Comments by Amjad Kherbeck (Top 8 by date)

#include<stdio.h>
#include<conio.h>
#include<dos.h>
#include<graphics.h>
#include<stdlib.h>
typedef struct coord
{
int x,y;
char code[4];
}PT;
void drawwindow();
void drawline(PT p1,PT p2,int c1);
PT setcode(PT p);
int visibility(PT p1,PT p2);
PT resetendpt(PT p1,PT p2);
void main()
{
int gd=DETECT,gm,v;
PT p1,p2,ptemp;
initgraph(&gd,&gm,"");
cleardevice();
printf("\t\tCOHEN-SUTHERLAND LINE CLIPPING ALGORITHM");
printf("\nEnter the two end points p1(x,y)");
scanf("%d%d",&p1.x,&p1.y);
printf("Enter the two end points p2(x,y):");
scanf("%d%d",&p2.x,&p2.y);
cleardevice();
printf("\t\tCLIPPING WINDOW");
drawwindow();
getch();
printf("\tCOHEN-SUTHERLAND LINE CLIPPING ALGORITHM");
printf("\n\t\tBEFORE CLIPPING");
drawline(p1,p2,4);
getch();
p1=setcode(p1);
p2=setcode(p2);
v=visibility(p1,p2);
switch(v)
{
case 0:
cleardevice();
//printf("\t\tCLIPPING WINDOW");
drawwindow();
drawline(p1,p2,15);
break;
case 1:
cleardevice();
drawwindow();
break;
case 2:
cleardevice();
p1=resetendpt(p1,p2);
p2=resetendpt(p2,p1);
drawwindow();
printf("\tCOHEN-SUTHERLAND LINE CLIPPING ALGORITHM");
printf("\n\t\tAFTER CLIPPING");
drawline(p1,p2,15);
break;
}
getch();
closegraph();
//return(0);
}
void drawwindow()
{
setcolor(RED);
setlinestyle(DOTTED_LINE, 1, 1);
line(150,100,100,100);
line(150,100,150,50);
line(450,100,500,100);
line(450,100,450,50);
line(450,350,500,350);
line(450,350,450,400);
line(150,350,150,400);
line(150,350,100,350) ;
line(150,100,100,100);
line(150,100,150,50);
setlinestyle(SOLID_LINE, 1, 1);
line(150,100,450,100);
line(450,100,450,350);
line(450,350,150,350);
line(150,350,150,100);

outtextxy(450,30,"1001");
outtextxy(470,200,"1000");
outtextxy(470,370,"1010");
outtextxy(300,370,"0010");
outtextxy(120,370,"0110");
outtextxy(120,200,"0100");
outtextxy(120,30,"0101");
outtextxy(300,30,"0001");
outtextxy(300,200,"0000");
}
void drawline(PT p1,PT p2,int c1)
{
setcolor(c1);
line(p1.x,p1.y,p2.x,p2.y);
}

PT setcode(PT p)
{
PT ptemp;
if(p.y<100)
ptemp.code[0]='1';
else
ptemp.code[0]='0';
if(p.y>350)
ptemp.code[1]='1';
else
ptemp.code[1]='0';
if(p.x>200)
ptemp.code[2]='1';
else
ptemp.code[2]='0';
if(p.x<150)
ptemp.code[3]='1';
else
ptemp.code[3]='0';
ptemp.x=p.x;
ptemp.y=p.y;
return(ptemp);
}
int visibility(PT p1,PT p2)
{
int i,flag=0;
for(i=0;i<4;i++)
{
if((p1.code[i]!='0')||(p2.code[i]!='0'))
flag=1;
}
if(flag==0)
return(0);
for(i=0;i<4;i++)
{
if((p1.code[i]==p2.code[i])&&(p1.code[i]=='1'))
flag=0;
}
if(flag==0)
return(1);
return(2);
}
PT resetendpt(PT p1,PT p2)
{
PT temp;
int x,y,i;
float m,k;
if(p1.code[3]=='1')
x=150;
if(p1.code[2]=='1')
x=450;
if((p1.code[3]=='1')||(p1.code[2]=='1'))
{
m=(float)(p2.y-p1.y)/(p2.x-p1.x);
k=(p1.y+(m*(x-p1.x)));
temp.y=k;
temp.x=x;
for(i=0;i<4;i++)
{
temp.code[i]=p1.code[i];
if(temp.y<=350 && temp.y>=100)
return(temp);
}
if(p1.code[0]=='1')
y=100;
if(p1.code[1]=='1')
y=350;
if((p1.code[0]=='1')||(p1.code[1]=='1'))
{
m=(float)(p2.y-p1.y)/(p2.x-p1.x);
k=(float)p1.x+(float)(y-p1.y)/m;
temp.y=y;
temp.x=k;
for(i=0;i<4;i++)
temp.code[i]=p1.code[i];
return(temp);
}
}
else
return(p1);
return(p2);
}
i tried this but it didnt work