在opengl中绘制同一对象的多个副本

Question

我似乎无法理解如何使用对象数组绘制同一对象的多个副本。下面你会看到我的绘图和显示方法：

void display()
{
    SolidSphere **spheres = createSpheres();
    float const win_aspect = (float)win_width / (float)win_height;

    glViewport(0, 0, win_width, win_height);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glColor3f(.6, 0, 0);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(45, win_aspect, 1, 10);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

    for (int i = 0; i < n; i++)
    {
        spheres[i]->draw(posX,posY,posZ);
    }

    glutSwapBuffers();
}

void draw(GLfloat x, GLfloat y, GLfloat z)
{
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glTranslatef(x,y,z);

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_NORMAL_ARRAY);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);

    glVertexPointer(3, GL_FLOAT, 0, &vertices[0]);
    glNormalPointer(GL_FLOAT, 0, &normals[0]);
    glTexCoordPointer(2, GL_FLOAT, 0, &texcoords[0]);
    glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_SHORT, &indices[0]);
    glPopMatrix();

    glDisableClientState(GL_VERTEX_ARRAY);
    glDisableClientState(GL_NORMAL_ARRAY);
    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
}

结果我只得到1而不是n球。