Question

Write a Program To apply Basic 2D Transformation(Translation , rotation , Scaling

Answer 1

#include<graphics.h>
#include<conio.h>
#include<math.h>
#include<stdio.h>

   int main()
   {
   int i, x, y, tx, ty, sx, sy, angle=10, xmax, ymax, xmid, ymid, op;
   int gd,gm;
   float p1[10]=  {	50,50,
			100,50,
			100,100,
			50,100,
			50,50,
		   };
   int pi[10];
   float b[3][3]={	1,0,0,
			0,1,0,
			0,0,1
		};
   int c[1][1];
   float a[1][1];
	  printf("\nSelect the transformation : ");
	  printf("\n1 : Traslation");
	  printf("\n2 : Rotation");
	  printf("\n3 : Scaling");
	  printf("\n4 : Rotation about arbitrary point");
	  printf( "\nEnter the option : ");
	  scanf("%d",&op);
	  switch(op)
	  {
		case 1: printf("\nEnter x traslation : ");
				scanf("%d",&tx);
				printf("\nEnter y traslation : ");
				scanf("%d",&ty);

		b[0][0] = 1;
		b[0][1] = 0;
		b[0][2] = 0;

		b[1][0] = 0;
		b[1][1] = 1;
		b[1][2] = 0;

		b[2][0] = tx;
		b[2][1] = ty;
		b[2][2] = 1;

		break;
	case 2: 	printf("\nEnter Rotation angle : ");
				scanf("%d",&angle);
		b[0][0] =cos(angle*3.142/180);
		b[0][1] =sin(angle*3.142/180);
		b[0][2] = 0;

		b[1][0] =-sin(angle*3.142/180);
		b[1][1] = cos(angle*3.142/180);
		b[1][2] = 0;

		b[2][0] = 0;
		b[2][1] = 0;
		b[2][2] = 1;

		break;
	case 3: 	printf("\nEnter x scaling : ");
		scanf("%d",&sx);
		printf("\nEnter y scaling : ");
		scanf("%d",&sy);

		b[0][0] = sx;
		b[0][1] = 0;
		b[0][2] = 0;

		b[1][0] = 0;
		b[1][1] = sy;
		b[1][2] = 0;

		b[2][0] = 0;
		b[2][1] = 0;
		b[2][2] = 1;

		break;
	case 4: 	printf("\nEnter x coordinate of arbitrary point : ");
		scanf("%d",&x);
		printf("\nEnter y coordinate of arbitrary point : ");
		scanf("%d",&y);
		printf("\nEnter Rotation angle : ");
		scanf("%d",&angle);

		tx = x;
		ty = y;

		b[0][0] =cos(angle*3.142/180);
		b[0][1] =sin(angle*3.142/180);
		b[0][2] = 0;

		b[1][0] =-sin(angle*3.142/180);
		b[1][1] = cos(angle*3.142/180);
		b[1][2] = 0;

		b[2][0] = -tx* cos(angle*3.142/180) + ty*sin(angle*3.142/180)+tx;
		b[2][1] = -tx* sin(angle*3.142/180) - ty*cos(angle*3.142/180)+ty;
		b[2][2] = 1;

	  }
		detectgraph(&gd,&gm);
		initgraph(&gd,&gm,"\\tc\\bgi");	// Initialize graphics
	xmax = getmaxx();		// Get maximum x coordinate
	ymax = getmaxy();		// Get maximum y coordinate
	xmid = xmax/2;		// Get the center x coordinate
	ymid = ymax/2;		// Get the center y coordinate

	setcolor(1);
	line(xmid,0,xmid,ymax);	// Draw y coordinate
	line(0, ymid, xmax, ymid);	// Draw x coordinate

	  setcolor(4);
	  for (i=0; i<8;i=i+2)
	  {
	  line(p1[i]+xmid,ymid-p1[i+1],xmid+p1[i+2],ymid-p1[i+3]);
	  }
	  for(i=0;i<9;i=i+2)
	  { 	a[0][0]=p1[i];
		a[0][1]=p1[i+1];
		c[0][0] = a[0][0]*b[0][0]+a[0][1]*b[1][0]+b[2][0];
		c[0][1] = a[0][0]*b[0][1]+a[0][1]*b[1][1]+b[2][1];
		pi[i]=c[0][0];
		pi[i+1]=c[0][1];
	  }
  setcolor(15);
	  for (i=0; i<8;i=i+2)
	  {
	  line(xmid+pi[i],ymid-pi[i+1],xmid+pi[i+2],ymid-pi[i+3]);
	  }
	  getch();
	  closegraph();
	  return 0;
   }