drawpoly

Syntax

#include <graphics.h>

void drawpoly(int numpoints, int *polypoints);

Description

drawpoly draws a polygon with numpoints points, using the current line style and color.

*polypoints points to a sequence of (numpoints * 2) integers. Each pair of integers gives the x- and y-coordinates of a point on the polygon.

In order to draw a closed figure with n vertices, you must pass n + 1 coordinates to drawpoly where the nth coordinate is equal to the 0th.

Return Value

None.

See also

fillpoly

floodfill

graphresult

setwritemode

Example

/* drawpoly example */ 



#include <graphics.h>

#include <stdlib.h>

#include <stdio.h>

#include <conio.h>



int main(void)

{

   /* request autodetection */

   int gdriver = DETECT, gmode, errorcode;

   int maxx, maxy;



   int poly[10];   /* our polygon array */



   /* initialize graphics and local variables */

   initgraph(&gdriver, &gmode, "");



   /* read result of initialization */

   errorcode = graphresult();

   if (errorcode != grOk){ /* an error occurred */

      printf("Graphics error: %s\n", grapherrormsg(errorcode));



      printf("Press any key to halt:");

      getch();

      exit(1);             /* terminate with an error code */

   }



   maxx = getmaxx();

   maxy = getmaxy();

   poly[0] = 20;           /* first vertex */

   poly[1] = maxy / 2;

   poly[2] = maxx - 20;    /* second vertex */

   poly[3] = 20;

   poly[4] = maxx - 50;    /* third vertex */

   poly[5] = maxy - 20;

   poly[6] = maxx / 2;     /* fourth vertex */

   poly[7] = maxy / 2;

   poly[8] = poly[0];      /* drawpoly doesn't automatically close */



   poly[9] = poly[1];      /* the polygon, so we close it */



   drawpoly(5, poly);   /* draw the polygon */



   /* clean up */

   getch();

   closegraph();

   return 0;

}