Carro con movimiento

#include
GLfloat anguloCuboX = 0.0f;
GLfloat anguloCuboY = 0.0f;
GLfloat anguloEsfera = 0.0f;
GLfloat TrasPisox=0.0f;
GLfloat TrasPisoy=0.0f;
GLfloat TrasPisoz=-5.0f;

GLfloat TrasRueda1x=3.0f;
GLfloat TrasRueda1y=0.5f;
GLfloat TrasRueda1z=-1.0f;

GLfloat TrasRueda2x=-0.5f;
GLfloat TrasRueda2y=0.5f;
GLfloat TrasRueda2z=-1.0f;

GLfloat TrasCarrox=0.0f;
GLfloat TrasCarroy=0.0f;
GLfloat TrasCarroz=-5.0f;

GLfloat e;
GLint ancho=400;
GLint alto=400;
int hazPerspectiva = 0;
void reshape(int width, int height)
{
    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    if(hazPerspectiva)
               gluPerspective(60.0f, (GLfloat)width/(GLfloat)height, 1.0f, 20.0f);
     else
       glOrtho(-4,4, -4, 4, 1, 10);
       glMatrixMode(GL_MODELVIEW);
    ancho = width;
    alto = height;
}
void Piso(void)
{
    glColor3f(0.0f, 0.0f, 1.0f);
    glScalef(1.5f,0.0f,1.5f);
    glBegin(GL_QUADS);       //cara abajo
    glVertex3f( 1.0f,-1.0f, -1.0f);
    glVertex3f( 1.0f,-1.0f,  1.0f);
    glVertex3f(-1.0f,-1.0f,  1.0f);
    glVertex3f(-1.0f,-1.0f, -1.0f);
    glEnd();
}
void carro(void)
{
    glColor3f(1.0f, 0.0f, 1.0f);

    glBegin(GL_POLYGON);       //carro
    glVertex3f(-1.5f,0.5f, -2.0f);
    glVertex3f( 3.5f,0.5f, -2.0f);
    glVertex3f(3.5f,2.0f,  -2.0f);
    glVertex3f(2.0f,2.0f, -2.0f);
    glVertex3f(1.f,3.0f, -2.0f);
    glVertex3f(-0.5f,3.0f, -2.0f);
    glVertex3f(-1.5f,2.0f, -2.0f);
    glEnd();
}
void display()
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
glTranslatef(TrasPisox,TrasPisoy,TrasPisoz);
    glRotatef(15, 1.0f, 0.0f, 0.0f);
    glRotatef(15, 0.0f, 1.0f, 0.0f);
    // dibuja piso
    Piso();
 
// dibuja rueda
    glLoadIdentity();
    glTranslatef(TrasRueda1x,TrasRueda1y,TrasRueda1z);
    glColor3f(1.0f, 1.0f, 1.0f);
    glutSolidSphere(0.5f, 16, 16);
 
//dibuja 2da rueda
    glLoadIdentity();
    glTranslatef(TrasRueda2x,TrasRueda2y,TrasRueda2z);
    glColor3f(1.0f, 1.0f, 1.0f);
    glutSolidSphere(0.5f, 16, 16);


    glLoadIdentity();
    glTranslatef(TrasCarrox,TrasCarroy,TrasCarroz);
    glColor3f(1.0f, 1.0f, 1.0f);
    carro();
    glFlush();
    glutSwapBuffers();
}
void init()
{
    glClearColor(0,0,0,0);
    glEnable(GL_DEPTH_TEST);
    ancho = 400;
    alto = 400;
}
void idle()
{
    display();
}


void keyboard(unsigned char key, int x, int y)
{
    switch(key)
    {
    case 'p':
    case 'P':
 hazPerspectiva=1;
 reshape(ancho,alto);
 break;
    case 'o':
    case 'O':
 hazPerspectiva=0;
 reshape(ancho,alto);
 break;
    case 'i':
    case 'I':

   TrasRueda1x-=.10;
   TrasRueda2x-=.10;
   TrasCarrox-=.10;

 break;

case 'd':
    case 'D':
    TrasRueda1x+=.10;
TrasRueda2x+=.10;
    TrasCarrox+=.10;

      break;
    }
}



int main(int argc, char **argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
    glutInitWindowPosition(100, 100);
    glutInitWindowSize(ancho, alto);
    glutCreateWindow("Carrito");
    init();
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutIdleFunc(idle);
    glutKeyboardFunc(keyboard);
    glutMainLoop();
    return 0;
}