/**************************************************************************
/* This class is part of the Java Plotlib Toolkit.
/*
/* Copyright (c) 1999-2004 by Bernhard Bablok (mail@bablokb.de)
/*
/* 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 Library General Public License for more details.
/*
/* You should have received a copy of the GNU General Public License
/* along with this program; see the file COPYING.  If not, write to
/* the Free Software Foundation Inc., 59 Temple Place - Suite 330,
/* Boston, MA  02111-1307 USA
/**************************************************************************/
package de.bablokb.plotlib.core;

import java.awt.*;
import java.awt.geom.*;

/**
   Define symbol-forms. Symbol constants are defined in class Plotlib.

   Subclasses of Form implement the actual drawing necessary to plot the
   symbol defined by the corresponding symbol type. To add a new symbol,
   you must subclass Form, add a type constant to the Plotlib class and
   change the mapping array of type constants in Plotlib.FORM_TABLE.

   @see de.bablokb.plotlib.core.Plotlib

   @version $Revision: 1.3 $
   @author  $Author: bablokb $

*/

abstract class Form {

  /**
     Size of the form.
  */

  protected float iSize;

  /**
     Graphics2D object to draw to.
  */

  protected Graphics2D iG2 = null;

  /////////////////////////////////////////////////////////////////////////////

  /**
     Set the Graphics2D object.
  */

  public void setG2(Graphics2D g2) {
    iG2 = g2;
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Set size of the form.
  */

  public void setSize(float size) {
    iSize = size;
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Plot the form. This method must be implemented by subclasses.
  */

  public abstract void plot(Point2D p);

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws a circle.
  */

  static class Circle extends Form {

    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 

       <p><strong>FIXME:</strong> Use Ellipse2D instead of Arc2D and take
       the aspect ratio into account to make the circle a circle.
    */

    public void plot(Point2D p) {
      Arc2D a = Toolkit.getDefaultToolkit().getArc2D();
      a.setArcByCenter(p.getX(),p.getY(),iSize/2,0,360,Arc2D.OPEN);
      iG2.draw(a);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws a minus sign.
  */

  static class Minus extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/2,y);
      gp.lineTo(x+iSize/2,y);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////


  /**
     Draws a plus sign.
  */

  static class Plus extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/2,y);
      gp.lineTo(x+iSize/2,y);
      gp.moveTo(x,y-iSize/2);
      gp.lineTo(x,y+iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws a star.
  */

  static class Star extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/2,y);
      gp.lineTo(x+iSize/2,y);
      gp.moveTo(x,y-iSize/2);
      gp.lineTo(x,y+iSize/2);
      gp.moveTo(x-iSize/2,y-iSize/2);
      gp.lineTo(x+iSize/2,y+iSize/2);
      gp.moveTo(x-iSize/2,y+iSize/2);
      gp.lineTo(x+iSize/2,y-iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws a square.
  */

  static class Square extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/2,y+iSize/2);
      gp.lineTo(x+iSize/2,y+iSize/2);
      gp.lineTo(x+iSize/2,y-iSize/2);
      gp.lineTo(x-iSize/2,y-iSize/2);
      gp.lineTo(x-iSize/2,y+iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws a vertical bar.
  */

  static class Vert extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x,y-iSize/2);
      gp.lineTo(x,y+iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws an arrow pointing south. The GeneralPath takes the standard
     orientation of y-coordinates into account (top to bottom).
  */

  static class SArrow extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/4,y-iSize/2);
      gp.lineTo(x,y);
      gp.lineTo(x+iSize/4,y-iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws an arrow pointing east.
  */

  static class EArrow extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/2,y-iSize/4);
      gp.lineTo(x,y);
      gp.lineTo(x-iSize/2,y+iSize/4);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws an arrow pointing north.  The GeneralPath takes the standard
     orientation of y-coordinates into account (top to bottom).
  */

  static class NArrow extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x-iSize/4,y+iSize/2);
      gp.lineTo(x,y);
      gp.lineTo(x+iSize/4,y+iSize/2);
      iG2.draw(gp);
    }
  }

  /////////////////////////////////////////////////////////////////////////////
  /////////////////////////////////////////////////////////////////////////////

  /**
     Draws an arrow pointing west.
  */

  static class WArrow extends Form {
    
    ///////////////////////////////////////////////////////////////////////////

    /**
       Plot the form. 
    */

    public void plot(Point2D p) {
      GeneralPath gp = new GeneralPath();
      float x = (float) p.getX(), y = (float) p.getY();
      gp.moveTo(x+iSize/2,y-iSize/4);
      gp.lineTo(x,y);
      gp.lineTo(x+iSize/2,y+iSize/4);
      iG2.draw(gp);
    }
  }
}