2D Transformations > C Program

Computer Graphics

2D Transformations > C Program

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
#include<math.h>
int x1,x2,x3,y1,y2,y3,x11,x22,x33,y11,y22,y33,xc,yc,xmax,ymax;


void display()
{

 line(0,yc,xmax,yc);
 line(xc,0,xc,ymax);
 line(xc+x11,yc-y11,xc+x22,yc-y22);
 line(xc+x22,yc-y22,xc+x33,yc-y33);
 line(xc+x33,yc-y33,xc+x11,yc-y11);

}

void translate()
{

 int tx,ty;
 printf("Enter translation factor: tx,ty\n");
 scanf("%d%d",&tx,&ty);

 x11=x1+tx;
 y11=y1+ty;
 x22=x2+tx;
 y22=y2+ty;
 x33=x3+tx;
 y33=y3+ty;

 display();
}

void scale()
{

 float sx,sy;
 printf("Enter scaling factor:\n");
 scanf("%f%f",&sx,&sy);

 x11=x1*sx;
 x22=x2*sx;
 x33=x3*sx;
 y11=y1*sy;
 y22=y2*sy;
 y33=y3*sy;

 display();

}

void shearx()
{

int shx;
printf("Enter the shear factor:\n");
scanf("%d",&shx);

x11=x1+shx*y1;
x22=x2+shx*y2;
x33=x3+shx*y3;
y11=y1;
y22=y2;
y33=y3;

display();

}

void sheary()
{

int shy;
printf("Enter the shear factor:\n");
scanf("%d",&shy);

x11=x1
x22=x2;
x33=x3;
y11=y1+shy*x1;
y22=y2+shy*x2;
y33=y3+shy*x3;

display();

}


void rotate()
{

double theta;
printf("Enter the angle:\n");
scanf("%f",theta);

theta=theta*(3.14/180.0);
x11=x1*cos(theta)-y1*sin(theta);
y11=x1*sin(theta)+y1*cos(theta);
x22=x2*cos(theta)-y2*sin(theta);
y22=x2*sin(theta)+y2*cos(theta);
x33=x3*cos(theta)-y3*sin(theta);
y33=x3*sin(theta)+y3*cos(theta);

Display();

}

void refx()
{

y11=-y1;
y22=-y2;
y33=-y3;
x11=x1;
x22=x2;
x33=x3;

Display();

}

void refy()
{

x11=-x1;
x22=-x2;
x33=-x3;
y11=y1;
y22=y2;
y33=y3;

Display();

}

void refo()
{

x11=-x1;
x22=-x2;
x33=-x3;
y11=-y1;
y22=-y2;
y33=-y3;

Display();

}

void main()
{

 int gd=DETECT,gm,op,r;
 clrscr();
 printf("Enter co-ordinates for triangle:\n");
 scanf("%d%d%d%d%d%d",&x1,&y1,&x2,&y2,&x3,&y3);
 initgraph(&gd,&gm,"C:\\TurboC3\\BGI");

 xmax=getmaxx();
 ymax=getmaxy();
 xc=xmax/2;
 yc=ymax/2;

 do
{

 printf("Enter option:\n");
 printf("1. Translation\n 2. Scaling\n 3. Rotation\n 4.Reflection\n 5.Shear\n");
 scanf("%d",&op);
 line(0,yc,xmax,yc);
 line(xc,0,xc,ymax);
 line(xc+x1,yc-y1,xc+x2,yc-y2);
 line(xc+x2,yc-y2,xc+x3,yc-y3);
 line(xc+x3,yc-y3,xc+x1,yc-y1);
 switch(op)
 {
 case 1:translate();
break;
 case 2:scale();
break;
 case 3:rotate();
break;
 case 4:
 printf("\n1.About X \n 2.About Y \n 3.About Origin\nEnter your choice:\n");
 scanf("%d",&r);
 switch(r)
 {
 case 1:
 refx();
 break;
 case 2:
 refy();
 case 3:
 refo();
 break;
 }
 break;
 case 5:
 printf("\n1.About X\n2.About Y\nEnter your choice:\n");
 scanf("%d",&r);
 switch(r)
 {
 case 1:
 shearx();
 break;
 case 2:
 sheary();
 break;
 }
 break;
 default:printf("Invalid Option");
exit(0);
 }
 }
 while(op<=4);

 getch();

 }