C Program to Draw Bezier Curve - Graphics Lab Program

This is a c program to draw a bezier curve. You can draw a bezier curve by giving control points. The control points' co-ordinates are stored in arrays x[] and y[]. You can draw different curves by combining multiple bezier curves. We will see such examples in some other posts. Here, this program has a function named bezier which draws the curve using an array of control points declared globally.

#include <stdio.h>
#include <graphics.h>
#include <math.h>

int x[4]={200,100,200,250};
int y[4]={200,150,75,100};

void bezier ()
{

int i;
double t,xt,yt;

for (t = 0.0; t < 1.0; t += 0.0005)
{
xt = pow(1-t,3)*x[0]+3*t*pow(1-t,2)*x[1]+3*pow(t,2)*(1-t)*x[2]+pow(t,3)*x[3];
yt = pow(1-t,3)*y[0]+3*t*pow(1-t,2)*y[1]+3*pow(t,2)*(1-t)*y[2]+pow(t,3)*y[3];
putpixel (xt, yt,WHITE);
}

for (i=0; i<4; i++)
 putpixel (x[i], y[i], YELLOW);
getch();
closegraph();
}
 
void main()
{
int gd = DETECT, gm;
initgraph (&gd, &gm, "..\\bgi");
bezier ();
}