15~

 #include <stdio.h>

#include <GL/glut.h>

float a=0;

float angle[20]={90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleOld[20]={0,90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleNew[20]={90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

void display()

{

     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

     glPushMatrix();

        glRotatef(angle[0],0,0,1);

        glutSolidTeapot(0.3);

     glPopMatrix();

     glPushMatrix();

        glTranslatef(0.5,0,0);

        glRotatef(angle[1],0,0,1);

        glutSolidTeapot(0.3);

       glPopMatrix(); 

     glPopMatrix();   

     glutSwapBuffers();

}

void readNext()

{

a+=0.1;

for(int i=0;i<20;i++) angle[i] = angleOld[i] * (1-a) + angleNew[i] * a;

printf("next\n");

}

void timer(int t){

glutTimerFunc(10, timer, 0);

readNext();

glutPostRedisplay();

}

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

{

      if(key=='r'){

        readNext();

}else if(key=='p'){

glutTimerFunc(0, timer, 0);

}

glutPostRedisplay();

}

int main()

{

glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("Week15");

glutKeyboardFunc(keyboard);

glutDisplayFunc(display);

glutMainLoop();

}