Ideal screen rotation

[Dave Ball]

Rui Miguel Silva Seabra wrote:
> On Tue, Nov 10, 2009 at 12:00:31AM +0000, Dave Ball wrote:
>> option1: New atoms in the _NET_WM_STATE property.
>> - _NET_WM_STATE_LANDSCAPE
>> - _NET_WM_STATE_PORTRAIT
>>
>> If neither is present for a given window, WM can choose (based on
>> the accelerometers). Both present is an error - or could be defined
>> as leave the window in it's current orientation.
>>
>> option2: New property.
>>
>> _NET_WM_ORIENTATION
>> 0 = Either / WM decides
>> 1 = Landscape
>> 2 = Portrait
>
> There are two landscape positions and 2 portrait positions :)
Doh - of course!  Which would lead to:

_NET_WM_STATE_ORIENTATION_LANDSCAPE
_NET_WM_STATE_ORIENTATION_PORTRAIT
_NET_WM_STATE_ORIENTATION_INVERTED

or

_NET_WM_ORIENTATION
0 = Either / WM decides
1 = Landscape
2 = Portrait
3 = Landscape inverted
4 = Portrait inverted

However, what's the use-case for an application requesting either of the 
inverted states?  I can't see when those would be useful - in terms of 
hints the app would supply.

Obviously, if the WM was deciding orientation based on the device 
position, you would correctly rotate to the inverted states, but if an 
application is built for portrait or landscape is there any reason a 
developer would not want the "normal" portrait/landscape orientation for 
the device?


Dave