Graphics in C

In a C Program first of all you need to initialize the graphics drivers on the computer. This is done using the initgraph method provided in graphics.h library.

Graphics mode Initialization:
initgraph() function is used to load the graphics drivers and initialize the graphics system. For every function, that uses graphics mode, graphics mode must be initialized before using that function.

void far initgraph(int far *driver, int far *mode, char far *path)

Function detectgraph:
Detectgraph function determines the graphics hardware in the system, if the function finds a graphics adapter then it returns the highest graphics mode that the adapter supports.

void far detectgraph(int far *driver, int far *mode)

Integer that specifies the graphics driver to be used. You can give graphdriver a value using a constant of the graphics_drivers enumeration type.

Graphic Mode:
Integer that specifies the initial graphics mode (unless *graphdriver = DETECT). If *graphdriver = DETECT, initgraph sets *graphmode to the highest resolution available for the detected driver. You can give *graphmode a value using a constant of the graphics_modes enumeration type.


Function closegraph:
This function shutdown the graphics mode and returns to the position it was before the initgraph function was called.
void far closegraph(void)


Example 1:

#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>

void main()
{
    int gd=DETECT, gm;

    initgraph(&gd, &gm, "c:\\turboc\\bgi");
    circle(200,100,150);

    getch();

  closegraph();
}


Example 2:

#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>


void main()
{
    int gd=DETECT, gm;
    initgraph(&gd, &gm, " c:\\turboc\\bgi");
     
    circle(100,100,50);
    outtextxy(75,170, "Circle");
    rectangle(200,50,350,150);
    outtextxy(240, 170, "Rectangle");
    ellipse(500, 100,0,360, 100,50);
    outtextxy(480, 170, "Ellipse");
    line(100,250,540,250);
    outtextxy(300,260,"Line");

getch();
closegraph();
}


Some Useful Graphics.h Functions:

int getdisplaycolor( int color );
int converttorgb( int color );
void delay( int msec );
void getarccoords( arccoordstype *arccoords );
int getbkcolor( );
int getcolor( );
int getmaxcolor( );
int getmaxheight( );
int getmaxwidth( );
int getmaxx( );
int getmaxy( );
void getfillpattern( char *pattern );
void getfillsettings( fillsettingstype *fillinfo );
void getlinesettings( linesettingstype *lineinfo );
bool getrefreshingbgi( );
int getwindowheight( );
int getwindowwidth( );
int getpixel( int x, int y );
void getviewsettings( viewporttype *viewport );
int getx( );
int gety( );
void setcolor( int color );
void setfillpattern( char *upattern, int color );
void setfillstyle( int pattern, int color );
void setlinestyle( int linestyle, unsigned upattern, int thickness );
void setrefreshingbgi(bool value);
void setviewport( int left, int top, int right, int bottom, int clip );
void setwritemode( int mode );
void moverel( int dx, int dy );
void moveto( int x, int y );
void refreshbgi(int left, int top, int right, int bottom);
void refreshallbgi( );  
void setbkcolor( int color );