Animation

The Code

Exercises

 

 

The Code

//Press y for orbit, press d to rotate about axis

 

#include "stdafx.h"

#include <GL/glut.h>

 

static int year = 0, day = 0;

 

void init(void)

{

   glClearColor(0.0, 0.0, 0.0, 0.0);

   glShadeModel (GL_FLAT);

}

 

void display(void)

{

   glClear (GL_COLOR_BUFFER_BIT);

 

   glPushMatrix();

 

   glRotatef ((GLfloat) year, 0.0, 1.0, 0.0);

   glTranslatef (2.0, 0.0, 0.0);

   glRotatef ((GLfloat) day, 0.0, 1.0, 0.0);

   glColor4f (1.0, 0.0, 0.0, 1.0);

 

   glutSolidSphere(0.2, 10, 8);    /* draw smaller planet */

 

   glPopMatrix();

   glutSwapBuffers();

}

 

void reshape (int w, int h)

{

   glViewport (0, 0, (GLsizei) w, (GLsizei) h);

   glMatrixMode (GL_PROJECTION);

   glLoadIdentity ();

   glFrustum (-1.0, 1.0, -1.0, 1.0, 1.5, 20.0);

   glMatrixMode(GL_MODELVIEW);

   glLoadIdentity();

   gluLookAt (0.0, 0.0, 4.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

}

 

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

{

 

   switch (key)

   {

      case 'd':

         day = (day + 10) % 360;

         glutPostRedisplay();

         break;

      case 'D':

         day = (day - 10) % 360;

         glutPostRedisplay();

         break;

      case 'y':

         year = (year + 5) % 360;

         glutPostRedisplay();

         break;

      case 'Y':

         year = (year - 5) % 360;

         glutPostRedisplay();

         break;

      case 27:

         exit(0);

         break;

      default:

         break;

   }

 

}

 

int main(int argc, char** argv)

{

   glutInit(&argc, argv);

   glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);

   glutInitWindowSize (500, 500);

   glutInitWindowPosition (100, 100);

   glutCreateWindow ("Animation" );

   init ();

   glutDisplayFunc(display);

   glutReshapeFunc(reshape);

   glutKeyboardFunc(keyboard);

   glutMainLoop();

   return 0;

}