In Shapes and Forms Feng Shui, scanning the environment is important.
A simple example is that there can be a threat from reflective glass commonly found in high rise buildings. Such reflective glass - firstly from the reflection of the sun, may divert light or `glare' into another building.
An example is shown here. The blue tinted reflective glare of this building known as Wisma Alsagoff reflects and many such buildings are typical examples.
In addition, this building towers over another building shown on the right of the picture.
In Hong Kong, a noticeable example is the Bank of China building. It has both pointed edges and reflective glass covering the entire building.
In many instances such buildings utilise `self-defence' e.g. protective tinted glass facade and poison arrows in the form of either sharp corners, acute angles, triangles or a combination of both.

In this paranomic photo, you can see, at a distance, a profile of some of the towers of Suntec City, Singapore.
This mega Shopping centre, office space and exhibition/convention hall uses, a smooth skin of reflective tinted glass covering it's skin. Considered as a defensive `posture'.
To find out more about past postings of pictures of Suntec City, try to do a SEARCH for it under this forum.