# include <iostream.h> # include <graphics.h> # include <conio.h> # include <math.h> void show_screen( ); void Bezier_curve(const int,const int *); double nCr(int,int); double factorial(int); void Dashed_line(const int,const int,const int,const int,const int=0); int main( ) { int driver=VGA; int mode=VGAHI; int n; do { show_screen( ); gotoxy(8,10); cout<<\"Degree of Bezier Curve : n :\"; gotoxy(8,11); cout<<\"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ\"; gotoxy(12,13); cout<<\"Enter the value of n (n>=2) = \"; cin>>n; int *control_points=new int[((n*2)+2)]; for(int count=0;count<=n;count++) { gotoxy(8,18); cout<<\"Coordinates of Point-\"<<count<<\" (x\"<<count<<\",y\"<<count<<\") :\"; gotoxy(8,19); cout<<\"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ\"; gotoxy(12,21); cout<<\"Enter the value of x\"<<count<<\" = \"; cin>>control_points[(count*2)]; gotoxy(12,22); cout<<\"Enter the value of y\"<<count<<\" = \"; cin>>control_points[((count*2)+1)]; gotoxy(8,18); cout<<\" \"; gotoxy(12,21); cout<<\" \"; gotoxy(12,22); cout<<\" \"; } initgraph(&driver,&mode,\"..\\\\Bgi\"); setcolor(15); Bezier_curve(n,control_points); delete control_points; setcolor(15); outtextxy(110,460,\"Press <Enter> to continue or any other key to exit.\"); int key=int(getch( )); if(key!=13) break; } while(1); return 0; } //-------------------------- Bezier_curve( ) --------------------------// void Bezier_curve(const int n,const int *cp) { int color=getcolor( ); setcolor(7); for(int count=0;count<n;count++) Dashed_line(cp[(count*2)],cp[((count*2)+1)], cp[((count+1)*2)],cp[(((count+1)*2)+1)]); double x; double y; for(float u=0.0005;u<=1;u+=0.0005) { x=0; y=0; for(int k=0;k<=n;k++) { x+=(cp[(k*2)]*nCr(n,k)*pow(u,k)*powl((1-u),(n-k))); y+=(cp[((k*2)+1)]*nCr(n,k)*pow(u,k)*powl((1-u),(n-k))); } putpixel((int)(x+0.5),(int)(y+0.5),color); } } //------------------------------ nCr( ) -------------------------------// double nCr(int n,int r) { double nf; double rf; double nrf; double ncr; nf=factorial(n); rf=factorial(r); nrf=factorial((n-r)); ncr=(nf/(rf*nrf)); return ncr; } //--------------------------- factorial( ) ----------------------------// double factorial(int number) { double factorial=1; if(number==0 || number==1); else { for(int count=1;count<=number;count++) factorial=factorial*count; } return factorial; } //--------------------------- Dashed_line( ) --------------------------// void Dashed_line(const int x_1,const int y_1,const int x_2, const int y_2,const int line_type) { int count=0; int color=getcolor( ); int x1=x_1; int y1=y_1; int x2=x_2; int y2=y_2; if(x_1>x_2) { x1=x_2; y1=y_2; x2=x_1; y2=y_1; } int dx=abs(x2-x1); int dy=abs(y2-y1); int inc_dec=((y2>=y1)?1:-1); if(dx>dy) { int two_dy=(2*dy); int two_dy_dx=(2*(dy-dx)); int p=((2*dy)-dx); int x=x1; int y=y1; putpixel(x,y,color); while(x<x2) { x++; if(p<0) p+=two_dy; else { y+=inc_dec; p+=two_dy_dx; } if((count%2)!=0 && line_type==0) putpixel(x,y,color); else if((count%5)!=4 && line_type==1) putpixel(x,y,color); else if((count%10)!=8 && (count%10)!=9 && line_type==2) putpixel(x,y,color); else if((count%20)!=18 && (count%20)!=19 && line_type==3) putpixel(x,y,color); else if((count%12)!=7 && (count%12)!=8 && (count%12)!=10 && (count%12)!=11 && line_type==4) putpixel(x,y,color); count++; } } else { int two_dx=(2*dx); int two_dx_dy=(2*(dx-dy)); int p=((2*dx)-dy); int x=x1; int y=y1; putpixel(x,y,color); while(y!=y2) { y+=inc_dec; if(p<0) p+=two_dx; else { x++; p+=two_dx_dy; } if((count%2)!=0 && line_type==0) putpixel(x,y,color); else if((count%5)!=4 && line_type==1) putpixel(x,y,color); else if((count%10)!=8 && (count%10)!=9 && line_type==2) putpixel(x,y,color); else if((count%20)!=18 && (count%20)!=19 && line_type==3) putpixel(x,y,color); else if((count%12)!=7 && (count%12)!=8 && (count%12)!=10 && (count%12)!=11 && line_type==4) putpixel(x,y,color); count++; } } } //-------------------------- show_screen( ) ---------------------------// void show_screen( ) { restorecrtmode( ); clrscr( ); textmode(C4350); cprintf(\"\\n********************************************************************************\"); cprintf(\"*-*****************************- -*****************************-*\"); cprintf(\"*------------------------------- \"); textbackground(1); cprintf(\" Bezier Curve \"); textbackground(8); cprintf(\" -------------------------------*\"); cprintf(\"*-*****************************- -*****************************-*\"); cprintf(\"*-****************************************************************************-*\"); for(int count=0;count<42;count++) cprintf(\"*-* *-*\"); gotoxy(1,46); cprintf(\"*-****************************************************************************-*\"); cprintf(\"*------------------------------------------------------------------------------*\"); cprintf(\"********************************************************************************\"); gotoxy(1,2); }