C graphics program to draw a line.

In this code snippet/program/example we will learn how to draw a line using programming using line() function of graphics.h header file?

In this example we will draw two horizontal lines using line() function of graphics.h.

line() in c programming:

line() is a library function of graphics.c in c programming language which is used to draw a line from two coordinates.

For example if you want to draw a line from point(x1,y1) to point(x2,y2) you have to use line() function like line(x1,y1,x2,y2);

Syntax (Declaration of line() function in C)

line(int x1,int y1, int x2,int y2);

C Code Snippet - Graphics program to Draw a line using line() and lineto()

Let’s consider the following example:

/*C graphics program to draw a line.*/

#include <graphics.h>
#include <conio.h>
 
main()
{
   int gd = DETECT, gm;
 
   //init graphics
   initgraph(&gd, &gm, "C:/TURBOC3/BGI");
   /*
   if you are using turboc2 use below line to init graphics:
   initgraph(&gd, &gm, "C:/TC/BGI");
   */

   //draw a line

   /*
   line() function description
   parameter left to right
   x1: 100
   y1: 100
   x2: 200
   y2: 100
   */
   line(100,100,200,100);    //will draw a horizontal line

   line(10,10,200,10); //will draw another horizonatl line

   getch();
   closegraph();
   return 0;
}

Output

Reference: http://www.programmingsimplified.com/c/graphics.h/line

Draw a line from current point to point(x,y) using lineto() function

lineto() is a library function of graphics.h and it can be used to draw a line from current point to specified point.

For example, if you want to draw a line from current point to point(x,y), you have to use lineto() function like lineto(x,y)

Syntax (Declaration of line() function in C)

lineto(int x, int y);

In this program we will draw a line from current point to point (100,200).

/*Draw a line from current point to 
point(x,y) using lineto() function*/

#include <graphics.h>
#include <conio.h>
 
main()
{
   int gd = DETECT, gm;
 
   //init graphics
   initgraph(&gd, &gm, "C:/TURBOC3/BGI");
   /*
   if you are using turboc2 use below line to init graphics:
   initgraph(&gd, &gm, "C:/TC/BGI");
   */

   //draw a line
   lineto(100,200); //will dra a line to point(100,200)

   getch();
   closegraph();
   return 0;
}

Output