//      Pie chart demo.
//

#include "plcdemos.h"

static const char *text[] =
{
    "Maurice",
    "Geoffrey",
    "Alan",
    "Rafael",
    "Vince"
};

//--------------------------------------------------------------------------
// main
//
// Does a simple pie chart.
//--------------------------------------------------------------------------

int
main( int argc, const char *argv[] )
{
    int          i, j, dthet, theta0, theta1, theta;
    PLFLT        just, dx, dy;
    static PLFLT x[500], y[500], per[5];

    per[0] = 10.;
    per[1] = 32.;
    per[2] = 12.;
    per[3] = 30.;
    per[4] = 16.;

// Parse and process command line arguments

    (void) plparseopts( &argc, argv, PL_PARSE_FULL );

// Initialize plplot

    plinit();

    pladv( 0 );
    // Ensure window has aspect ratio of one so circle is
    // plotted as a circle.
    plvasp( 1.0 );
    plwind( 0., 10., 0., 10. );
    // plenv(0., 10., 0., 10., 1, -2);
    plcol0( 2 );
    // n.b. all theta quantities scaled by 2*M_PI/500 to be integers to avoid
    // floating point logic problems.
    theta0 = 0;
    dthet  = 1;
    for ( i = 0; i <= 4; i++ )
    {
        j      = 0;
        x[j]   = 5.;
        y[j++] = 5.;
        // n.b. the theta quantities multiplied by 2*M_PI/500 afterward so
        // in fact per is interpreted as a percentage.
        theta1 = (int) ( theta0 + 5 * per[i] );
        if ( i == 4 )
            theta1 = 500;
        for ( theta = theta0; theta <= theta1; theta += dthet )
        {
            x[j]   = 5 + 3 * cos( ( 2. * M_PI / 500. ) * theta );
            y[j++] = 5 + 3 * sin( ( 2. * M_PI / 500. ) * theta );
        }
        plcol0( i + 1 );
        plpsty( ( i + 3 ) % 8 + 1 );
        plfill( j, x, y );
        plcol0( 1 );
        plline( j, x, y );
        just = ( 2. * M_PI / 500. ) * ( theta0 + theta1 ) / 2.;
        dx   = .25 * cos( just );
        dy   = .25 * sin( just );
        if ( ( theta0 + theta1 ) < 250 || ( theta0 + theta1 ) > 750 )
            just = 0.;
        else
            just = 1.;

        plptex( ( x[j / 2] + dx ), ( y[j / 2] + dy ), 1.0, 0.0, just, text[i] );
        theta0 = theta - dthet;
    }
    plfont( 2 );
    plschr( 0., 1.3 );
    plptex( 5.0, 9.0, 1.0, 0.0, 0.5, "Percentage of Sales" );

// Don't forget to call PLEND to finish off!

    plend();
    exit( 0 );
}
