projek OpenGL Membuat Jam 2D beserta Sourcode dengan pemrograman C++ dan C

     Example Projek OpenGL ini membuat animasi jam yang mengikuti waktu indonesia. dilengkapi dengan sourcodenya yang dapat dicopy paste ke editor openGLnya  sehingga dapat dilihat hasilnya seperti apa. adapun hasil dari projek ini adalah seperti gambar dibawah ini.

gambar diatas merupakan objek 2 dimensi yang dibuat dengan openGL berupa animasi jam dinding yang terintegrasi waktu secara real. adapun langkah-langkahnya dapat dilihat dibawah ini.
hal yang pertama yang harus dilakukan adalah sebagai berikut :
1. install codeblock terlebih dahulu di laptop atau komputer
2. setting codeblok dengan Glut
3. copy semua sourcode dibawah ini secara lengkap supaya dapat dijalankan

berikut ini adalah sourcode yang dapat kamu coba di editor tersebut.

#include  <GL/glut.h>

#include  <string.h>

#include  <stdio.h>

#include  <stdlib.h>

#include  <math.h>

#include  <time.h>

// define glu objects
int about_int=0;
GLUquadricObj *Cylinder;
GLUquadricObj *Disk;
struct tm *newtime;
time_t ltime;
int M_TWOPI=0;
GLfloat rx, ry, rz, angle;

// lighting
GLfloat LightAmbient[]= { 0.5f, 0.5f, 0.5f, 1.0f };
GLfloat LightDiffuse[]= { 0.5f, 0.5f, 0.5f, 1.0f };
GLfloat LightPosition[]= { 5.0f, 25.0f, 15.0f, 1.0f };
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

static int light_state = 1; // light on = 1, light off = 0
static int view_state = 1; // Ortho view = 1, Perspective = 0

void Sprint( float x, float y, char *st)
{
 int l,i;
 l=strlen( st );
 glRasterPos3f( x, y, -1);
 for( i=0; i < l; i++)
  {
  glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, st[i]);
 }
}

static void TimeEvent(int te)
{
 rx = 30 * cos( angle );
 ry = 30 * sin( angle );
 rz = 30 * cos( angle );
 angle += 0.01;
 if (angle > M_TWOPI) angle = 0;
 glutPostRedisplay();
 glutTimerFunc( 100, TimeEvent, 1);
}

void init(void)
{
   glClearColor (0.0, 0.0, 0.0, 0.0);
   glShadeModel (GL_SMOOTH);
   glEnable(GL_DEPTH_TEST);
   // Lighting is added to scene

   glLightfv(GL_LIGHT1 ,GL_AMBIENT, LightAmbient);
   glLightfv(GL_LIGHT1 ,GL_DIFFUSE, LightDiffuse);
   glLightfv(GL_LIGHT1 ,GL_POSITION, LightPosition);
   glEnable(GL_LIGHTING);
   glEnable(GL_LIGHT1);


   Cylinder = gluNewQuadric();
   gluQuadricDrawStyle( Cylinder, GLU_FILL);
   gluQuadricNormals( Cylinder, GLU_SMOOTH);
   gluQuadricOrientation( Cylinder, GLU_OUTSIDE);
   gluQuadricTexture( Cylinder, GL_TRUE);


   Disk = gluNewQuadric();
   gluQuadricDrawStyle( Disk, GLU_FILL);
   gluQuadricNormals( Disk, GLU_SMOOTH);
   gluQuadricOrientation( Disk, GLU_OUTSIDE);
   gluQuadricTexture( Disk, GL_TRUE);
}



void Draw_gear( void )
{
 int i;
 glPushMatrix();
 gluCylinder(Cylinder, 2.5, 2.5, 1, 16, 16);
 gluDisk(Disk, 0, 2.5, 32, 16);
 glTranslatef(0,0,1);
    gluDisk(Disk, 0, 2.5, 32, 16);
 glPopMatrix();
    for( i = 0; i < 8; i++)
  {
     glPushMatrix();
  glTranslatef( 0.0, 0.0, 0.50);
  glRotatef( (360/8) * i, 0.0, 0.0, 1.0);
  glTranslatef( 3.0, 0.0, 0.0);
  glutSolidCube( 1.0 );
  glPopMatrix();
     }
}

void Draw_clock( GLfloat cx, GLfloat cy, GLfloat cz )
{
  int hour_ticks , sec_ticks;
  glPushMatrix();
  glTranslatef(cx,cy,cz);
  glRotatef( 180, 1.0, 0.0, 0.0);

  /*glPushMatrix(); // Draw large wire cube (outside of disk clock)
  glColor3f(1.0, 1.0, 1.0);
  glTranslatef( 0.0, 0.0, 6.0);
  glutWireCube(14.0);
  glPopMatrix();*/


  glPushMatrix(); // Draw clock face
  glTranslatef( 0, 0, 1.0);
  gluDisk(Disk, 0, 6.75, 32, 16);
  glPopMatrix();

  glPushMatrix();// Draw hour hand
  glColor3f(1.0, 0.5, 0.5);
  glTranslatef( 0, 0, 0.0);
  glRotatef( (360/12) * newtime->tm_hour  + (360/60) * (60 / (newtime->tm_min+1)), 0.0, 0.0, 1.0);

  glPushMatrix();
  glTranslatef(0.0, 0.0, 2.0);
  Draw_gear();
  glPopMatrix();
  glRotatef( 90, 1.0, 0.0, 0.0);
  gluCylinder(Cylinder, 0.75, 0, 4, 16, 16);
  glPopMatrix();
  glPushMatrix();// Draw minute hand
  glColor3f(1.0, 0.5, 1.0);
  glTranslatef( 0, 0, 0.0);
  glRotatef( (360/60) * newtime->tm_min, 0.0, 0.0, 1.0);
  glPushMatrix();
  glTranslatef(0.0, 0.0, 3.0);
  glScalef(0.5, 0.5, 1.0);

  Draw_gear();
  glPopMatrix();
  glRotatef( 90, 1.0, 0.0, 0.0);
  gluCylinder(Cylinder, 0.5, 0, 6, 16, 16);
  glPopMatrix();

  glPushMatrix();// Draw second hand
  glColor3f(1.0, 0.0, 0.5);
  glTranslatef( 0, 0, -0.0);
  glRotatef( (360/60) * newtime->tm_sec, 0.0, 0.0, 1.0);
  glPushMatrix();
  glTranslatef(0.0, 0.0, 4.0);
  glScalef(0.25, 0.25, 1.0);

  Draw_gear();
  glPopMatrix();
  glRotatef( 90, 1.0, 0.0, 0.0);
  gluCylinder(Cylinder, 0.25, 0, 6, 16, 16);
  glPopMatrix();

  for(hour_ticks = 0; hour_ticks < 12; hour_ticks++)
   {
   glPushMatrix();// Draw next arm axis.
      glColor3f(0.0, 1.0, 1.0); // give it a color
   glTranslatef(0.0, 0.0, 0.0);
   glRotatef( (360/12) * hour_ticks, 0.0, 0.0, 1.0);
      glTranslatef( 6.0, 0.0, 0.0);
   glutSolidCube(1.0);
      glPopMatrix();

  }


  for(sec_ticks = 0; sec_ticks < 60; sec_ticks++)
  {
    glPushMatrix();
 glTranslatef(0.0, 0.0, 0.0);
 glRotatef( (360/60) * sec_ticks, 0.0, 0.0, 1.0);
 glTranslatef(6.0, 0.0, 0.0);
 glutSolidCube(0.25);
 glPopMatrix();
 }

  glPopMatrix();
}

void num()
{
    if(view_state == 1)
 {
 glColor3f( 0.0, 0.0, 1.0);
 Sprint(-6.2,-0.2,"9"); //counting from center
 Sprint(-0.2,-6.2,"6");
 Sprint(-0.4,5.7,"12");
 Sprint(5.8,-0.2,"3");
 }
}



void about()
{

    //glClear(GL_COLOR_BUFFER_BIT);

 glColor3f( 1.0, 1.0, 1.0);
    Sprint(-5,-2,"This project implements the clock");
 Sprint(-5,-2.8,"   Both Wall clock and digit clock");
 Sprint(-5,-3.6,"               is displayed");
    Sprint(-5,-4.4,"   Clock shows the local time");
 Sprint(-5,-5.2,"    fetching from computer");
 //glFlush();
}



void display_clock()
{
 time(&ltime); // Get time
  newtime = localtime(&ltime); // Convert to local time
  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  // easy way to put text on the screen.
  glMatrixMode (GL_PROJECTION);
  glLoadIdentity();
  glOrtho(-8.0, 8.0, -8.0, 8.0, 1.0, 60.0);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glDisable(GL_LIGHTING);
  glDisable(GL_COLOR_MATERIAL);



  // Put view state on screen
  glColor3f( 1.0, 1.0, 1.0);
  if (view_state == 0 && about_int==0)
   {
   Sprint(-3, -4, "Perspective view");
   }
  else if (view_state != 0 && about_int==0)
  {
   Sprint(-2, -4, "Ortho view");
  }
  else
  {
   about();
  }

      Sprint(-4,-7.7, asctime(newtime));
  // Turn Perspective mode on/off
  if (view_state == 0)
     {
     glMatrixMode (GL_PROJECTION);
     glLoadIdentity();
     gluPerspective(60.0, 1, 1.0, 60.0);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
     gluLookAt( rx, 0.0, rz, 0.0, 0.0, -14.0, 0, 1, 0);
  }



 if (light_state == 1)
   {
    glEnable(GL_LIGHTING);
    glEnable(GL_COLOR_MATERIAL);  // Enable for lighing
      }else
   {
   glDisable(GL_LIGHTING);
   glDisable(GL_COLOR_MATERIAL);  // Disable for no lighing
  }
Draw_clock( 0.0, 0.0, -14.0);
num();
glutSwapBuffers();
}





void display(void)
{
  glClear(GL_COLOR_BUFFER_BIT);
  display_clock();
  glFlush();
}



void reshape (int w, int h)

{

   glViewport (0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();

}


void options(int id)
{
 switch(id)
 {

  case 1:
   glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
 about_int= abs(about_int - 1);
   break;

  case 2:
   glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
   view_state = abs(view_state - 1);
   break;

  case 3:
   glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    light_state = abs(light_state - 1);
      break;

  case 4 :
   exit(0);

 }

 }



int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
   glutInitWindowSize (500, 500);
   glutInitWindowPosition (50, 50);
   glutCreateWindow (argv[0]);
   glutSetWindowTitle("GLclock");
   init ();
   glutCreateMenu(options);
   glutAddMenuEntry("About the Project",1);
   glutAddMenuEntry("Toggle Ortho/Perspective view",2);
   glutAddMenuEntry("Light on/off",3);
   glutAddMenuEntry("Quit",4);
   glutAttachMenu(GLUT_RIGHT_BUTTON);
   glutDisplayFunc(display);
   glutReshapeFunc(reshape);
   glutTimerFunc( 10, TimeEvent, 1);
   glutMainLoop();
   return 0;
}

kemudian hasil dari kode diatas adalah seperti dibawah ini yang nantinya jam akan bergerak mengikuti waktu secara real dan akurat.

semoga apa yang saya tulis bermanfaat untuk yang lainnya sehingga dapat menyelesaikan tugas komputer grafiknya yang menggunakan openGL.

1. http://www.openglprojects.in/2012/04/mini-project-on-clock-using-opengl.html#gsc.tab=0