(GRAPHICS) * A C++ Program to illustrate the implementation of 3D Rotation Transformation along x-axis.

Code:

/*************************************************************************/
/*************************************************************************

A C++ program to illustrate the implementation of 3D Rotation Transformation
along x-axis.

*************************************************************************/
/*************************************************************************/

/*************************************************************************

*************************************************************************/

/*************************************************************************/
/*************************************************************************/
//--------------------------- Header Files ----------------------------//
/*************************************************************************/
/*************************************************************************/
# include <iostream.h>
# include <graphics.h>
# include <conio.h>
# include <math.h>
/*************************************************************************/
/*************************************************************************/
//----------------------- Global Declarations -------------------------//
/*************************************************************************/
/*************************************************************************/

# define f 0.3
# define projection_angle 45

/*************************************************************************/
/*************************************************************************/
//----------------------- Function Prototypes -------------------------//
/*************************************************************************/
/*************************************************************************/

void show_screen( );

void apply_rotation_along_x_axis(const int [5][3],const int);
void multiply_matrices(const float[4],const float[4][4],float[4]);

void draw_pyramid(int [5][3]);
void get_projected_point(int&,int&,int&);

void Line(const int,const int,const int,const int);

/*************************************************************************/
/*************************************************************************/
//------------------------------ main( ) ------------------------------//
/*************************************************************************/
/*************************************************************************/

int main( )
{
int driver=DETECT,mode;

initgraph(&driver,&mode,"c:\\tc\\Bgi");

show_screen( );

int pyramid[5][3]={
{280,130,50}, // base front left
{360,130,50}, // base front right
{360,130,-50}, // base back right
{280,130,-50}, // base back left
{320,20,0} // top
};

setcolor(15);
draw_pyramid(pyramid);

setcolor(15);
settextstyle(0,0,1);
outtextxy(50,415,"*** Use + & - Keys to apply Rotation along x-axis.");

int angle=0;
int key_code=0;

char Key=NULL;

do
{
Key=NULL;
key_code=0;

Key=getch( );
key_code=int(Key);

if(key_code==0)
{
Key=getch( );
key_code=int(Key);
}

if(key_code==27)
break;

else if(key_code==43)
angle-=5;

else if(key_code==45)
angle+=5;

setfillstyle(1,0);
bar(40,70,600,410);

apply_rotation_along_x_axis(pyramid,angle);
}
while(1);

return 0;
}

/*************************************************************************/
/*************************************************************************/
//------------------------ Funcion Definitions ------------------------//
/*************************************************************************/
/*************************************************************************/

/*************************************************************************/
//------------------- apply_rotation_along_x_axis( ) ------------------//
/*************************************************************************/

void apply_rotation_along_x_axis(const int control_points[5][3],
const int theta)
{
int edge_points[5][3]={0};

float angle=(theta*(M_PI/180));

for(int count=0;count<5;count++)
{
edge_points[count][0]=control_points[count][0];
edge_points[count][1]=control_points[count][1];
edge_points[count][2]=control_points[count][2];

float matrix_a[4]={edge_points[count][0],edge_points[count][1],
edge_points[count][2],1};
float matrix_b[4][4]={
{ 1,0,0,0 } ,
{ 0,cos(angle),sin(angle),0 } ,
{ 0,-sin(angle),cos(angle),0 } ,
{ 0,0,0,1 }
};
float matrix_c[4]={0};

multiply_matrices(matrix_a,matrix_b,matrix_c);

edge_points[count][0]=(int)(matrix_c[0]+0.5);
edge_points[count][1]=(int)(matrix_c[1]+0.5);
edge_points[count][2]=(int)(matrix_c[2]+0.5);
}

setcolor(10);
draw_pyramid(edge_points);
}

/************************************************************************/
//---------------------- multiply_matrices( ) ------------------------//
/************************************************************************/

void multiply_matrices(const float matrix_1[4],
const float matrix_2[4][4],float matrix_3[4])
{
for(int count_1=0;count_1<4;count_1++)
{
for(int count_2=0;count_2<4;count_2++)
matrix_3[count_1]+=
(matrix_1[count_2]*matrix_2[count_2][count_1]);
}
}

/************************************************************************/
//-------------------------- draw_pyramid( ) -------------------------//
/************************************************************************/

void draw_pyramid(int points[5][3])
{
int edge_points[5][3];

for(int i=0;i<5;i++)
{
edge_points[i][0]=points[i][0];
edge_points[i][1]=points[i][1];
edge_points[i][2]=points[i][2];

get_projected_point(edge_points[i][0],
edge_points[i][1],edge_points[i][2]);

edge_points[i][1]+=240;
}

Line(edge_points[0][0],edge_points[0][1],
edge_points[1][0],edge_points[1][1]);
Line(edge_points[1][0],edge_points[1][1],
edge_points[2][0],edge_points[2][1]);
Line(edge_points[2][0],edge_points[2][1],
edge_points[3][0],edge_points[3][1]);
Line(edge_points[3][0],edge_points[3][1],
edge_points[0][0],edge_points[0][1]);

Line(edge_points[0][0],edge_points[0][1],
edge_points[4][0],edge_points[4][1]);
Line(edge_points[1][0],edge_points[1][1],
edge_points[4][0],edge_points[4][1]);
Line(edge_points[2][0],edge_points[2][1],
edge_points[4][0],edge_points[4][1]);
Line(edge_points[3][0],edge_points[3][1],
edge_points[4][0],edge_points[4][1]);
}

/************************************************************************/
//--------------------- get_projected_point( ) -----------------------//
/************************************************************************/

void get_projected_point(int& x,int& y,int& z)
{
float fcos0=(f*cos(projection_angle*(M_PI/180)));
float fsin0=(f*sin(projection_angle*(M_PI/180)));

float Par_v[4][4]={
{1,0,0,0},
{0,1,0,0},
{fcos0,fsin0,0,0},
{0,0,0,1}
};

float xy[4]={x,y,z,1};
float new_xy[4]={0};

multiply_matrices(xy,Par_v,new_xy);

x=(int)(new_xy[0]+0.5);
y=(int)(new_xy[1]+0.5);
z=(int)(new_xy[2]+0.5);
}

/*************************************************************************/
//------------------------------- Line( ) -----------------------------//
/*************************************************************************/

void Line(const int x_1,const int y_1,const int x_2,const int 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
{
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);
}
}
}

/*************************************************************************/
//-------------------------- show_screen( ) ---------------------------//
/*************************************************************************/

void show_screen( )
{
setfillstyle(1,1);
bar(210,26,420,38);

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,"3D Rotation along X-axis");

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.");
}

/*************************************************************************/
/*************************************************************************/
//----------------------------- THE END -------------------------------//
/*************************************************************************/
/*************************************************************************/

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i am trying to use the dosbox in my windows7 but i could not run the files in .c

Make sure you have included directories required for the program in correct folder.
If you are confused with the dosbox installation then follow the following configuration.

Make a new folder inside the drive C: Let C:\dos.
Inside the dos folder, Put TC (Turbo C++) Files.
Now install, DosBox and Open it.
Since the execution key for turbo c++ is configured as quit key for the dos box, you have to reconfigure the keymap.
For this, Press CNTRL+F1, the keymapper will open.
Clcik on 'shutdown' on the dosbox window, and then click on 'Del'.
Finally click on 'save'.
Now you are ready to use dosbox on windows 7 and windows vista.

You have to mount the virtual drive before use.

Open DosBox, type 'mount c c:\dos' without quotes.
Now type 'c:'.
then type 'cd tc\bin'.
and open tc typing 'tc.exe'.
Enjoy compiling your hand codes.

_________________
START POSTING YOUR IDEAS AND THOUGHTS AND BUILD THE COMMUNITY OF EXPERTS.

thanks ...

malai yo kura man paryo