110 lines
1.7 KiB
C++
110 lines
1.7 KiB
C++
#include<iostream>
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#include<graphics.h>
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#include<math.h>
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#include<cstdlib>
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using namespace std;
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static int LEFT = 1, RIGHT = 2, BOTTOM = 4, TOP = 8, xmax,ymax,xmin,ymin;
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int getcode(int x,int y)
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{
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int code = 0;
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if(y>ymax) code |= TOP;
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if(y<ymin) code |= BOTTOM;
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if(x<xmin) code |= LEFT;
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if(x>xmax) code |= RIGHT;
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return code;
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}
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int main()
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{
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int gd = DETECT,gm;
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initgraph(&gd,&gm,NULL);
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int x1,y1,x2,y2;
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cout<<"Enter top left and bottom right coordinates: ";
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cin>>xmin>>ymin>>xmax>>ymax;
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cout<<"Enter endpoints of line: ";
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cin>>x1>>y1>>x2>>y2;
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//outtext("Before clipping");
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rectangle(xmin,ymin,xmax,ymax);
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line(x1,y1,x2,y2);
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delay(10000);
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int outcode1 = getcode(x1,y1);
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int outcode2 = getcode(x2,y2);
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int accept = 0;
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while(1)
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{
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float m = (float)(y2-y1)/(x2-x1);
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if(outcode1==0 && outcode2==0)
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{
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accept = 1;
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break;
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}
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else if((outcode1 & outcode2)!= 0)
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{
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break;
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}
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else
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{
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int x,y;
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int temp;
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if(outcode1 == 0)
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{
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temp = outcode2;
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}
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else
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{
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temp = outcode1;
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}
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if(temp & TOP)
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{
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x = x1 + (ymax - y1)/m;
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y = ymax;
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}
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else if(temp & BOTTOM)
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{
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x = x1 + (ymin - y1)/m;
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y = ymin;
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}
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else if(temp & LEFT)
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{
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x = xmin;
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y = y1 + m*(xmin - x1);
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}
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else if(temp & RIGHT)
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{
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x = xmax;
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y = y1 + m*(xmax - x1);
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}
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if(temp == outcode1)
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{
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x1 = x;
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y1 = y;
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outcode1 = getcode(x1,y1);
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}
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else
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{
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x2 = x;
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y2 = y;
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outcode2 = getcode(x2,y2);
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}
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}
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}
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setcolor(BROWN);
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if(accept)
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{
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cleardevice();
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//outtext("After clipping");
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rectangle(xmin,ymin,xmax,ymax);
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line(x1,y1,x2,y2);
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}
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else
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{
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cleardevice();
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//outtext("After clipping");
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rectangle(xmin,ymin,xmax,ymax);
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}
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getch();
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closegraph();
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return 0;
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}
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