Bresenham circle drawing algorithm.cpp

/* C++ program for circle drawing
using Bresenham’s Algorithm
in computer-graphics */
#include <stdio.h>
#include <graphics.h>
 
/*Function to put pixels
at subsequence points*/
void drawCircle(int xc, int yc, int x, int y)
{
    putpixel(xc+x, yc+y, RED);
    putpixel(xc-x, yc+y, RED);
    putpixel(xc+x, yc-y, RED);
    putpixel(xc-x, yc-y, RED);
    putpixel(xc+y, yc+x, RED);
    putpixel(xc-y, yc+x, RED);
    putpixel(xc+y, yc-x, RED);
    putpixel(xc-y, yc-x, RED);
}
 
/*Function for circle-generation
using Bresenham's algorithm*/
void circleBres(float xc, int yc, int r)
{
    int x = 0, y = r;
    int d = 3 - 2 * r;
    drawCircle(xc, yc, x, y);
    while (y >= x)
    {
        /* for each pixel we will
        draw all eight pixels */
         
        x++;
 
        /*check for decision parameter
        and correspondingly
        update d, x, y*/
        if (d > 0)
        {
            y--;
            d = d + 4 * (x - y) + 10;
        }
        else
            d = d + 4 * x + 6;
        drawCircle(xc, yc, x, y);
        delay(50);
    }
    getch();
}
 
 
// Driver code
int main()
{
	float xc,yc,r;
	/*Getting User input */
	printf("Enter the value of xc: ");  
    scanf("%f", &xc);
    printf("Enter the value of yc: ");  
    scanf("%f", &yc);
    printf("Enter the value of r: ");  
    scanf("%f", &r);
    int gd = DETECT, gm;
    initgraph(&gd, &gm, "");  // initialize graph
    circleBres(xc, yc, r);    // function call
    system("cls");
    return 0;
}