Drop shadow

A simple way of drawing a drop shadow of a rectangular object is to draw a gray or black area underneath and offset from the object. In general, a drop shadow is a copy in black or gray of the object, drawn in a slightly different position. Realism may be increased by:

1. Darkening the colors of the pixels where the shadow casts instead of making them gray. This can be done with
   alpha blending
   the shadow with the area it is cast on.
2. Softening the edges of the shadow. This can be done by adding
   alpha channel
   before blending.

Inset drop shadows are a type which draws the shadows inside the element. This allows the interface element to appear as if it is sunken into the interface.

Use

Generally,