Draw a triangle in C++ graphics

Last Updated : 02 Sep, 2020

Prerequisite: graphics.h, How to include graphics.h in CodeBlocks?

The task is to write a C program to make a triangle with the line function of graphics.

To run the program we have to include the below header file:

#include <graphic.h>

Approach: The idea is to create a triangle with the help of several lines. We will draw a line in graphics by passing 4 numbers to line() function as:

line(a, b, c, d)
The above function will draw a line from coordinates (a, b) to (c, d) in the output window.

Below is the implementation of the above approach:

C++

// C++ program for drawing a triangle 
#include <graphics.h> 
#include <iostream> 
  
// Driver code 
int main() 
{ 
    // gm is Graphics mode which 
    // is a computer display 
    // mode that generates 
    // image using pixels. 
    // DETECT is a macro 
    // defined in "graphics.h" 
    // header file 
    int gd = DETECT, gm; 
  
    // initgraph initializes 
    // the graphics system 
    // by loading a graphics 
    // driver from disk 
    initgraph(&gd, &gm, ""); 
  
    // Triangle 
  
    // line for x1, y1, x2, y2 
    line(150, 150, 450, 150); 
  
    // line for x1, y1, x2, y2 
    line(150, 150, 300, 300); 
  
    // line for x1, y1, x2, y2 
    line(450, 150, 300, 300); 
  
    // closegraph function closes 
    // the graphics mode and 
    // deallocates all memory 
    // allocated by graphics system 
    getch(); 
  
    // Close the initialized gdriver 
    closegraph(); 
} 