[Android] WindowManager & Display Area

Rough Block Diagram
[Display Device] <>--- [Logical Display] <>--- [WindowManager]

DisplayInfo
has followings (Initial values are set as information from display device).
:logicalHeight
:logicalWidth
:appWidth
:appHeight

DisplayDevice
has followings
:mCurrentLayerStackRect
:mCurrentDisplayRect

                                   shown on the display.
                                           |
                                           v
[LayerStackRect] ---(project to)---> [DisplayRect]
        ^
        |
   This value is outbound of WindowManager.

Above information is very rough and... NOT strictly verified.

Here is useful tool supported by Google to handle displaying area and density - wm.
You can find it at '/system/bin/wm'

root@generic:/system/bin # ./wm reset
usage: wm [subcommand] [options]
       wm size [reset|WxH]
       wm density [reset|DENSITY]
       wm overscan [reset|LEFT,TOP,RIGHT,BOTTOM]

Very useful isn't it!