INFO: Why is gray/silver in MS Paint not equal to gray/silver in E-Run [16861]

This article applies to:
E-Prime 3.0
E-Prime 2.0
E-Prime 1.x

 
Detail
Users have inquired why the RGB (red-green-blue) value of the color Gray/Silver (RGB 128-128-128), is not the same in E-Prime as in the MS Paint progam. The reason is due to how the Windows GDI (graphic device interface) components handle RGB values in 16-bit mode.
 

In 16-bit mode, RGB values are stored as a 5-6-5 or 5-5-5 pairing. Typically, to generate smooth transitions, the most significant bits of each RGB component are shifted over to create an 8-bit value when converting from 5-6-6 to 8-8-8 pairing. The Windows GDI components do not do this transition the same way and end up being one color shade away from the typical algorithm. This makes some color matching more difficult to produce.

 
The easiest way to avoid this issue is to set the display device to run in either 24/32-bit per pixel mode, which does not truncate the RGB values.

NOTE: This is not considered a bug in E-Prime as the behavior is due to the implementation of the GDI components in Windows.