Q51654: Use _pg_setpalette() to Modify the Plot Characters

Article: Q51654
Product(s): See article
Version(s): 2.00
Operating System(s): MS-DOS
Keyword(s): ENDUSER | presentation graphics pgchart | mspl13_c
Last Modified: 17-JAN-1990

To modify the default character used for plotting line and scatter
charts, use the _pg_getpalette() and _pg_setpalette() functions. These
functions expect a variable of type palettetype, which is an array of
structures (defined in pgchart.h). Palettes are discussed in Section
3.4 of the "Microsoft QuickC Graphics Library Reference" manual for
Version 2.00. Below is an an example of how to use _pg_setpalette to
modify the default plot character for single and multiseries charts.

/* PLOTCHAR.C - Modifies the default plotting characters.      */
/* Note: To modify the array, start with index 1 -- see below. */

#include <conio.h>
#include <graph.h>
#include <string.h>
#include <stdlib.h>
#include <pgchart.h>

#define ITEMS  5
#define SERIES 2
float far employees[SERIES][ITEMS] = {{235.0F, 423.0F, 596.0F,
                                       729.0F, 963.0F},
                                      {285.0F, 392.0F, 634.0F,
                                       801.0F, 895.0F}};

float far profits[SERIES][ITEMS] =   {{0.9F,  2.3F,  5.4F,
                                       8.0F,  9.3F},
                                      {4.2F,  3.4F,  3.6F,
                                       2.9F,  2.7F}};

char far *companies[SERIES] = { "Goodstuff, Inc.", "Badjunk & Co."};

/* This type is defined in pgchart.h */
palettetype pal ;

void main( void )
{
    chartenv env;
    short mode = _VRES16COLOR;

    while( !_setvideomode( mode ) )
        mode--;
    if (mode == _TEXTMONO )
        exit( 1 );

    _pg_initchart();

    /* Single-series scatter chart */

    _pg_defaultchart (&env, _PG_SCATTERCHART, _PG_POINTONLY );
    strcpy( env.maintitle.title, "Goodstuff, Inc." );
    strcpy( env.xaxis.axistitle.title, "Employees" );
    strcpy( env.yaxis.axistitle.title, "Profitability" );

    /* Get old palette and modify plotchar for first series */
    _pg_getpalette( pal ) ;
    pal[1].plotchar = '+' ;
    _pg_setpalette( pal ) ;

    _pg_chartscatter( &env, employees[0], profits[0], ITEMS );
    getch();
    _clearscreen( _GCLEARSCREEN );

    /* Multi-series scatter chart */

    _pg_defaultchart (&env, _PG_SCATTERCHART, _PG_POINTONLY );
    strcpy( env.xaxis.axistitle.title, "Employees" );
    strcpy( env.yaxis.axistitle.title, "Profitability" );

    /* Get old palette and modify plotchar for second series */
    _pg_getpalette( pal ) ;
    pal[2].plotchar = 'X' ;
    _pg_setpalette( pal ) ;
    _pg_chartscatterms( &env, (float far *)employees,
                        (float far *)profits, SERIES, ITEMS, ITEMS,
                        companies );
    getch();

    exit( !_setvideomode( _DEFAULTMODE ) );
}