opengl中如何实现视点的实时跟踪

Question

我画了一个机器人，并模拟其飞行，飞行过程中图像发生了变形，我对其视点进行了变换可是达不到我想要的效果，哪位帮我看看，不胜感激。
void CRobotView::drawrobot()
{

glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
gluLookAt(m_xView,m_yView,m_zView,m_xView,m_yView,-10.0,0.0,1.0,0.0); //在这里设置视点变化，m_xView代表视点此时的位置，

robot();  //绘制飞机
glFlush();
}void CRobotView::robot()        //绘制飞机
{
//绘制一个椭圆代表机身
glPushMatrix();
glTranslatef(m_xPos,m_yPos,m_zPos); //实现飞机的运动
    
glPushMatrix();
glScalef(1.0,0.5,1.0);
glutSolidSphere(3.0,100,100);
glPopMatrix(); //绘制三个脚
glPushMatrix();
glTranslatef(0.0,-2.0,2.0);
glRotatef(40.0,1.0,0.0,0.0);
auxSolidBox(0.4,0.2,4.0);
glTranslatef(0.0,0.0,2.0);
glutSolidSphere(0.3,20,30);
glPopMatrix(); glPushMatrix();
glRotatef(120.0,0.0,1.0,0.0);
    glTranslatef(0.0,-2.0,3.5);
glRotatef(40.0,1.0,0.0,0.0);
auxSolidBox(0.4,0.2,4.0);
glTranslatef(0.0,0.0,2.0);
glutSolidSphere(0.3,20,30);
glPopMatrix();  glPushMatrix();
glRotatef(240.0,0.0,1.0,0.0);
    glTranslatef(0.0,-2.0,3.5);
glRotatef(40.0,1.0,0.0,0.0);
auxSolidBox(0.4,0.2,4.0);
glTranslatef(0.0,0.0,2.0);
glutSolidSphere(0.3,20,30);
glPopMatrix();    //绘制脖颈 
glPushMatrix();

glTranslatef(0.0,1.3,0.0);
auxSolidCylinder(0.35,0.8);
glTranslatef(0.0,1.1,0.0);
glutSolidSphere(0.45,20,20);
//绘制机翼
glPushMatrix();
glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(35.0+rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPushMatrix();
glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(155.0+rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPushMatrix();
glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(250.0+rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPopMatrix();   //绘制脖颈
      glPushMatrix();

glTranslatef(0.0,2.5,0.0);
auxSolidCylinder(0.35,0.8);
glTranslatef(0.0,1.1,0.0);
glutSolidSphere(0.45,20,20);
//绘制机翼
glPushMatrix();
        glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(-35.0-rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPushMatrix();
        glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(-155.0-rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPushMatrix();
         glRotatef(-90.0,0.0,0.0,1.0);
glRotatef(-275.0-rotate,1.0,0.0,0.0);
glTranslatef(0.0,2.6,0.0);
auxSolidCylinder(0.1,4.0);
glPopMatrix();

glPopMatrix();
glPopMatrix();    
}
void CRobotView::OnTimer(UINT nIDEvent) 
{
// TODO: Add your message handler code here and/or call defaultif(nIDEvent==1)
{
if(v<2000.0&&m_xPos==0.0)        //起飞前机翼的旋转过程，加速旋转
{
t+=1;
v=v+a*t;
rotate=v;
}
else
{
if(m_xPos==0.0&&m_yPos<5.0)            //起飞过程，飞机匀速上升
{
m_yPos=m_yPos+0.1;
rotate=rotate+v;
m_yView=m_yPos;           //我想使视点移动的距离与飞机                                          移动的距离相等。


} 
else
{
if(m_yPos>=5.0&&m_xPos<8.0)  //飞翔过程，飞机水平方向上 匀速加一，视点的位置也跟着加一。
{
    m_xPos=m_xPos+0.1;
    rotate=rotate+v;
    m_xView=m_xPos;
}
else
{
if(m_xPos>=8.0&&m_yPos>0.0)            //飞机降落过程，y轴方向上匀速减一，视点在y方向上也匀速减一。
{
m_yPos=m_yPos-0.1;
rotate=rotate+v;
                  m_yView=m_yPos
}
else
{
if(m_yPos<=0.0&&rotate>0.0)            //机翼停止旋转
{
 rotate=(int)(rotate)%360-5;
}
else        
{
        OnStop() ;
}
}
}
}
}
}  
  PostMessage(WM_PAINT);
  
  CView::OnTimer(nIDEvent);
}开始时m_xView,m_yView,m_zView,m_xPos,m_yPos,m_zPos初始值均为0。我想飞机移动了多少距离让视点跟着移动相应的距离就可以了，但是并不是我想象的那样，是不是我对矩阵变换还没有理解，希望各位高手给我一点儿建议。

Answer 1

您的意思是我这样设置对？能给我具体解释一下gluLookAt()这个函数的意义吗。我再网上查了很多都是关于它的表面解释但是真正用起来就遇到麻烦了。得到的并不是我想象的那样，视点随着飞机移动。

Answer 2

我以前写的一个（模拟开飞机的），你可以参考一下
#define KEY_DOWN(vk_code)((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
//移动镜头函数
float  rad_xz;
static float eyex=0.0,eyez=0.0,lookx=0.0,lookz=-500.0;
static float g_Angle=0.0;
BOOL DisplayScene()
{
float speed=1.2f; if (KEY_DOWN(VK_SHIFT))speed=speed*4; //按shift加速 if (KEY_DOWN('A'))   g_Angle+=speed*2; //按A左转
if (KEY_DOWN('D'))  g_Angle-=speed*2; //按D右转
rad_xz = float (3.13149* g_Angle/180.0f);
if (KEY_DOWN('W'))                    //按W前进
{
eyex-=sin(rad_xz)*speed;
eyez-=cos(rad_xz)*speed;
int i=0;
}
if (KEY_DOWN('S'))                      //按S后退
{
eyex+=sin(rad_xz)*speed;
eyez+=cos(rad_xz)*speed;
}

lookx=eyex-1000*sin(rad_xz);
lookz=eyez-1000*cos(rad_xz);

gluLookAt(eyex,0.0,eyez,lookx,0.0,lookz,0.0,1.0,0.0);
return TRUE;
}

Answer 3

你可以定义一个观察的方向（用两个角度：旋转角和俯仰角），然后在Lookat函数里边设置前6个参数，使得眼睛的位置总是在目标沿着该方向固定的距离处。