绘制立方体时，OpenGL表现异常奇怪

Question

当我使用这段代码绘制一个立方体时，它会这样显示：

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
gluLookAt(
x,    y,    z, 
x+xp, y+yp, z+zp,
0.0f, 1.0f, 0.0f);   
glBegin(GL_QUADS);            

glColor3f(0.0f,1.0f,0.0f);            
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);        

glColor3f(1.0f,0.5,0.0f);           
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);        

glColor3f(1.0f,0.0f,0.0f);            
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);        

glColor3f(1.0f,1.0f,0.0f);            
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);        

glColor3f(0.0f,0.0f,1.0f);            
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);        

glColor3f(1.0f,0.0f,1.0f);            
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();

我看到了一个奇怪的立方体图形： 还有 即使没有gluLookAt()函数，我仍然会得到奇怪的图形。

奇怪的是，我在一个Python OpenGL项目中使用了完全相同的代码，并没有遇到任何问题。所以这似乎是C的错误？

同时，似乎前两个四边形（绿色和橙色）根本没有被绘制。

- WIll Cobb

---

通过在我的代码中添加以下内容： glEnable(GL_DEPTH_TEST); 我解决了自己的问题。 - WIll Cobb

我想这么做，但我需要更多的声望才能实现。 - WIll Cobb

Answer 1

我通过添加以下内容解决了自己的问题：

glEnable(GL_DEPTH_TEST); 

到我的代码。

- WIll Cobb