#include<windows.h>
#define GLUT_DISABLE_ATEXIT_HACK
#include <gl/glut.h>
#include <math.h>//for PI value , sine and cosine function that we used to draw lines
float PI= 3.141592654;
float angleHour = 0, angleMin = 0, angleSec = 0, clockR = 80.0f, angle1min = PI / 30.0f, minStart = 0.9f, minEnd = 1.0f, stepStart = 0.8f, stepEnd = 1.0f;
void init() {
glClearColor(0.0f, 0.5f, 1.0f, 1.0f);
glMatrixMode(GL_PROJECTION);
glOrtho(-150, 150, -100, 100, -100, 100);
}
//number method is used to write the numbers found in the clock
void numbers()
{
glRasterPos2i(58, 0);
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, '3');
glRasterPos2i(0, -60);
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, '6');
glRasterPos2i(-62, -2);
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, '9');
glRasterPos2i(-2, 57);
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, '1');
glRasterPos2i(1, 57);
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, '2');
}
//display function responsible to design the classic clock interface
void Display() {
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0f, 0.0f, 0.0f);
glLineWidth(2);
glEnable(GL_LINE_SMOOTH);//for drawing smooth lines
glBegin(GL_LINES);
for (int i = 0; i < 60; i++) {
float c = cos(i * angle1min), s = sin(i * angle1min);
if (i % 5) { // normal minute
if (i % 5 == 1)
glColor3f(1.0f, 1.0f, 1.0f);
//The following is to draw white lines around the circle
glVertex2f(clockR * minStart * c, clockR * minStart * s);
glVertex2f(clockR * minEnd * c, clockR * minEnd * s);
}
else {
glColor3f(0.0f, 1.0f, 0.0f);
//The following is to draw red long lines around the circle
glVertex2f(clockR * stepStart * c, clockR * stepStart * s);
glVertex2f(clockR * stepEnd * c, clockR * stepEnd * s);
}
}
glEnd();
numbers();
//the following is for second hand
glColor3f(0.0f, 1.0f, 0.0f);
glPushMatrix();
glTranslatef(-1, 3, 0);
glPushMatrix();
glRotatef(-angleSec, 0, 0, 1);
glPushMatrix();
glTranslatef(1, -3, 0);
glBegin(GL_LINES);
glVertex2i(-1, 3);
glVertex2i(9, -45);
glEnd();
glBegin(GL_TRIANGLES);
glVertex2i(9, -48);
glVertex2i(9, -42);
glVertex2i(9, -40);
glEnd();
glPopMatrix();
glPopMatrix();
glPopMatrix();
//for minute hand
glLineWidth(8);
glColor3f(0.0, 0.0, 1.0);
glPushMatrix();
glTranslatef(-1, 3, 0);
glPushMatrix();
glRotatef(-angleMin, 0, 0, 1);
glPushMatrix();
glTranslatef(1, -3, 0);
glBegin(GL_LINES);
glVertex2i(-1, 3);
glVertex2i(40, 2);
glEnd();
glBegin(GL_TRIANGLES);
glVertex2i(40, -3);
glVertex2i(40, 7);
glVertex2i(45, 2);
glEnd();
glPopMatrix();
glPopMatrix();
glPopMatrix();
//for hour hand
glLineWidth(10);
glColor3f(1.0f, 0.0f, 0.0f);
glPushMatrix();
glTranslatef(-1, 3, 0);
glPushMatrix();
glRotatef(-angleHour, 0, 0, 1);
glPushMatrix();
glTranslatef(1, -3, 0);
glBegin(GL_LINES);
glVertex2i(-1, 3);
glVertex2i(0, 35);
glEnd();
glBegin(GL_TRIANGLES);
glVertex2i(-5, 35);
glVertex2i(0, 40);
glVertex2i(5, 35);
glEnd();
glPopMatrix();
glPopMatrix();
glPopMatrix();
//circle design
glPushMatrix();
glTranslatef(-140, -160, 0);
float Xpos = 140, Ypos = 160, radius = 90;
glColor3f(1.0, 0.0, 0.0);
glBegin(GL_LINE_STRIP);
for (float i = 0; i < 360; i += 0.01)
glVertex2f(Xpos + sin(i) * radius, Ypos + cos(i) * radius);
glEnd();
radius = 80;
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_LINE_STRIP);
for (float i = 0; i < 360; i += 0.01)
glVertex2f(Xpos + sin(i) * radius, Ypos + cos(i) * radius);
glEnd();
radius = 85;
glColor3f(1.0, 1.0, 0.0);
glBegin(GL_LINE_STRIP);
for (float i = 0; i < 360; i += 0.01)
glVertex2f(Xpos + sin(i) * radius, Ypos + cos(i) * radius);
glEnd();
glLineWidth(15);
glPopMatrix();
glColor3f(1.0, 0.5, 0.5);
glPointSize(12);
glBegin(GL_POINTS);
glVertex2i(-1, 3);
glEnd();
glFlush();
}
//rotate function manages how the hour,minute and second
//hand are simulated
void rotate()
{
if (angleSec < 360)
{
angleSec += 0.03;
}
else
{
angleSec = 0;
}
if (angleMin < 360)
{
angleMin += 0.00085;
}
else
{
angleMin = 0;
}
if (angleHour < 360)
{
angleHour += 0.0000146;
}
else
{
angleHour = 0;
}
glutPostRedisplay();
}
int main(int argc, char* argv[]) {
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(100, 10);
glutInitWindowSize(1080, 780);
glutCreateWindow("Classic Clock Simulation");
init();
glutDisplayFunc(Display);
glutIdleFunc(rotate);
glutMainLoop();
return 0;
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