Week14

 1 timer設定

#include <GL/glut.h>

float angle=0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glRotatef(angle,0,0,1);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void timer(int t)///timer()函式,做對應動作

{

    glutTimerFunc(500,timer,t+1);///設定下一個鬧鐘

    angle+=90;///增加90度

    glutPostRedisplay();///重畫畫面

}

int main(int argc,char** argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE |GLUT_DEPTH);

    glutCreateWindow("week14");

    glutDisplayFunc(display);

    glutTimerFunc(2000,timer,0);///設定timer函式

    glutMainLoop();

}

2 進階

#include <GL/glut.h>

float angle=0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glRotatef(angle,0,0,1);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void timer(int t)///timer()函式,做對應動作

{

    glutTimerFunc(500,timer,t+1);///設定下一個鬧鐘

    angle+=90;///增加90度

    glutPostRedisplay();///重畫畫面

}

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

{

    glutTimerFunc(0,timer,0);///設定timer函式

}

int main(int argc,char** argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE |GLUT_DEPTH);

    glutCreateWindow("week14");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);///keyboard()

    glutMainLoop();

}

3.進階進階

#include <GL/glut.h>

float angle=0,oldangle=0,newangle=0; ///宣告變數

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glRotatef(angle,0,0,1);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void timer(int t)///timer()函式,做對應動作

{

    if(t<100) glutTimerFunc(50,timer,t+1);

    float alpha = t/100.0;///變成float值介於0.00~1.00之間

    angle = newangle*alpha +(1-alpha) * oldangle;

    glutPostRedisplay();///重畫畫面

}

void motion(int x,int y)

{

    angle = x;///即時更新角度

    glutPostRedisplay();///重畫畫面

}

void mouse(int button,int state,int x,int y)

{

    if(state==GLUT_DOWN) oldangle=x;///放下去

    if(state==GLUT_UP) newangle=x;///放開來

    glutPostRedisplay();///重畫畫面

}

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

{

    glutTimerFunc(0,timer,0);///設定timer函式

}

int main(int argc,char** argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE |GLUT_DEPTH);

    glutCreateWindow("week14");

    glutDisplayFunc(display);

    glutMouseFunc(mouse);///按下去表示起點

    glutMotionFunc(motion);///當mouse在motion時，即時更新畫面

    glutKeyboardFunc(keyboard);///keyboard()

    glutMainLoop();

}