Simulation of Traffic signals

My mini project on simulations of traffic signals using visual c++ and Open GL.

 

Project report to view  and to download  Source code to download

IMPLEMENTATION

1. Main function

This main function is capable of handling the arguments given in the argument list at the command prompt as we have used variable ‘argc’ for total number of arguments and ‘argv’ for the array of argument list.

Main function initializes the Display Mode, Window Size and position. Then it invokes the display function within glutDisplayFunc() as the call back function.

void main(int argc, char* argv[])

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);

glutInitWindowSize(1346,728);

glutInitWindowPosition(0,0);

glutCreateWindow("Traffic signal");

            glutDisplayFunc(mydisplay);

 /*call back functions*/

glutKeyboardFunc(myKeyboard);

glutMouseFunc(myMouse);

myinit();

glutMainLoop();

}

2. Keyboard function

This Interactive function is invoked at the main program within glutKeyboardFunc() and it is repeatedly called during the execution of the program and hence handles the keyboard interrupts from the users.

When a key is been pressed the ASCII code of the key and the position of the screen pointer at the time of interruption will be sent to the function.

void myKeyboard( unsigned char key, int x, int y )

{

switch(key)

{

     case 13:

                 if(flag==1)

                 {

                             flag=2;

                             mydisplay();

                 }

                 if(flag==0) //Ascii of 'enter' key is 13

                 {

                             flag=1;

mydisplay();

} break;

     case 'l': control_keyl=key;

                 p=0;q=0;r=1;break;

     case 'r': control_keyr=key;

                 p=0;q=0;r=1;break;

     case 's': mydisplay();break;

     case 'h': flag=1;mydisplay(); break;

     default: break;

}

}

3. Mouse function

This Interactive function is invoked at the main program within glutMoseFunc() and it is repeatedly called during the execution of the program and hence handles the Mouse interrupts from the users.

When a button is been pressed the identity of the button and the state of the button and the position of the screen pointer at the time of interruption will be sent to the mouse function.

void myMouse(int button,int state,int x,int y)

{

     if(button==GLUT_LEFT_BUTTON && state==GLUT_DOWN)

     {

     traffic_regulator=0;

     p=1;q=0;r=0;}

   if(button==GLUT_RIGHT_BUTTON && state==GLUT_DOWN)

     {

     traffic_regulator=0;

     p=0;q=1;r=0;

     }

     if(button==GLUT_RIGHT_BUTTON && state==GLUT_UP)

     {         

     traffic_regulator=1;

     p=0;q=0;r=1;

     }

     glutPostRedisplay();

}

4. Displaying text on the screen

The setFont() function is used to set the type of the font we are using. The drawstring() function takes the position of the string to be displayed on the screen in X Y Z coordinates and the string to display.

void *currentfont;

void setFont(void *font)

{

            currentfont=font;

}

void drawstring(float x,float y,float z,char *string)

{

            char *c;

            glRasterPos3f(x,y,z);

            for(c=string;*c!='\0';c++)

            {          glColor3f(0.0,0.0,0.0);

                        glutBitmapCharacter(currentfont,*c);

            }

}

void frontscreen(void)

{

setFont(GLUT_BITMAP_TIMES_ROMAN_24);

glClearColor(0.15,0.1,0.01,0);/*background for cover page*/

glClear(GL_COLOR_BUFFER_BIT);

glColor3f(1,0,0);

drawstring(450.0,700.0,0.0,"BEARYS INSTITUTE OF TECHNOLOGY ");

glFLush();

}

5. Display functions

We have used three display functions in this program the first one that is the myDisplay function is called in the main program using glutDisplayFunc() call back function. The mydisplay function controls the displaying of the front screen, help screen or the display function.

The second display function that is display() calls the objects like road(),car() etc. According to the order that we have written hence it indirectly handles the depth information.

void mydisplay(void)

{

glClear(GL_COLOR_BUFFER_BIT);

if(flag==0)

frontscreen ();

if(flag==1)

            helpscreen();

if(flag==2)

display();

glutSwapBuffers();

}

glutPostRedisplay();

}

void display(void)

{

if(traffic_regulator)

glutTimerFunc(50,update,0);

glClear(GL_COLOR_BUFFER_BIT);

glClearColor(red,green,blue,0);/*back ground for sky*/

road();

bus();

signal();

car();

car2();

glFlush();

}

6. Update functions



Update function is used for the transformation of the objects this function is invoked in display function inside glutTimerFunc(50,update,0). This function calls the update every 50 mille seconds hence the variable ‘a’, ’b’ are all modified then when we translate the object with this points we will see the animation effect.

void update(int value)

{

a=a-6;

b=b+6;

control();

/*making day to night*/

if(blue!=0&&green!=0)

{

blue-=.004;green-=.004;

}