# examples/arithmetic.cpp

    /*
     * @file   arithmetic.cpp
     * @author Sebastien Fourey <http://www.greyc.ensicaen.fr/~seb>
     * @date   Tue Aug 21
     *
     * @brief  Example that shows the usage of the Board library by
     * illustating the arithmetic coding principle.
     * <p>Files arithm.eps, arithm.fig and arithm.svg are created in the current directory.</p>
     *
     * This source code is part of the Board project, a C++ library whose
     * purpose is to allow simple drawings in EPS, FIG or SVG files.
     * Copyright (C) 2007 Sebastien Fourey <http://www.greyc.ensicaen.fr/~seb/>
     */
    /*
     * @file   arithmetic.cpp
     * @author Sebastien Fourey <http://www.greyc.ensicaen.fr/~seb>
     * @date   Tue Aug 21
     *
     * @brief  Example that shows the usage of the Board library by
     *         illustating the arithmetic coding principle.
     *         Files arithm.eps, arithm.fig and arithm.svg are created in
     *         the current directory.
     *
     */
    #include "Board.h"
    #include <cstdlib>
    #include <iostream>
    #include <fstream>
    #include <cmath>
    #include <cstring>
    using namespace std;
    using namespace LibBoard;

    int main( int argc, char *argv[] )
    {
      Board board;

      if ( argc == 2 && !strcmp(argv[1],"-h") ) {
        cout << "Usage:   arithmetic [word] \n\n  Where word has letters in {a, b, c, d, e}\n\n";
        exit(0);
      }

      char the_string[1024];
      secured_strncpy( the_string, "cccccccbb", 1024 );

      if ( argc == 2 ) {
        secured_strncpy( the_string, argv[1], 1024 );
      }

      // char letters[] = "abcde";
      double proba[100] = { 0.2, 0.1, 0.6, 0.05, 0.05 };
      double lefts[100] = { 0, 0.2, 0.3, 0.9, 0.95  };
      Color colors[5] = { Color( 0, 0, 255 ),
                          Color( 0, 255, 0 ),
                          Color( 255, 0, 0 ),
                          Color( 0, 255, 255 ),
                          Color( 255, 255, 0 ) };

      char *pc = the_string;
      int h = 0;
      double thickness = 0.5 / strlen( the_string );

      board.drawRectangle( 0, 0, 1.0, 0.5 );

      double left = 0;
      double width = 1.0;
      double w = 1.0;
      double n = 1;
      char str[20];

      board.setLineWidth( 0.1 );
      board.clear( Color( 230, 230, 230 ) );
      while ( *pc ) {
        int i = *pc - 'a';
        left += width * lefts[ i ];
        width *= proba[i];

        board.setPenColorRGBi( 100, 100, 100 );
        w /= 2.0;
        n *= 2;
        for ( int k = 0; k < n; k++ )
          board.drawRectangle( k*w, -h * thickness, w, 0.9*thickness );

        board.setPenColor( colors[ i ] );
        board.drawRectangle( left, -h * thickness, width, 0.9*thickness );

        secured_sprintf( str, 20, "%c", *pc );
        board.drawText( (left + width/2.0 ), -(h+0.5) * thickness, str );
        ++h;
        ++pc;
      }

      // Draw the letters rectangles.
      for ( int k = 0; k < 5; k++ ) {
        board.setPenColor( colors[ k ] );
        board.drawRectangle( lefts[k], thickness, proba[k], 0.9*thickness );
        secured_sprintf( str, 20, "%c", 'a' + k  );
        //board.drawText( lefts[k] + proba[k]/2.0, 0.5*thickness, str );
      }

      board.save( "arithm.eps", Board::A4 );
      board.save( "arithm.fig", Board::A4 );
      board.save( "arithm.svg", Board::A4 );
      exit(0);
    }