PPT: Light-Colored Text Disappears with 16-Color Video Drivers
  
PSS ID Number: Q101091
Article last modified on 05-16-1998
 
windows:2.0,2.0e,3.0,4.0
 
WINDOWS
 

======================================================================
------------------------------------------------------------------
The information in this article applies to:
 
 - Microsoft PowerPoint for Windows, versions 2.x, 3.x, and 4.0
----------------------------------------------------------------------
 
SUMMARY
=======
 
If you format text in one of the lighter colors in the Genigraphics
color palette in PowerPoint (YW7 or BG6 for example), text may appear
as white when displayed using a 16-color display driver. This causes
text to disappear when displayed in front of a white background.
 
16-color video drivers cannot dither text color. As a result, if you
have text set to a color that is not one of the 16 "pure" VGA colors,
the text appears on screen as the closest "pure" color to the one you
have chosen. Because the closest color to your selected light color is
white, the text color remaps to white and is no longer visible.
 
MORE INFORMATION
================
 
Dithering is a technique used in computer graphics to create the illusion
of varying shades of gray (on a monochrome display or printer) or
additional colors (on a color display or printer). Dithering relies on
treating areas of an image as groups of dots that are colored in different
patterns. Dithering takes advantage of the eye's tendency to blur
spots of different colors by averaging their effects and merging them into
a single perceived shade or color. (This definition was obtained from
the Microsoft Press "Computer Dictionary.")
 
If you format text to be the same color as the background, whether
intentionally or due to the video's limited capability, you won't be
able to see it. The standard VGA video driver cannot dither text so
text colors get remapped to the closest match in the driver's palette.
 
Additional query words: 2.00 2.00e 2.00x 3.00 mix color colour
winppt vanish invisible can't see cannot can not characters letters not
macppt visible ppt30 ppt40
======================================================================
Keywords          : kbdisplay kbgraphic
Version           : windows:2.0,2.0e,3.0,4.0
Platform          : WINDOWS
Hardware          : x86
Issue type        : kbprb
=============================================================================
Copyright Microsoft Corporation 1998.