Question

2) You are given the task of finding a representation for a circle in a drawing application. The circle is to be displayed on the screen, and the user can edit the location and the radius of the circle, both of which are expressed in units of pixels.

a) Specify a data representation for the circle, trying to minimize the number of bits required.

b) Describe how data processing would draw a circle on the screen, starting with stored data, following your representation.

Answer 1

The header file graphics.h contains circle() function which draws a circle with center at (x, y) and given radius.

Syntax :

circle(x, y, radius);

where,
(x, y) is center of the circle.
'radius' is the Radius of the circle.

Examples :

Input : x = 250, y = 200, radius = 50
Output : 

Input : x = 300, y = 150, radius = 90
Output : 

// C Implementation for drawing circle

#include <graphics.h>

  //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, "");

  

    // circle fuction

    circle(250, 200, 50);

      getch();

      // closegraph function closes the graphics mode and deallocates all memory allocated by graphics system .

    closegraph();

      return 0;

}