画椭圆

[c]代码库

#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>

int main ( void )
{
	/* request auto detection */
	int gdriver = DETECT, gmode, errorcode;
	int midx, midy;
	int stangle = 0, endangle = 360;
	int xradius = 100, yradius = 50;

	/* initialize graphics, 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 */
	}

	midx = getmaxx() / 2;
	midy = getmaxy() / 2;
	setcolor ( getmaxcolor() );

	/* draw ellipse */
	ellipse ( midx, midy, stangle, endangle,
	          xradius, yradius );

	/* clean up */
	getch();
	closegraph();
	return 0;
}