Comuter graphics 2D transformation

#include " stdio.h "
#include " conio.h "
#include " math.h "
#include " graphics.h "
#include " stdlib.h "
#include " ctype.h "

void intgraph();
void display_cordinate(char bg_color,char line_color);
int Create_poly(int poly[][2]);
void fill_poly(int poly[][2],int points,char line_color,char fill_color);
void Identity(float Matrix[3][3]);
void Translate_to_Relative(int poly[][2],int points,int Xdis,int Ydis);

int instance=0;
int current=-1;


void main()
{
    int poly[10][10][2],i,points[10],Xdis[10],Ydis[10];
    float Sx,Sy,Matrix[10][3][3],temp,Cos,Sin;
    char ch;
    intgraph();

    setfillstyle(8,RED);
    points[current]=Create_poly(poly[current+1]);
    display_cordinate(DARKGRAY,WHITE);
    fill_poly(poly[current],points[current],BLUE,YELLOW);

    Identity(Matrix[current]);
    getch();
    Xdis[current]=0-poly[current][0][0];
    Ydis[current]=0-poly[current][0][1];

    Translate_to_Relative(poly[current],points[current],Xdis[current],Ydis[current]);

   Menu:
      restorecrtmode();
      do
      {
  clrscr();
   instance=0;
       printf("\t\t0. Instance transformation\n");
       printf("\t\t1. Scaling\n");
       printf("\t\t2. Translation\n");
       printf("\t\t3. Rotation\n");
       printf("\t\t4. Reflection [ X axis ]\n");
       printf("\t\t5. Reflection [ Y axis ]\n");
       printf("\t\t6. Reflection [ X=Y axis ]\n");
       printf("\t\t7. Draw \n");
       printf("\t\t8. New input set\n");
       printf("\t\t9. EXIT \n");


  printf("\n\nChoice: ");
  ch=getche();
      }while((ch < '0')||(ch > '9'));

      switch(ch)
      {
  case '0':
    //printf("Available instances are:");
    instance=1;
    goto babu;
  case '1':
     printf("\n\tScaling Ratio: ");
     printf("\n\tSx: ");
     scanf("%f",&Sx);
     printf("\n\tSy: ");
     scanf("%f",&Sy);
     for(i=0;i<3;i++)
     {
        Matrix[current][i][0]=Matrix[current][i][0]*Sx;
        Matrix[current][i][1]=Matrix[current][i][1]*Sy;
     }
     goto Menu;

  case '2':
     printf("\n\tTranslation : ");
     printf("\n\tTx: ");
     scanf("%f",&Sx);
     printf("\n\tTy: ");
     scanf("%f",&Sy);

     Matrix[current][2][0]=Matrix[current][2][0]+Sx;
     Matrix[current][2][1]=Matrix[current][2][1]+Sy;

     goto Menu;

  case '3':
     printf("\nRotation Angle [in Degree]: ");
     scanf("%f",&Sx);

     Sx=(Sx*3.14159265358)/180.0;
     Cos=cos(Sx);
     Sin=sin(Sx);
     for(i=0;i<=2;i++)
     {
        temp=Matrix[current][i][0]*Cos-Matrix[current][i][1]*Sin;
        Matrix[current][i][1]=Matrix[current][i][0]*Sin+Matrix[current][i][1]*Cos;
        Matrix[current][i][0]=temp;
     }
     goto Menu;

  case '4':
     Matrix[current][1][1]=Matrix[current][1][1]*-1;
     printf("\t\tCompleted");
     getch();

     goto Menu;

  case '5':
     Matrix[current][0][0]=Matrix[current][0][0]*-1;
     printf("\t\tCompleted");
     getch();

     goto Menu;

  case '6':
     Matrix[current][0][1]=1;
     Matrix[current][1][1]=1;
     printf("\t\tCompleted");
     getch();
     goto Menu;

  case '7':
        if(!instance)
        {int j =current;
        for(i=0;i<=points[j];i++)
      {
         temp=poly[j][i][0]*Matrix[j][0][0]+poly[j][i][1]*Matrix[j][1][0]+Matrix[j][2][0];
         poly[j][i][1]=poly[j][i][0]*Matrix[j][0][1]+poly[j][i][1]*Matrix[j][1][1]+Matrix[j][2][1];
         poly[j][i][0]=temp;
      }

       }

     goto babu;

  case '8':
  points[current]=Create_poly(poly[current+1]);
  Identity(Matrix[current]);
  Xdis[current]=0-poly[current][0][0];
  Ydis[current]=0-poly[current][0][1];
  Translate_to_Relative(poly[current],points[current],Xdis[current],Ydis[current]);
  goto Menu;

  case '9':
     getch();
     exit(0);

      }
      babu:
      setgraphmode(2);
      display_cordinate(DARKGRAY,WHITE);

      if(instance)
      {
  for(int u=0;u<=current;u++)
  {
    Translate_to_Relative(poly[u],points[u],-Xdis[u],-Ydis[u]);
     fill_poly(poly[u],points[u],BLUE,YELLOW);
     //getch();
     //printf("1");
  }
  instance=0;
      }
      else
      {       Translate_to_Relative(poly[current],points[current],-Xdis[current],-Ydis[current]);
       fill_poly(poly[current],points[current],BLUE,YELLOW);
      }
      getch();
      restorecrtmode();
      do
      {
  clrscr();
  printf("\n\tDo you Want to Switch to MENU [Y|N]:- ");
  ch=toupper(getche());
      }while( (ch!='Y') && (ch!='N') );
      if(ch=='Y')
      {
  //Identity(Matrix[current]);
  Xdis[current]=0-poly[current][0][0];
  Ydis[current]=0-poly[current][0][1];

  Translate_to_Relative(poly[current],points[current],Xdis[current],Ydis[current]);
  goto Menu;
      }
      closegraph();
   }

   void intgraph()
   {
      int g=DETECT,d;
      initgraph(&g,&d,"e:\\tc\\bgi");
   }

   void fill_poly(int poly1[][2],int points,char line_color,char fill_color)
   {
      int pol[20],i;
      char str[2];
      int fac=5;
      for(i=0;i<=points;i++)
      {
  pol[i*2]=320+fac*poly1[i][0];
  pol[i*2+1]=240-fac*poly1[i][1];
      }
      pol[i*2]=320+fac*poly1[0][0];
      pol[i*2+1]=240-fac*poly1[0][1];

      setcolor(line_color);
      if(points>2)
      setfillstyle(1,fill_color);
      fillpoly(points,pol);


   }

   void Identity(float Matrix[3][3])
   {
      int i,j;
      for(i=0;i<=2;i++)
      {
  for(j=0;j<=2;j++)
  {
     if(i==j)
        Matrix[i][j]=1;
     else
        Matrix[i][j]=0;
  }
      }
   }
   int Create_poly(int poly[][2])
   {
      //printf("%d %d\n\n",getmaxx(),getmaxy());//640 480
      current++;
      int total_point;
      printf("No of vertices: ");
      scanf("%d",&total_point);

      for(int i=0;i < total_point;i++)
      {
 printf("Co-ordinate [%d]: ",i+1);
 scanf("%d %d",&poly[i][0],&poly[i][1]);

      }

      return total_point;
   }

   void display_cordinate(char bg_color,char line_color)
   {
      int i;
      setbkcolor(bg_color);
      setcolor(line_color);
      for(i=0;i<=640;i+=5)
      {
  line(i,0,i,480);
      }

      for(i=0;i<=480;i+=5)
      {
  line(0,i,640,i);
      }

      rectangle(0,0,639,479);

      setcolor(RED);
      line(0,240,640,240);
      line(320,0 ,320,480);
   }

   void Translate_to_Relative(int poly[][2],int points,int Xdis,int Ydis)
   {
      int i;
      for(i=0;i<=points;i++)
      {
  poly[i][0]=poly[i][0]+Xdis;
  poly[i][1]=poly[i][1]-Ydis;
      }
   }