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 *

 * For more information, contact:

 *

 *  Generalitat Valenciana

 *   Conselleria d'Infraestructures i Transport

 *   Av. Blasco Ib??ez, 50

 *   46010 VALENCIA

 *   SPAIN

 *

 *      +34 963862235

 *   gvsig@gva.es

 *      www.gvsig.gva.es

 *

 *    or

 *

 *   IVER T.I. S.A

 *   Salamanca 50

 *   46005 Valencia

 *   Spain

 *

 *   +34 963163400

 *   dac@iver.es

 */

/* CVS MESSAGES:

*

* $Id: TextPath.java 10679 2007-03-09 11:25:01Z jaume $

* $Log$

* Revision 1.2  2007-03-09 11:20:57  jaume

* Advanced symbology (start committing)

*

* Revision 1.1.2.3  2007/02/21 07:34:09  jaume

* labeling starts working

*

* Revision 1.1.2.2  2007/02/09 07:47:05  jaume

* Isymbol moved

*

* Revision 1.1.2.1  2007/02/06 17:01:04  jaume

* first version (only lines)

*

*

*/

package com.iver.cit.gvsig.fmap.core;

import java.awt.Font;

import java.awt.Graphics2D;

import java.awt.font.FontRenderContext;

import java.awt.font.GlyphVector;

import java.awt.geom.Point2D;

import org.apache.batik.ext.awt.geom.PathLength;

/**

 * <p>Class that represents baseline of a string and allows the baseline to

 * be composed as contiguous segments with distinct slope each.<br></p>

 *

 * <p>Once a TextPath is created for a string it is possible to know where

 * the character at a determined position in the string is placed and

 * rotated.<br></p>

 *

 * @author jaume dominguez faus - jaume.dominguez@iver.es

 *

 */

public class TextPath {

        private char[] text;

        private double[][] pos;

        /**

         * <p>Creates a new instance of TextPath with the current graphics

         * context.<br></p>

         *

         * <p>Given a <b>Graphics2D</b>, TextPath can know which Font and FontRenderContext

         * is in use. So, it can calculate the position and rotation of each

         * character in <b>char[] text</b> based in the path defined by the

         * <b>FShape path</b> argument.</p>

         * @param g, Graphics2D

         * @param path, FShape

         * @param text, char[]

         */

        public TextPath(Graphics2D g, FShape path, char[] text) {

                this.text = text;

                compute(g, path);

        }

        /**

         * Initializes the position vector.

         * @param g

         * @param path

         */

        private void compute(Graphics2D g, FShape path) {

                PathLength pl = new PathLength(path);

                Font font = g.getFont();

                FontRenderContext frc = g.getFontRenderContext();

                GlyphVector gv = font.createGlyphVector(frc, text);

                int numGlyphs = gv.getNumGlyphs();

                pos = new double[numGlyphs][3];

                double lineLength = pl.lengthOfPath() / numGlyphs;// - ( margin + margin )

                for (int i = 0; i < numGlyphs; i++) {

                        float charDistance = (float) lineLength*i;//(gv.getGlyphPosition(i).getX() * lineLength); // + margin

                        Point2D p = pl.pointAtLength(charDistance);

                        pos[i][0] = p.getX();

                        pos[i][1] = p.getY();

                        pos[i][2] = (double) pl.angleAtLength(charDistance);

                }

        }

        /**

         * <p>Returns the placement of the next character to draw and the corresponding

         * rotation in a double array of three elements with this order:</p><br>

         *

         * <p><b>double[0]</b> Position in X in the screen</p>

         * <p><b>double[1]</b> Position in Y in the screen</p>

         * <p><b>double[2]</b> Angle of the character.</p>

         * @return

         */

        public double[] nextPosForGlyph(int glyphIndex) {

                return pos[glyphIndex];

        }

}