Cg my own programs

1

/* Bresenham's Line drawing program */ #include<stdio.h>

#include<math.h>

#include<dos.h>

#include<conio.h>

#include<graphics.h>

void main()

{

int gdriver=DETECT,gmode,xs,ys,xe,ye,dx,dy,x,y,d,inc1,inc2,xend,yend;

float m;

clrscr();

initgraph(&gdriver,&gmode,"");

printf("enter line starting & ending end points");

scanf("%d%d%d%d",&xs,&ys,&xe,&ye);

dx=(xe-xs);

dy=(ye-ys);

if(dx==0)

{

x=xs;

if(dy<0)

{

y=ye;

yend=ys;

}

else

2

{

y=ys;

yend=ye;

}

while(y<=yend)

{

delay(10);

putpixel(x,y,GREEN);

if(d>=0)

{

d=d+inc2;

}

else

d=d+inc1;

y=y+1;

}

}

if(dx!=0)

{

m=(float) dy/dx;

if(m<=1)

{

inc1=2*abs(dy);

inc2=2*abs(dy-dx);

d=inc1-abs(dx);

3

if(dx<0)

{

x=xe;

y=ye;

xend=xs;

}

else

{

x=xs;

y=ys;

xend=xe;

}

while(x<=xend)

{ delay(10);

putpixel(x,y,GREEN);

if(d>=0)

{

y=y+1;

d=d+inc2;

}

else

d=d+inc1;

x=x+1;

}

}

4

else if(m>1)

{

inc1=2*dx;

inc2=2*(dx-dy);

d=inc1-dy;

if(dy<0)

{

x=xe;

y=ye;

xend=xs;

}

else

{

x=xs;

y=ys;

xend=xe;

}

while(x<=xend)

{

putpixel(x,y,RED);

if(d>=0)

{

x=x+1;

d=d+inc2;

}

5

else

d=d+inc1;

y=y+1;

}

}}

getch();

}

/* Simple DDA Line drawing program */#include<stdio.h>

#include<process.h>

#include<math.h>

#include<dos.h>

#include<conio.h>


float round(float r)

{

return(r+0.5);

}

void main()

{

int gdriver=DETECT,gmode,xs,ys,xe,ye,dx,dy,length,xend,yend;

float x,y,xinc,yinc;

clrscr();



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dx=xe-xs;

dy=ye-ys;

if(dx<0)

{

x=xe;

xend=xs;

}

else

{

x=xs;

xend=xe;

}

if(dy<0)

{

y=ye;

yend=ys;

}

else

{

y=ys;

yend=ye;

}

dx=abs(xe-xs);

dy=abs(ye-ys);

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printf("x=%f y=%f",x,y);

if(dy>dx)

length=dy;

else

length=dx;

if(dx==0 && dy==0)

{

putpixel(x,y,YELLOW);

getch();

exit(0);

}

xinc=(float)dx/length;

yinc=(float)dy/length;

if(dx==0)

{

while(y<=yend)

{

putpixel(floor(round(x)),floor(round(y)),RED);

x=x+xinc;

y=y+yinc;

}

}

else if(dx!=0)

{

while(x<=xend)

8

{

putpixel(floor(round(x)),floor(round(y)),BLUE);

x=x+xinc;

y=y+yinc;

}}

getch();

}

/* Symmetrical DDA Line drawing program */#include<stdio.h>

#include<process.h>

#include<math.h>

#include<dos.h>

#include<conio.h>


float round(float r)

{

return(r+0.5);

}

void main()

{

int gdriver=DETECT,gmode,xs,ys,xe,ye,dx,dy,length,xend,yend;

float x,y,xinc,yinc,n;

clrscr();



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dx=xe-xs;

dy=ye-ys;

if(dx<0)

{

x=xe;

xend=xs;

}

else

{

x=xs;

xend=xe;

}

if(dy<0)

{

y=ye;

yend=ys;

}

else

{

y=ys;

yend=ye;

}

dx=abs(xe-xs);

dy=abs(ye-ys);

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printf("x=%f y=%f",x,y);

if(dy>dx)

length=dy;

else

length=dx;

if(dx==0 && dy==0)

{

putpixel(x,y,YELLOW);

getch();

exit(0);

}

n=log(length)/log(2);

xinc=(float)dx/pow(2,ceil(n));

yinc=(float)dy/pow(2,ceil(n));

if(dx==0)

{

while(y<=yend)

{

putpixel(floor(round(x)),floor(round(y)),RED);

x=x+xinc;

y=y+yinc;

}

}

else if(dx!=0)

{

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while(x<=xend)

{

putpixel(floor(round(x)),floor(round(y)),BLUE);

x=x+xinc;

y=y+yinc;

}}

getch();

}

/* Circle drawing program using Trigonometric method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k;

float xend,x,y,temp,thetainc,theta,thetaend,angle;

clrscr();


printf("enter centre coordinates and radius of circle");

scanf("%d%d%d",&h,&k,&r);

temp=3.141/180;

thetainc=1.0/r;

theta=0;

thetaend=45;

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while(theta<=thetaend)

{

angle=temp*theta;

x=r*cos(angle);

y=r*sin(angle);

putpixel(x+h,y+k,RED);

putpixel(y+h,x+k,RED);

putpixel(-y+h,x+k,RED);

putpixel(-x+h,y+k,RED);

putpixel(-x+h,-y+k,RED);

putpixel(-y+h,-x+k,RED);

putpixel(y+h,-x+k,RED);

putpixel(x+h,-y+k,RED);

theta=theta+thetainc;

}

getch();

}

/* Circle drawing program using Polynomial method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k;

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float xend,x,y;

clrscr();




xend=r/1.414;

x=0;

y=r;

while(x<=xend)

{

y=sqrt(r*r-x*x);









x++;

}

getch();

}

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/* Circle drawing program using Bresenham's method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k,x,y,d;

clrscr();




x=0;

y=r;

d=3-2*r;

while(x<=y)

{









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if(d<0)

d=d+4*x+6;

else

{

d=d+4*(x-y)+10;

y--;

}

x++;

}

getch();

}

/* Circle drawing program using Mid-Point method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k,x,y,d;

clrscr();




x=0;

y=r;

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d=1-r;

while(x<=y)

{









if(d<0)

d=d+2*x+3;

else

{

d=d+2*(x-y)+5;

y--;

}

x++;

}

getch();

}

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/* Ellipse drawing program using Trigonometric method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k,a,b;

float xend,x,y,temp,thetainc,theta,thetaend,angle;

clrscr();


printf("enter centre coordinates of ellipse");

scanf("%d%d",&h,&k);

printf("enter major and minor axis of ellipse");

scanf("%d%d",&a,&b);

temp=3.141/180;

thetainc=3.141/(2*a);

theta=0;

thetaend=90;

while(theta<=thetaend)

{

angle=temp*theta;

x=a*cos(angle);

y=b*sin(angle);


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theta=theta+thetainc;

}

getch();

}

/* Ellipse drawing program using Polynomial method*/#include<stdio.h>

#include<math.h>

#include<conio.h>


void main()

{

int gdriver=DETECT,gmode,r,h,k,a,b;

float xend,x,y;

clrscr();


printf("enter centre coordinates of ellipse");

scanf("%d%d",&h,&k);

printf("enter major and minor axis of ellipse");

scanf("%d%d",&a,&b);

x=0;

xend=a;

while(x<=xend)

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{

y=b*sqrt(1-(x*x)/(a*a));





x++;

}

getch();

}

Laing Barsky line clipping algorithm


#include<dos.h>

#include<conio.h>

#include<stdlib.h>

void main()

{

int gd, gm ;

int x1 , y1 , x2 , y2 ;

int wxmin,wymin,wxmax, wymax ;

float u1 = 0.0,u2 = 1.0 ;

int p1 , q1 , p2 , q2 , p3 , q3 , p4 ,q4 ;

float r1 , r2 , r3 , r4 ;

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int x11 , y11 , x22 , y22 ;

clrscr();

printf("Enter the windows left xmin , top boundry ymin\n");

scanf("%d%d",&wxmin,&wymin);

printf("Enter the windows right xmax ,bottom boundry ymax\n");

scanf("%d%d",&wxmax,&wymax);

printf("Enter line x1 , y1 co-ordinate\n");

scanf("%d%d",&x1,&y1);

printf("Enter line x2 , y2 co-ordinate\n");

scanf("%d%d",&x2,&y2);

printf("liang barsky express these 4 inequalities using lpk<=qpk\n");

p1 = -(x2 - x1 ); q1 = x1 - wxmin ;

p2 = ( x2 - x1 ) ; q2 = wxmax - x1 ;

p3 = - ( y2 - y1 ) ; q3 = y1 - wymin ;

p4 = ( y2 - y1 ) ; q4 = wymax - y1 ;

printf("p1=0 line is parallel to left clipping\n");

printf("p2=0 line is parallel to right clipping\n");

printf("p3=0 line is parallel to bottom clipping\n");

printf("p4=0 line is parallel to top clipping\n");

if( ( ( p1 == 0.0 ) && ( q1 < 0.0 ) ) ||

( ( p2 == 0.0 ) && ( q2 < 0.0 ) ) ||

( ( p3 == 0.0 ) && ( q3 < 0.0 ) ) ||

( ( p4 == 0.0 ) && ( q4 < 0.0 ) ) )

{

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printf("Line is rejected\n");

getch();

detectgraph(&gd,&gm);

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

setcolor(RED);

rectangle(wxmin,wymax,wxmax,wymin);

setcolor(BLUE);

line(x1,y1,x2,y2);

getch();

setcolor(WHITE);

line(x1,y1,x2,y2);

getch();

}

else

{

if( p1 != 0.0 )

{

r1 =(float) q1 /p1 ;

if( p1 < 0 )

u1 = max(r1 , u1 );

else

u2 = min(r1 , u2 );

}

if( p2 != 0.0 )

{

22

r2 = (float ) q2 /p2 ;

if( p2 < 0 )

u1 = max(r2 , u1 );

else

u2 = min(r2 , u2 );

}

if( p3 != 0.0 )

{

r3 = (float )q3 /p3 ;

if( p3 < 0 )

u1 = max(r3 , u1 );

else

u2 = min(r3 , u2 );

}

if( p4 != 0.0 )

{

r4 = (float )q4 /p4 ;

if( p4 < 0 )

u1 = max(r4 , u1 );

else

u2 = min(r4 , u2 );

}

if( u1 > u2 )

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printf("line rejected\n");

else

{

x11 = x1 + u1 * ( x2 - x1 ) ;

y11 = y1 + u1 * ( y2 - y1 ) ;

x22 = x1 + u2 * ( x2 - x1 );

y22 = y1 + u2 * ( y2 - y1 );

printf("Original line cordinates\n");

printf("x1 = %d , y1 = %d, x2 = %d, y2 = %d\n",x1,y1,x2,y2);

printf("Windows coordinate are \n");

printf("wxmin = %d, wymin = %d,wxmax = %d , wymax = %d ",wxmin,wymin,wxmax,wymax);

printf("New coordinates are \n");

printf("x1 = %d, y1 = %d,x2 = %d , y2 = %d\n",x11,y11,x22,y22);

detectgraph(&gd,&gm);

initgraph(&gd,&gm,"C:\\TC\\BGI");

setcolor(2);

rectangle(wxmin,wymax,wxmax,wymin);

setcolor(1);

line(x1,y1,x2,y2);

getch();

setcolor(0);

line(x1,y1,x2,y2);

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setcolor(3);

line(x11,y11,x22,y22);

getch();

}

}

}

2d transformation#include<stdio.h>

#include<conio.h>

#include<math.h>


int x1,y1,x2,y2;

void translation()

{

int tx,ty,xn1,xn2,yn1,yn2;

printf("Enter the Translation Vector:");

scanf("%d\n%d",&tx,&ty);

cleardevice();

outtextxy(400,100,"TRANSLATION");

xn1=x1+tx;

yn1=y1+ty;

xn2=x2+tx;

yn2=y2+ty;

line(x1,y1,x2,y2);

line(xn1,yn1,xn2,yn2);

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getch();

}

void scaling()

{

int xn1,yn1,xn2,yn2;

float sx,sy;

printf("Enter the Sacling Factor:");

scanf("%f%f",&sx,&sy);

cleardevice();

outtextxy(300,200,"SCALING");

xn1=x1*sx;

yn1=y1*sy;

xn2=x2*sx;

yn2=y2*sy;

line(x1,y1,x2,y2);


getch();

}

void rotation()

{

int r;

float rx,xn1,yn1,xn2,yn2;

printf("Enter the Angle for Rotation:");

scanf("%d",&r);

cleardevice();

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outtextxy(500,200,"ROTATION");

rx=(r*3.14)/180;

xn1=x1*cos(rx)-y1*sin(rx);

yn1=y1*cos(rx)+x1*sin(rx);

xn2=x2*cos(rx)-y2*sin(rx);

yn2=y2*cos(rx)+x2*sin(rx);

line(x1,y1,x2,y2);


getch();

}

void shearing()

{

int sh;

float xn1,yn1,xn2,yn2;

printf("Enter the value of Shearing");

scanf("%d",&sh);

cleardevice();

outtextxy(500,100,"SHEARING");

xn1=x1+sh*y1;

yn1=y1;

xn2=x2+sh*y2;

yn2=y2;

line(x1,y1,x2,y2);


getch();

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}

void reflection()

{

int xn1,yn1,xn2,yn2;

cleardevice();

outtextxy(300,100,"REFLECTION");

if((x1<y1)||(x2<y2))

{

xn1=x1+50;

xn2=x2+50;

yn1=y1;

yn2=y2;

}

else

{

xn1=x1;

xn2=x2;

yn1=y1+50;

yn2=y2+50;

}

line(x1,y1,x2,y2);


getch();

}

void get()

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{

printf("Enter the Co-ordinates x1,y1,x2,y2:");

scanf("%d%d%d%d",&x1,&y1,&x2,&y2);

cleardevice();

outtextxy(200,100,"ORIGINAL OBJECT");

line(x1,y1,x2,y2);

getch();

}

void main()

{

int ch,gd=DETECT,gm;

initgraph(&gd,&gm,"C:/tc/bgi");

get();

do

{

cleardevice();

outtextxy(10,10,"1.Translation");

outtextxy(10,20,"2.Scaling");

outtextxy(10,30,"3.Rotation");

outtextxy(10,40,"4.Shearing");

outtextxy(10,50,"5.Reflection");

outtextxy(10,60,"6.Exit");

outtextxy(10,70,"Enter Your Choice:");

scanf("%d",&ch);

switch(ch)

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{

case 1:

{

translation();

break;

}

case 2:

{

scaling();

break;

}

case 3:

{

rotation();

break;

}

case 4:

{

shearing();

break;

}

case 5:

{

reflection();

break;

30

}

case 6:

{

exit(0);

break;

}

}

}

while(ch<6);

}

2d Viewing Transformation#include<stdio.h>

#include<conio.h>


void main()

{

int gm,gr,xwmin,ywmin,xwmax,

ywmax,xvmin,yvmin,xvmax,yvmax,xw,yw,xv,yv,sx,sy;

clrscr();

detectgraph(&gm,&gr);

initgraph(&gm,&gr,"d:\\tc\\BGI");

printf("Enter the window min coordinate(xwmin,ywmin):\n");

scanf("%d%d",&xwmin,&ywmin);

printf("Enter the window max coordinate(xwmax,ywmax):\n");

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scanf("%d%d",&xwmax,&ywmax);

printf("Enter the viewport min coordinate(xvmin,yvmin):\n");

scanf("%d%d",&xvmin,&yvmin);

printf("Enter the viewport max coordinate(xvmax,yvmax):\n");

scanf("%d%d",&xvmax,&yvmax);

sx=(xvmax-xvmin)/(xwmax-xwmin);

sy=(yvmax-yvmin)/(ywmax-ywmin);

printf("Enter the point coordinate(xw,yw) in the window:\n");

scanf("%d%d",&xw,&yw);

xv=(sx*(xw-xwmin))+xvmin;

yv=(sy*(yw-ywmin))+yvmin;

cleardevice();

getch();

rectangle(xwmin,ywmax,xwmax,ywmin);

putpixel(xw,yw,15); getch();

cleardevice();getch();

rectangle(xvmin,yvmax,xvmax,yvmin);

putpixel(xv,yv,15);

getch();

}

Cg my own programs

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Transcript of Cg my own programs