# include <iostream.h>
# include <graphics.h>
# include <conio.h>
# include <math.h>
void show_screen( );
void apply_reflection_about_line_yex(constint,int []);
void apply_reflection_about_line_yemx(constint,int []);
void apply_reflection_along_x_axis(constint,int []);
void apply_reflection_along_y_axis(constint,int []);
void apply_rotation(constint,int [],float);
void multiply_matrices(constfloat[3],constfloat[3][3],float[3]);
void Polygon(constint,constint []);
void Line(constint,constint,constint,constint);
void Dashed_line(constint,constint,constint,constint,constint=0);
int main( )
{
int driver=VGA;
int mode=VGAHI;
initgraph(&driver,&mode,"..\\Bgi");
show_screen( );
setcolor(15);
Line(320,100,320,400);
Line(315,105,320,100);
Line(320,100,325,105);
Line(315,395,320,400);
Line(320,400,325,395);
Line(150,240,500,240);
Line(150,240,155,235);
Line(150,240,155,245);
Line(500,240,495,235);
Line(500,240,495,245);
Dashed_line(160,400,460,100,0);
Dashed_line(180,100,480,400,0);
settextstyle(2,0,4);
outtextxy(305,85,"y-axis");
outtextxy(305,402,"y'-axis");
outtextxy(505,233,"x-axis");
outtextxy(105,233,"x'-axis");
outtextxy(350,100,"Reflection about the line y=x");
outtextxy(115,100,"Reflection about the line y=-x");
int x_polygon[8]={ 340,200, 420,120, 370,120, 340,200 };
int y_polygon[8]={ 300,200, 220,120, 270,120, 300,200 };
setcolor(15);
Polygon(4,x_polygon);
Polygon(4,y_polygon);
apply_reflection_about_line_yex(4,x_polygon);
apply_reflection_about_line_yemx(4,y_polygon);
setcolor(7);
Polygon(4,x_polygon);
Polygon(4,y_polygon);
getch( );
return 0;
}
/*************************************************************************///---------------- apply_reflection_about_line_yex( ) -----------------///*************************************************************************/void apply_reflection_about_line_yex(constint n,int coordinates[])
{
apply_rotation(n,coordinates,45);
apply_reflection_along_x_axis(n,coordinates);
apply_rotation(n,coordinates,-45);
}
/*************************************************************************///--------------- apply_reflection_about_line_yemx( ) -----------------///*************************************************************************/void apply_reflection_about_line_yemx(constint n,int coordinates[])
{
apply_rotation(n,coordinates,45);
apply_reflection_along_y_axis(n,coordinates);
apply_rotation(n,coordinates,-45);
}
/*************************************************************************///------------------------- apply_rotation( ) -------------------------///*************************************************************************/void apply_rotation(constint n,int coordinates[],float angle)
{
float xr=320;
float yr=240;
angle*=(M_PI/180);
for(int count_1=0;count_1<n;count_1++)
{
float matrix_a[3]={coordinates[(count_1*2)],
coordinates[((count_1*2)+1)],1};
float temp_1=(((1-cos(angle))*xr)+(yr*sin(angle)));
float temp_2=(((1-cos(angle))*yr)-(xr*sin(angle)));
float matrix_b[3][3]={ { cos(angle),sin(angle),0 } ,
{ -sin(angle),cos(angle),0 } ,
{ temp_1,temp_2,1 } };
float matrix_c[3]={0};
multiply_matrices(matrix_a,matrix_b,matrix_c);
coordinates[(count_1*2)]=(int)(matrix_c[0]+0.5);
coordinates[((count_1*2)+1)]=(int)(matrix_c[1]+0.5);
}
}
/*************************************************************************///------------------ apply_reflection_along_x_axis( ) -----------------///*************************************************************************/void apply_reflection_along_x_axis(constint n,int coordinates[])
{
for(int count=0;count<n;count++)
{
float matrix_a[3]={coordinates[(count*2)],
coordinates[((count*2)+1)],1};
float matrix_b[3][3]={ {1,0,0} , {0,-1,0} ,{ 0,0,1} };
float matrix_c[3]={0};
multiply_matrices(matrix_a,matrix_b,matrix_c);
coordinates[(count*2)]=matrix_c[0];
coordinates[((count*2)+1)]=(480+matrix_c[1]);
}
}
/*************************************************************************///------------------ apply_reflection_along_y_axis( ) -----------------///*************************************************************************/void apply_reflection_along_y_axis(constint n,int coordinates[])
{
for(int count=0;count<n;count++)
{
float matrix_a[3]={coordinates[(count*2)],
coordinates[((count*2)+1)],1};
float matrix_b[3][3]={ {-1,0,0} , {0,1,0} ,{ 0,0,1} };
float matrix_c[3]={0};
multiply_matrices(matrix_a,matrix_b,matrix_c);
coordinates[(count*2)]=(640+matrix_c[0]);
coordinates[((count*2)+1)]=matrix_c[1];
}
}
/************************************************************************///---------------------- multiply_matrices( ) ------------------------///************************************************************************/void multiply_matrices(constfloat matrix_1[3],
constfloat matrix_2[3][3],float matrix_3[3])
{
for(int count_1=0;count_1<3;count_1++)
{
for(int count_2=0;count_2<3;count_2++)
matrix_3[count_1]+=
(matrix_1[count_2]*matrix_2[count_2][count_1]);
}
}
/*************************************************************************///----------------------------- Polygon( ) ----------------------------///*************************************************************************/void Polygon(constint n,constint coordinates[])
{
if(n>=2)
{
Line(coordinates[0],coordinates[1],
coordinates[2],coordinates[3]);
for(int count=1;count<(n-1);count++)
Line(coordinates[(count*2)],coordinates[((count*2)+1)],
coordinates[((count+1)*2)],
coordinates[(((count+1)*2)+1)]);
}
}
/*************************************************************************///------------------------------- Line( ) -----------------------------///*************************************************************************/void Line(constint x_1,constint y_1,constint x_2,constint y_2)
{
int color=getcolor( );
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int inc_dec=((y2>=y1)?1:-1);
if(dx>dy)
{
int two_dy=(2*dy);
int two_dy_dx=(2*(dy-dx));
int p=((2*dy)-dx);
int x=x1;
int y=y1;
putpixel(x,y,color);
while(x<x2)
{
x++;
if(p<0)
p+=two_dy;
else
{
y+=inc_dec;
p+=two_dy_dx;
}
putpixel(x,y,color);
}
}
else
{
int two_dx=(2*dx);
int two_dx_dy=(2*(dx-dy));
int p=((2*dx)-dy);
int x=x1;
int y=y1;
putpixel(x,y,color);
while(y!=y2)
{
y+=inc_dec;
if(p<0)
p+=two_dx;
else
{
x++;
p+=two_dx_dy;
}
putpixel(x,y,color);
}
}
}
/*************************************************************************///--------------------------- Dashed_line( ) --------------------------///*************************************************************************/void Dashed_line(constint x_1,constint y_1,constint x_2,
constint y_2,constint line_type)
{
int count=0;
int color=getcolor( );
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int inc_dec=((y2>=y1)?1:-1);
if(dx>dy)
{
int two_dy=(2*dy);
int two_dy_dx=(2*(dy-dx));
int p=((2*dy)-dx);
int x=x1;
int y=y1;
putpixel(x,y,color);
while(x<x2)
{
x++;
if(p<0)
p+=two_dy;
else
{
y+=inc_dec;
p+=two_dy_dx;
}
if((count%2)!=0 && line_type==0)
putpixel(x,y,color);
elseif((count%5)!=4 && line_type==1)
putpixel(x,y,color);
elseif((count%10)!=8 && (count%10)!=9 && line_type==2)
putpixel(x,y,color);
elseif((count%20)!=18 && (count%20)!=19 && line_type==3)
putpixel(x,y,color);
elseif((count%12)!=7 && (count%12)!=8 &&
(count%12)!=10 && (count%12)!=11 && line_type==4)
putpixel(x,y,color);
count++;
}
}
else
{
int two_dx=(2*dx);
int two_dx_dy=(2*(dx-dy));
int p=((2*dx)-dy);
int x=x1;
int y=y1;
putpixel(x,y,color);
while(y!=y2)
{
y+=inc_dec;
if(p<0)
p+=two_dx;
else
{
x++;
p+=two_dx_dy;
}
if((count%2)!=0 && line_type==0)
putpixel(x,y,color);
elseif((count%5)!=4 && line_type==1)
putpixel(x,y,color);
elseif((count%10)!=8 && (count%10)!=9 && line_type==2)
putpixel(x,y,color);
elseif((count%20)!=18 && (count%20)!=19 && line_type==3)
putpixel(x,y,color);
elseif((count%12)!=7 && (count%12)!=8 &&
(count%12)!=10 && (count%12)!=11 && line_type==4)
putpixel(x,y,color);
count++;
}
}
}
/*************************************************************************///-------------------------- show_screen( ) ---------------------------///*************************************************************************/void show_screen( )
{
setfillstyle(1,1);
bar(208,26,430,38);
settextstyle(0,0,1);
setcolor(15);
outtextxy(5,5,"******************************************************************************");
outtextxy(5,17,"*-**************************************************************************-*");
outtextxy(5,29,"*----------------------- -----------------------*");
outtextxy(5,41,"*-**************************************************************************-*");
outtextxy(5,53,"*-**************************************************************************-*");
setcolor(11);
outtextxy(218,29,"Reflection Transformation");
setcolor(15);
for(int count=0;count<=30;count++)
outtextxy(5,(65+(count*12)),"*-* *-*");
outtextxy(5,438,"*-**************************************************************************-*");
outtextxy(5,450,"*------------------------- -------------------------*");
outtextxy(5,462,"******************************************************************************");
setcolor(12);
outtextxy(229,450,"Press any Key to exit.");
}