OpenGL step to step(2)

这是一个类似于地球绕太阳旋转的demo

原有的例子是用键盘接受事件，我做了修改，使用了timer把他变成一个动态旋转的

#import <Foundation/Foundation.h>
#include <GLUT/GLUT.h>
static int year=,day=;
void init()
{
    glClearColor(,,,);
    glShadeModel(GL_FLAT);
}

void display()
{
    glClear(GL_COLOR_BUFFER_BIT);
    glColor3f(,,);
    glPushMatrix();
    glutWireSphere(,,);
    glRotatef((GLfloat)year,,,);
    glTranslated(,,);

    glRotatef((GLfloat)day,,,);
    glutWireSphere(0.2,,);
    glPopMatrix();
    glutSwapBuffers();

    }

void reshape(int w,int h)
{
    glViewport(, , (GLsizei)w, (GLsizei)h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    gluPerspective(,(GLfloat)w/(GLfloat)h,,);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    gluLookAt(,,,,,,,,);
}

void fishboard()
{
    day=(day+)%;
    year=(year+)%;
    glutPostRedisplay();
}

void timerProc(int id)
{
    fishboard();
    glutTimerFunc(,timerProc,);//需要在函数中再调用一次，才能保证循环
}

int main(int argc,char **argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
    glutInitWindowSize(, );
    glutInitWindowPosition(,);
    glutCreateWindow("Xcode Glut Demo");
    init();

    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutTimerFunc(,timerProc,);

    glutMainLoop();
    return ;
}