projected angle

Angle comparison of two vectors in three dimensional space is converted to that of two projected vectors in two dimensional plane, then to two mapped points in one dimensional projection line.

通过将拓扑映射引入到背向面去除判断中，将三维向量的空间角度关系判断转化成二维平面上投影向量的角度判断，然后再转化成一维射影直线上映射点的位置判断。

For the downward-projected wall jets, the capacity that the jets attach to the wall is affected by the distance or the angle between the slot diffuser and the wall, and the parameter at the exit.

对于垂直向下壁面贴附射流，射流的贴附效应与送风口和壁面之间的距离、射流与壁面之间的夹角以及送风口出口参数有关。

The regional flatness and tilt angle with respect to the camera plane are calculated in order to judge whether the current region meets the projected landing area.

计算场景中区域的平坦度以及相对摄像机平面的倾角，以判断当前区域是否满足预先设定的降落区域要求。