GL

#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);glColor3f(1.0, 1.0, 1.0);glPushMatrix();glutWireSphere(1.0, 20, 16);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);glutWireSphere(0.2, 10, 8);glPopMatrix();glutSwapBuffers();}void reshape(int w, int h){glViewport(0, 0, (GLsizei)w, (GLsizei)h);glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(60.0, (GLfloat)w/(GLfloat)h, 1.0, 20.0);glMatrixMode(GL_MODELVIEW);glLoadIdentity();gluLookAt(0.0, 0.0, 5.0, 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;default :break;}}int main(int argc, char **argv){glutInit(&argc, argv);glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);glutInitWindowSize(500, 500);glutInitWindowPosition(100, 100);glutCreateWindow(argv[0]);init();glutDisplayFunc(display);glutReshapeFunc(reshape);glutKeyboardFunc(keyboard);glutMainLoop();return 0;}