Polygon Clipping(Sutherland Hodgeman) C++ code free download

Given below is C code for Sutherland Hodgeman Polygon clipping algorithm.
//Sutherland Hodgeman Polygon clipping BY ADITYA MANDHARE #include<iostream.h> #include<conio.h> #include <graphics.h> #include <stdlib.h> #include <stdio.h> #include <conio.h> #include<dos.h> int px[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int py[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int lx[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int ly[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int rx[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int ry[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int bx[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int by[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int tx[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; int ty[]={0,0,0,0,0,0,0,0,0,0,0,0,0}; float m[12]; int getx(int,float,int); int gety(int,float,int); int c=0; void main() { int gdriver = DETECT, gmode; initgraph(&gdriver, &gmode, "c:\\tc\\bgi"); cout<<"\t\tHello friends!! This is Polygon Clipping\n\n "; cout<<"\t\t\t\t***WINDOW***\n"; cout<<"\n\n\t\t (200,100)"; rectangle(200,100,400,250); cout<<"\n\n\n\n\n\n\n\n\n\n\n\t\t\t\t\t\t(400,250)"; cout<<"\n\n\n"; cout<<"\nEnter the number of vertices of polygon : "; int n=0; cin>>n; int i; cout<<"Enter the polygon in clockwise direction"; int x1,y1,x2,y2; for(i=0;i<n;++i) { cout<<"\nEnter the end points of edge (x1,y1) (x2,y2) "; cin>>x1>>y1; cin>>x2>>y2; if(x2==x1) m[i]=9999; else m[i]=( (0.1*(y2-y1)) / (0.1*(x2-x1)) ); px[i]=x1; py[i]=y1; } for(i=0;i<n;++i) { line(px[i],py[i],px[(i+1)%n],py[(i+1)%n]); } delay(3000); cleardevice(); cout<<"\n\t\tLeft clipping"; /*for(i=0;i<n;++i) if(px[i]<200) l=i;*/ int l=-1; for(i=0;i<n;++i) { ++l; float y; if(px[i]<200 && px[(i+1)%n]>200) { y=gety(200,m[i],i); lx[l]=200; ly[l]=y; lx[l+1]= px[(i+1)%n]; ly[l+1]= py[(i+1)%n]; ++l; } else if(px[i]<200 && px[(i+1)%n]<200) --l; else if(px[i]>200 && px[(i+1)%n]>200) { lx[l]=px[(i+1)%n]; ly[l]=py[(i+1)%n]; } else if(px[i]>200 && px[(i+1)%n]<200) { y=gety(200,m[i],i); lx[l]=200; ly[l]=y; } } /* for(i=0;i<=l;++i) cout<<" "<<lx[i]; for(i=0;i<=l;++i) cout<<" "<<ly[i]; */ setcolor(WHITE); rectangle(200,100,400,250); setcolor(RED); ++l; for(i=0;i<l-1;++i) { line(lx[i],ly[i],lx[(i+1)],ly[(i+1)]); } line(lx[l-1],ly[l-1],lx[0],ly[0]); ++c; /* cout<<"Value of l = "<<l; for(i=0;i<n;++i) cout<<"m= "<<m[i]; */ delay(6000); cleardevice(); cout<<"\n\t\t Right clip"; for(i=0;i<l;++i) { if(lx[(i+1)%l]==lx[i]) m[i]=999; else m[i]=((0.1*(ly[(i+1)%l]-ly[i]))/(0.1*(lx[(i+1)%l]-lx[i]))); } int r=-1; for(i=0;i<l;++i) { ++r; float y; if(lx[i]>400 && lx[(i+1)%l]<400) { y=gety(400,m[i],i); rx[r]=400; ry[r]=y; rx[r+1]= lx[(i+1)%l]; ry[r+1]= ly[(i+1)%l]; ++r; } else if(lx[i]>400 && lx[(i+1)%l]>400) --r; else if(lx[i]<400 && lx[(i+1)%l]<400) { rx[r]=lx[(i+1)%l]; ry[r]=ly[(i+1)%l]; } else if(lx[i]<400 && lx[(i+1)%l]>400) { y=gety(400,m[i],i); rx[r]=400; ry[r]=y; } //'''''./////////////////// } ++r; /* for(i=0;i<r;++i) cout<<" "<<rx[i]; for(i=0;i<r;++i) cout<<" "<<ry[i]; */ setcolor(WHITE); rectangle(200,100,400,250); setcolor(GREEN); for(i=0;i<r;++i) { line(rx[i],ry[i],rx[(i+1)%r],ry[(i+1)%r]); } ++c; // cout<<"Value of r = "<<r; delay(3000); cleardevice(); cout<<"\n\t\t Bottom clip"; for(i=0;i<r;++i) { if(rx[(i+1)%r]==rx[i]) m[i]=999; else m[i]=((0.1*(ry[(i+1)%r]-ry[i]))/(0.1*(rx[(i+1)%r]-rx[i]))); } int b=-1; for(i=0;i<r;++i) { ++b; float x; if(ry[i]>250 && ry[(i+1)%r]<250) { x=getx(250,m[i],i); //////////////////////////// by[b]=250; bx[b]=x; bx[b+1]= rx[(i+1)%r]; by[b+1]= ry[(i+1)%r]; ++b; } else if(ry[i]>250 && ry[(i+1)%r]>250) --b; else if(ry[i]<250 && ry[(i+1)%r]<250) { bx[b]=rx[(i+1)%r]; by[b]=ry[(i+1)%r]; } else if(ry[i]<250 && ry[(i+1)%r]>250) { x=getx(250,m[i],i); by[b]=250; bx[b]=x; } } ++b; /* for(i=0;i<b;++i) cout<<" "<<bx[i]; for(i=0;i<b;++i) cout<<" "<<by[i]; */ setcolor(WHITE); rectangle(200,100,400,250); setcolor(YELLOW); for(i=0;i<b;++i) { line(bx[i],by[i],bx[(i+1)%b],by[(i+1)%b]); } ++c; // cout<<"Value of b = "<<b ; delay(3000); cleardevice(); cout<<"\n\t\tTop clip"; cout<<"\n\t The final CLIPPED POLYGON is as shown above"; for(i=0;i<b;++i) { if(bx[(i+1)%b]==bx[i]) m[i]=999; else m[i]=((0.1*(by[(i+1)%b]-by[i]))/(0.1*(bx[(i+1)%b]-bx[i]))); } int t=-1; for(i=0;i<b;++i) { ++t; float x; if(by[i]<100 && by[(i+1)%b]>100) { x=getx(100,m[i],i); //////////////////////////// ty[t]=100; tx[t]=x; tx[t+1]=bx[(i+1)%b]; ty[t+1]=by[(i+1)%b]; ++t; } else if(by[i]<100 && by[(i+1)%b]<100) --t; else if(by[i]>100 && by[(i+1)%b]>100) { tx[t]=bx[(i+1)%b]; ty[t]=by[(i+1)%b]; } else if(by[i]>100 && by[(i+1)%b]<100) { x=getx(100,m[i],i); ty[t]=100; tx[t]=x; } } ++t; /* for(i=0;i<t;++i) cout<<" "<<tx[i]; for(i=0;i<t;++i) cout<<" "<<ty[i]; */ setcolor(WHITE); rectangle(200,100,400,250); setcolor(BLUE); for(i=0;i<t;++i) { line(tx[i],ty[i],tx[(i+1)%t],ty[(i+1)%t]); } ++c; // cout<<"Value of t = "<<t ; getch(); closegraph(); } int gety(int x,float m,int i) { if(c==0) return (py[i]+(m*(x-px[i]))); if(c==1) return (ly[i]+(m*(x-lx[i]))); if(c==2) return (ry[i]+(m*(x-rx[i]))); if(c==3) return (by[i]+(m*(x-bx[i]))); } int getx(int y,float m ,int i) { if(c==0) return (px[i]+((y-py[i])/m)); if(c==1) return (lx[i]+((y-ly[i])/m)); if(c==2) return (rx[i]+((y-ry[i])/m)); if(c==3) return (bx[i]+((y-by[i])/m)); }