I want to draw a cube with the following code, and I find the procedure A work well , the procedure B doesn't. I can't find any problem, if anyone find the problem with Procedure B, please tell me.
Code :
GLfloat vertex_listss[][3] = {
  -0.5f, -0.5f, -0.5f,
  0.5f, -0.5f, -0.5f, 
  -0.5f,  0.5f, -0.5f, 
  0.5f,  0.5f, -0.5f, 
 
  -0.5f, -0.5f,  0.5f, 
  0.5f, -0.5f,  0.5f, 
  -0.5f,  0.5f,  0.5f, 
  0.5f,  0.5f,  0.5f,
};
 
GLfloat normalize[][3] = {
  0, 0, -1.0f,
 0, 0, -1.0f,
 0, 0, -1.0f,
 0, 0, -1.0f,
 
  -1.0f, 0, 0,
 -1.0f, 0, 0,
 -1.0f, 0, 0,
 -1.0f, 0, 0,
 
   0, -1.0f,  0,
   0, -1.0f,  0,
   0, -1.0f,  0,
   0, -1.0f,  0,
 
   0, 0, 1.0f,
   0, 0, 1.0f,
   0, 0, 1.0f,
   0, 0, 1.0f,
 
   1.0f, 0, 0,
   1.0f, 0, 0,
   1.0f, 0, 0,
   1.0f, 0, 0,
 
   0, 1.0f, 0,
   0, 1.0f, 0,
   0, 1.0f, 0,
   0, 1.0f, 0,
};
 
// the index of the vertexs
static const GLint index_list[] = {
  0, 2, 3, 1, 
  0, 4, 6, 2,
  0, 1, 5, 4,
  4, 5, 7, 6,
  1, 3, 7, 5,
  2, 6, 7, 3,
};
 
void cubedraw(){
#if 0 // Procedure A
  for(int i = 0 ; i < sizeof(index_list)/sizeof(index_list[0]); i += 4) {
    glBegin(GL_QUADS);
    glNormal3f(normalize[i][0],normalize[i][1],normalize[i][2]);
    for(int j = i; j < i + 4; j ++) {
      int index = index_list[j];
      glVertex3f(vertex_listss[index][0], 
        vertex_listss[index][1], 
        vertex_listss[index][2]);
    }
    glEnd();
  }
#else //  Procedure B
  glEnableClientState(GL_NORMAL_ARRAY);
  glNormalPointer(GL_FLOAT, 0, normalize);
 
    glEnableClientState(GL_VERTEX_ARRAY);
  glVertexPointer(3, GL_FLOAT, 0, vertex_listss);
 
 
  glDrawElements(GL_QUADS,
    sizeof(index_list)/sizeof(index_list[0]), 
    GL_UNSIGNED_INT, index_list);
 
#endif
};