Program to draw a line using Bresenham’s line drawing algorithm

//Program to draw a line using Bresenham’s line drawing algorithm

#include

#include

#include

#include

void bresen(int,int,int,int);

void main()

{

int gdriver=DETECT,gmode;

int x1,x2,y1,y2;

clrscr();

printf("\nEnter coordinates of end points : ");

printf("\nx1 : ");scanf("%d",&x1);

printf("y1 : ");scanf("%d",&y1);

printf("x2 : ");scanf("%d",&x2);

printf("y2 : ");scanf("%d",&y2);

initgraph(&gdriver,&gmode,"e:\\tc\\bgi");

bresen(x1,y1,x2,y2);

getch();

}

void bresen(int x1,int y1,int x2,int y2)

{

int dx,dy,p,twoDy,twoDyDx,x,y,xEnd;

dx=abs(x2-x1); dy=abs(y2-y1);

p=2*dy-dx;

twoDy=2*dy;

twoDyDx=2*(dy-dx);

if(x1>x2)

{

x=x2;

y=y2;

xEnd=x1;

}

else

{

x=x1;

y=y1;

xEnd=x2;

}

putpixel(x,y,WHITE);

while(x

{

x++;

if(p<0)

p+=twoDy;

else

{

y++;

p+=twoDyDx;

}

putpixel(x,y,WHITE);

}

}