Auto backlight management?

Bert Freudenberg bert at
Thu Apr 24 17:58:54 EDT 2008

On 24.04.2008, at 20:32, C. Scott Ananian wrote:
> ... backlight management which automatically switches the screen  
> into a
> high-resolution black-and-white mode ...

Unless I am severely confused (or the hardware was changed) there is  
no such feature.

The XO does not have an ambient light sensor. The backlight is not  
turned off automatically in sunlight. Both "modes", reflective and  
backlit, are "active" all the time (unless the backlight is turned off  
manually). It's simply that under sunlight, the b/w reflection is much  
stronger than the colored backlight, so you are not able to see colors  

There is, however, a DCON mode specifically designed for the b/w  
reflective case, the anti-aliasing can be turned off and a color-to- 
gray mixing turned on, but again, this is done manually (in the  
current UI it is coupled to turning off the backlight).

And, to dispel another myth, the frame-buffer resolution is not  
different in "b/w mode". It is 1200x900, all the time, color or not,  
and this is all that matters to software developers. The perceived  
resolution of hue gets lower due to the physical pattern of colored  
pixels, but perceived resolution of shade is as it was (modulo the  
blurring induced by the anti-aliasing).

- Bert -

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