1. Vẽ Elip

/*------------------------------

FILE : ELIP.CPP

AUTHOR: Mr.Hai

UPDATE: 03/03/2010

------------------------------*/

#include<stdio.h>

#include<conio.h>

#include<graphics.h>

#include<dos.h>

// Ham khoi tao che do do hoa

void InitGraph()

{

int gd=0, gm=0;

initgraph(&gd,&gm,"d:\\tc\\bgi");

//setbkcolor(RED);

//setcolor(YELLOW);

}

// Ham ve 4 diem anh

void Put4Pixel(int a,int b,int x,int y,int c)

{

putpixel(a+x,b+y,c);

putpixel(a+x,b-y,c);

putpixel(a-x,b+y,c);

putpixel(a-x,b-y,c);

}

// Ham ve duong elip tam I(x0,y0), ban kinh 1 bang a, ban kinh 2 bang b

void DrawElip(int x0,int y0, int a, int b, int c)

{

double a1,b1,d1,d2;

int x=0;

int y=b;

a1=a*a;

b1=b*b;

d1=b1-a1*b+a1/4;

d2=b1*(x+1/2)*(x+1/2)+a1*(y-1)*(y-1)-a1*b1;

//kiem tra gradient F van nam trong mien 1

while(2*b1*(x+1)<a1*(2*y-1))

{

// trong mien 1

Put4Pixel(x0,y0,x,y,c);

if(d1<0) //chon S

d1=d1+b1*(2*x+3);

else //chon P

{

d1=d1+b1*(2*x+3)+a1*(2-2*y);

y--;

}

x++;

delay(20);

}

while(y>=0)

{

// trong mien 2

Put4Pixel(x0,y0,x,y,c);

if(d2>=0) //chon L

d2=d2+a1*(3-2*y);

else //chon R

{

d2=d2+a1*(3-2*y)+b1*(2*x+2);

x++;

}

y--;

delay(20);

}

}

void main()

{

int x0,y0,a,b;

printf("

Nhap toa do tam elip I(x0,y0) = "); scanf("%d%d",&x0,&y0);

printf("

Nhap ban kinh a = ");scanf("%d",&a);

printf("

Nhap ban kinh b = ");scanf("%d",&b);

InitGraph();

DrawElip(x0,y0,a,b,WHITE);

getch();

closegraph();

}

2.Vẽ Đoạn Thẳng

/*------------------------------

FILE : LINE.CPP

AUTHOR: Mr.Hai

UPDATE: 18/03/2010

------------------------------*/

#include <stdio.h>

#include <conio.h>

#include <graphics.h>

#include <dos.h>

// Ham khoi tao che do do hoa

void InitGraph()

{

int gd=0, gm=0;

initgraph(&gd,&gm,"d:\\tc\\bgi");

//setbkcolor(RED);

//setcolor(YELLOW);

}

// Ham ve doan thang tu A(xa,ya) den B(xb,yb) voi he so goc la m

void DrawLine(int xa,int ya,int xb,int yb,int c)

{

int x,y,Dx,Dy,d,c1,c2,tg;

x = xa;

y = ya;

if(xa>xb) // dam bao Dx luon duong

{

tg=xa; xa=xb; xb=tg;

tg=ya; ya=yb; yb=tg;

}

Dx = xb - xa;

Dy = yb - ya;

d = 2*Dy - Dx;

c1 = 2*Dy ;

c2 = 2*(Dy - Dx);

// TH: m=0

if(Dy == 0)

for(x=xa;x<=xb;x++)

{

putpixel(x,ya,c);

delay(20);

}

// TH: m=1

if(Dy == Dx)

for(x=xa,y=ya;x<=-xb;x++,y++)

{

putpixel(x,y,c);

delay(20);

}

// TH: m=-1

if(Dy == -Dx)

for(x=xa,y=ya;x<=xb;x++,y--)

{

putpixel(xa,ya,c);

delay(20);

}

// TH: m=vo cung

if(Dx == 0)

{

int y1=ya<yb ? ya:yb;

int y2=ya>yb ? ya:yb;

for(y=y1;y<=y2;y++)

{

putpixel(xa,y,c);

delay(20);

}

}

// TH: 0<m<1

if((Dx>0) && (Dy<Dx))

{

for(x=xa;x<=xb;x++)

{

putpixel(x,y,c);

if(d<0)

d+=c1;

else

{

y++;

d+=c2;

}

delay(20);

}

}

// TH: m>1

if(Dy>Dx)

{

int x1a=ya; int y1a=xa;

int x1b=yb; int y1b=xb;

int D1x=Dy; int D1y=Dx;

y=y1a;

d=2*D1y-D1x;

c1=2*D1y;

c2=2*(D1y-D1x);

for(x=x1a;x<=x1b;x++)

{

putpixel(y,x,c);

if(d<0)

d+=c1;

else

{

y++;

d+=c2;

}

delay(20);

}

}

// TH: -1<m<0

if((-Dx<Dy)&&(Dy<0))

{

int x1a=-xb; int y1a=yb;

int x1b=-xa; int y1b=ya;

int D1x=Dx; int D1y=-Dy;

y=y1a;

d=2*D1y-D1x;

c1=2*D1y;

c2=2*(D1y-D1x);

for(x=x1a;x<=x1b;x++)

{

putpixel(-x,y,c);

if(d<0)

d+=c1;

else

{

y++;

d+=c2;

}

delay(20);

}

}

// TH: m<-1

if(Dy<-Dx)

{

xa=-yb; ya=-xb;

xb=ya ; yb=-xa;

int D1x=-Dy; int D1y=Dx;

d=2*D1y-D1x;

c1=2*D1y;

c2=2*(D1y-D1x);

for(x=xa;x<=xb;x++)

{

putpixel(-y,x,c);

if(d<0)

d+=c1;

else

{

y++;

d+=c2;

}

delay(20);

}

}

}

void main()

{

int xa,ya,xb,yb;

printf("Nhap tao do diem thu nhat: A(xa,ya) = "); scanf("%d%d",&xa,&ya);

printf("Nhap tao do diem thu hai : B(xb,yb) = "); scanf("%d%d",&xb,&yb);

InitGraph();

DrawLine(xa,ya,xb,yb,WHITE);

getch();

closegraph();

}

3.Vẽ Đường Tròn

/*------------------------------

FILE: CIRCLE.CPP

AUTHOR: Mr.Hai

UPDATE: 02/03/2010

------------------------------*/

#include <stdio.h>

#include <conio.h>

#include <graphics.h>

#include <dos.h>

void InitGraph()

{

int gd=0,gm=0;

initgraph(&gd,&gm,"d:\\tc\\bgi");

//setbkcolor(RED);

//setcolor(WHITE);

}

void DrawCircle(int x,int y,int r,int c)

{

int a,b,d;

a = 0;

b = r;

d = 1-r;

while(a<=b)

{

putpixel( a+x, b+y,c);

putpixel( a+x,-b+y,c);

putpixel(-a+x, b+y,c);

putpixel(-a+x,-b+y,c);

putpixel( b+x, a+y,c);

putpixel( b+x,-a+y,c);

putpixel(-b+x, a+y,c);

putpixel(-b+x,-a+y,c);

if(d<0)

{

d+= 2*a+3;

}

else

{

d+= 2*a - 2*b + 5;

b--;

}

a++;

delay(20); // xem qua trinh ve duong tron

}

}

void main()

{

int m,n,p;

printf("Nhap toa do tam duong tron: I(m,n) = "); scanf("%d%d",&m,&n);

printf("Nhap ban kinh: r = "); scanf("%d",&p);

InitGraph();

DrawCircle(m,n,p,WHITE);

getch();

closegraph();

}

void dda(int x1,int y1,int x2,int y2,int color=YELLOW)

{

float x=x1,y=y1,temp=(abs(x2-x1)>=abs(y2-y1))?abs(x2-x1):abs(y2-y1);

putpixel(int(x+.05),int(y+0.5),color);

for(int i=0;i<temp;i++)

{

x+=(x2-x1)/temp;

y+=(y2-y1)/temp;

putpixel(int(x+.05),int(y+0.5),color);

}

}

nài thì hình tròn

PHP Code:

void put8pixel(int x,int y,int xc,int yc,int c)

{

putpixel( x+xc , y+yc, c);

putpixel(-x+xc , y+yc, c);

putpixel( x+xc ,-y+yc, c);

putpixel(-x+xc ,-y+yc, c);

putpixel( y+xc , x+yc, c);

putpixel(-y+xc , x+yc, c);

putpixel( y+xc ,-x+yc, c);

putpixel(-y+xc ,-x+yc, c);

}

void hinhtron(int xc,int yc,int r,int c=8)

{

int x=0,y=r,p=3-2*r;

put8pixel(x,y,xc,yc,c);

while (x<=y)

{

if(p<0)p+=4*x+++6;

else p+= 4*(x++-y--)+10;

put8pixel(x,y,xc,yc,c);

}

}

nài thì hình chữ nhật

PHP Code:

void hcn(int x1,int y1,int x2,int y2,int color)// hinh chu nhat thiet lap 1 hinh chu nhat nhu ham window

{

for(int i=y1;i<=y2;i++)

for(int j=x1;j<=x2;j++)

putpixel(j,i,color);