According to the nature of projectivescale, it has solved the problem of drawing a cars perspective when perspective vanishing point is out of the drafting board.
文中利用射影几何中射线比的特殊性质，解决了透视灭点在图板外的透视图画法。
2
Then, we first use the impulsive control approach to control the scaling factor of projective synchronization onto any desired scale.