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Subject: computer drawing OPENE GL GLUT .
Hello, I want your help in writing comments on the lines of this code so that it is easier for me to understand. Thank you for your cooperation with me .
#include <windows.h>#include <stdlib.h>#include <GL/glut.h>static int year1=0, day1=0, year2=0, day2=0;void init(void) { glClearColor(0.0,0.0,0.0,0.0); GLfloat mat_specular[]={1.0,1.0,1.0,1.0}; GLfloat mat_shininess[]={50.0}; GLfloat light_position0[]={1.0,1.0,1.0,0.0}; glClearColor(0.0,0.0,0.0,0.0); glShadeModel(GL_SMOOTH); glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular); glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess); glLightfv(GL_LIGHT0,GL_POSITION,light_position0); GLfloat light_position1[] = {-1.0f, 0.5f, 0.5f, 0.0f}; glLightfv(GL_LIGHT1, GL_POSITION, light_position1); glEnable(GL_COLOR_MATERIAL); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_LIGHT1); glEnable(GL_NORMALIZE); glEnable(GL_DEPTH_TEST);}void display(void) { glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); glColor3f(1.0,1.0,1.0); glPushMatrix(); glutSolidSphere(1.0,20,16); glRotatef((GLfloat)year1,0.0,1.0,0.0); glTranslatef(2.0,0.0,0.0); glRotatef((GLfloat)day1,0.0,1.0,0.0); glutSolidSphere(0.2,10,8); glPopMatrix(); glPushMatrix(); glRotatef((GLfloat)year2,0.0,1.0,1.0); glTranslatef(2.0,1.0,0.0); glRotatef((GLfloat)day2,0.0,1.0,0.0); glutSolidSphere(0.2,10,8); glPopMatrix(); glutSwapBuffers();}void reshape(int w, int h) { glViewport(0,0,(GLsizei)w,(GLsizei)h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(40.0,(GLfloat)w/(GLfloat)h,1.0,20.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); gluLookAt(0.0,0.0,8.0,0.0,0.0,0.0,0.0,1.0,0.0);}void keyboard(unsigned char key, int x, int y) { switch(key) { case 'd': day1=(day1+15)%360; glutPostRedisplay(); day2=(day2-10)%360; glutPostRedisplay(); break; case 'y': year1=(year1+10)%360; glutPostRedisplay(); year2=(year2-5)%360; glutPostRedisplay(); break; }}int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_DEPTH); glutInitWindowSize(600,600); glutInitWindowPosition(0,0); glutCreateWindow("UJIAN"); init(); glutDisplayFunc(display); glutReshapeFunc(reshape); glutKeyboardFunc(keyboard); glutMainLoop(); return 0;}
#include <windows.h>
#include <stdlib.h>
#include <GL/glut.h>
static int year1=0, day1=0, year2=0, day2=0;
void init(void) {
glClearColor(0.0,0.0,0.0,0.0);
GLfloat mat_specular[]={1.0,1.0,1.0,1.0};
GLfloat mat_shininess[]={50.0};
GLfloat light_position0[]={1.0,1.0,1.0,0.0};
glClearColor(0.0,0.0,0.0,0.0);
glShadeModel(GL_SMOOTH);
glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);
glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess);
glLightfv(GL_LIGHT0,GL_POSITION,light_position0);
GLfloat light_position1[] = {-1.0f, 0.5f, 0.5f, 0.0f};
glLightfv(GL_LIGHT1, GL_POSITION, light_position1);
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_LIGHT1);
glEnable(GL_NORMALIZE);
glEnable(GL_DEPTH_TEST);
}
void display(void) {
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glColor3f(1.0,1.0,1.0);
glPushMatrix();
glutSolidSphere(1.0,20,16);
glRotatef((GLfloat)year1,0.0,1.0,0.0);
glTranslatef(2.0,0.0,0.0);
glRotatef((GLfloat)day1,0.0,1.0,0.0);
glutSolidSphere(0.2,10,8);
glPopMatrix();
glPushMatrix();
glRotatef((GLfloat)year2,0.0,1.0,1.0);
glTranslatef(2.0,1.0,0.0);
glRotatef((GLfloat)day2,0.0,1.0,0.0);
glutSolidSphere(0.2,10,8);
glPopMatrix();
glutSwapBuffers();
}
void reshape(int w, int h) {
glViewport(0,0,(GLsizei)w,(GLsizei)h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(40.0,(GLfloat)w/(GLfloat)h,1.0,20.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0.0,0.0,8.0,0.0,0.0,0.0,0.0,1.0,0.0);
}
void keyboard(unsigned char key, int x, int y) {
switch(key) {
case 'd':
day1=(day1+15)%360; glutPostRedisplay();
day2=(day2-10)%360; glutPostRedisplay();
break;
case 'y':
year1=(year1+10)%360; glutPostRedisplay();
year2=(year2-5)%360; glutPostRedisplay();
break;
}
}
int main(int argc, char** argv) {
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_DEPTH);
glutInitWindowSize(600,600);
glutInitWindowPosition(0,0);
glutCreateWindow("UJIAN");
init();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);
glutMainLoop();
return 0;
}